xref: /linux/arch/x86/kvm/x86.c (revision 89a58812)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Kernel-based Virtual Machine driver for Linux
4  *
5  * derived from drivers/kvm/kvm_main.c
6  *
7  * Copyright (C) 2006 Qumranet, Inc.
8  * Copyright (C) 2008 Qumranet, Inc.
9  * Copyright IBM Corporation, 2008
10  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
11  *
12  * Authors:
13  *   Avi Kivity   <avi@qumranet.com>
14  *   Yaniv Kamay  <yaniv@qumranet.com>
15  *   Amit Shah    <amit.shah@qumranet.com>
16  *   Ben-Ami Yassour <benami@il.ibm.com>
17  */
18 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
19 
20 #include <linux/kvm_host.h>
21 #include "irq.h"
22 #include "ioapic.h"
23 #include "mmu.h"
24 #include "i8254.h"
25 #include "tss.h"
26 #include "kvm_cache_regs.h"
27 #include "kvm_emulate.h"
28 #include "mmu/page_track.h"
29 #include "x86.h"
30 #include "cpuid.h"
31 #include "pmu.h"
32 #include "hyperv.h"
33 #include "lapic.h"
34 #include "xen.h"
35 #include "smm.h"
36 
37 #include <linux/clocksource.h>
38 #include <linux/interrupt.h>
39 #include <linux/kvm.h>
40 #include <linux/fs.h>
41 #include <linux/vmalloc.h>
42 #include <linux/export.h>
43 #include <linux/moduleparam.h>
44 #include <linux/mman.h>
45 #include <linux/highmem.h>
46 #include <linux/iommu.h>
47 #include <linux/cpufreq.h>
48 #include <linux/user-return-notifier.h>
49 #include <linux/srcu.h>
50 #include <linux/slab.h>
51 #include <linux/perf_event.h>
52 #include <linux/uaccess.h>
53 #include <linux/hash.h>
54 #include <linux/pci.h>
55 #include <linux/timekeeper_internal.h>
56 #include <linux/pvclock_gtod.h>
57 #include <linux/kvm_irqfd.h>
58 #include <linux/irqbypass.h>
59 #include <linux/sched/stat.h>
60 #include <linux/sched/isolation.h>
61 #include <linux/mem_encrypt.h>
62 #include <linux/entry-kvm.h>
63 #include <linux/suspend.h>
64 #include <linux/smp.h>
65 
66 #include <trace/events/ipi.h>
67 #include <trace/events/kvm.h>
68 
69 #include <asm/debugreg.h>
70 #include <asm/msr.h>
71 #include <asm/desc.h>
72 #include <asm/mce.h>
73 #include <asm/pkru.h>
74 #include <linux/kernel_stat.h>
75 #include <asm/fpu/api.h>
76 #include <asm/fpu/xcr.h>
77 #include <asm/fpu/xstate.h>
78 #include <asm/pvclock.h>
79 #include <asm/div64.h>
80 #include <asm/irq_remapping.h>
81 #include <asm/mshyperv.h>
82 #include <asm/hypervisor.h>
83 #include <asm/tlbflush.h>
84 #include <asm/intel_pt.h>
85 #include <asm/emulate_prefix.h>
86 #include <asm/sgx.h>
87 #include <clocksource/hyperv_timer.h>
88 
89 #define CREATE_TRACE_POINTS
90 #include "trace.h"
91 
92 #define MAX_IO_MSRS 256
93 #define KVM_MAX_MCE_BANKS 32
94 
95 /*
96  * Note, kvm_caps fields should *never* have default values, all fields must be
97  * recomputed from scratch during vendor module load, e.g. to account for a
98  * vendor module being reloaded with different module parameters.
99  */
100 struct kvm_caps kvm_caps __read_mostly;
101 EXPORT_SYMBOL_GPL(kvm_caps);
102 
103 #define  ERR_PTR_USR(e)  ((void __user *)ERR_PTR(e))
104 
105 #define emul_to_vcpu(ctxt) \
106 	((struct kvm_vcpu *)(ctxt)->vcpu)
107 
108 /* EFER defaults:
109  * - enable syscall per default because its emulated by KVM
110  * - enable LME and LMA per default on 64 bit KVM
111  */
112 #ifdef CONFIG_X86_64
113 static
114 u64 __read_mostly efer_reserved_bits = ~((u64)(EFER_SCE | EFER_LME | EFER_LMA));
115 #else
116 static u64 __read_mostly efer_reserved_bits = ~((u64)EFER_SCE);
117 #endif
118 
119 static u64 __read_mostly cr4_reserved_bits = CR4_RESERVED_BITS;
120 
121 #define KVM_EXIT_HYPERCALL_VALID_MASK (1 << KVM_HC_MAP_GPA_RANGE)
122 
123 #define KVM_CAP_PMU_VALID_MASK KVM_PMU_CAP_DISABLE
124 
125 #define KVM_X2APIC_API_VALID_FLAGS (KVM_X2APIC_API_USE_32BIT_IDS | \
126                                     KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK)
127 
128 static void update_cr8_intercept(struct kvm_vcpu *vcpu);
129 static void process_nmi(struct kvm_vcpu *vcpu);
130 static void __kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags);
131 static void store_regs(struct kvm_vcpu *vcpu);
132 static int sync_regs(struct kvm_vcpu *vcpu);
133 static int kvm_vcpu_do_singlestep(struct kvm_vcpu *vcpu);
134 
135 static int __set_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2);
136 static void __get_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2);
137 
138 static DEFINE_MUTEX(vendor_module_lock);
139 struct kvm_x86_ops kvm_x86_ops __read_mostly;
140 
141 #define KVM_X86_OP(func)					     \
142 	DEFINE_STATIC_CALL_NULL(kvm_x86_##func,			     \
143 				*(((struct kvm_x86_ops *)0)->func));
144 #define KVM_X86_OP_OPTIONAL KVM_X86_OP
145 #define KVM_X86_OP_OPTIONAL_RET0 KVM_X86_OP
146 #include <asm/kvm-x86-ops.h>
147 EXPORT_STATIC_CALL_GPL(kvm_x86_get_cs_db_l_bits);
148 EXPORT_STATIC_CALL_GPL(kvm_x86_cache_reg);
149 
150 static bool __read_mostly ignore_msrs = 0;
151 module_param(ignore_msrs, bool, 0644);
152 
153 bool __read_mostly report_ignored_msrs = true;
154 module_param(report_ignored_msrs, bool, 0644);
155 EXPORT_SYMBOL_GPL(report_ignored_msrs);
156 
157 unsigned int min_timer_period_us = 200;
158 module_param(min_timer_period_us, uint, 0644);
159 
160 static bool __read_mostly kvmclock_periodic_sync = true;
161 module_param(kvmclock_periodic_sync, bool, 0444);
162 
163 /* tsc tolerance in parts per million - default to 1/2 of the NTP threshold */
164 static u32 __read_mostly tsc_tolerance_ppm = 250;
165 module_param(tsc_tolerance_ppm, uint, 0644);
166 
167 static bool __read_mostly vector_hashing = true;
168 module_param(vector_hashing, bool, 0444);
169 
170 bool __read_mostly enable_vmware_backdoor = false;
171 module_param(enable_vmware_backdoor, bool, 0444);
172 EXPORT_SYMBOL_GPL(enable_vmware_backdoor);
173 
174 /*
175  * Flags to manipulate forced emulation behavior (any non-zero value will
176  * enable forced emulation).
177  */
178 #define KVM_FEP_CLEAR_RFLAGS_RF	BIT(1)
179 static int __read_mostly force_emulation_prefix;
180 module_param(force_emulation_prefix, int, 0644);
181 
182 int __read_mostly pi_inject_timer = -1;
183 module_param(pi_inject_timer, bint, 0644);
184 
185 /* Enable/disable PMU virtualization */
186 bool __read_mostly enable_pmu = true;
187 EXPORT_SYMBOL_GPL(enable_pmu);
188 module_param(enable_pmu, bool, 0444);
189 
190 bool __read_mostly eager_page_split = true;
191 module_param(eager_page_split, bool, 0644);
192 
193 /* Enable/disable SMT_RSB bug mitigation */
194 static bool __read_mostly mitigate_smt_rsb;
195 module_param(mitigate_smt_rsb, bool, 0444);
196 
197 /*
198  * Restoring the host value for MSRs that are only consumed when running in
199  * usermode, e.g. SYSCALL MSRs and TSC_AUX, can be deferred until the CPU
200  * returns to userspace, i.e. the kernel can run with the guest's value.
201  */
202 #define KVM_MAX_NR_USER_RETURN_MSRS 16
203 
204 struct kvm_user_return_msrs {
205 	struct user_return_notifier urn;
206 	bool registered;
207 	struct kvm_user_return_msr_values {
208 		u64 host;
209 		u64 curr;
210 	} values[KVM_MAX_NR_USER_RETURN_MSRS];
211 };
212 
213 u32 __read_mostly kvm_nr_uret_msrs;
214 EXPORT_SYMBOL_GPL(kvm_nr_uret_msrs);
215 static u32 __read_mostly kvm_uret_msrs_list[KVM_MAX_NR_USER_RETURN_MSRS];
216 static struct kvm_user_return_msrs __percpu *user_return_msrs;
217 
218 #define KVM_SUPPORTED_XCR0     (XFEATURE_MASK_FP | XFEATURE_MASK_SSE \
219 				| XFEATURE_MASK_YMM | XFEATURE_MASK_BNDREGS \
220 				| XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \
221 				| XFEATURE_MASK_PKRU | XFEATURE_MASK_XTILE)
222 
223 u64 __read_mostly host_efer;
224 EXPORT_SYMBOL_GPL(host_efer);
225 
226 bool __read_mostly allow_smaller_maxphyaddr = 0;
227 EXPORT_SYMBOL_GPL(allow_smaller_maxphyaddr);
228 
229 bool __read_mostly enable_apicv = true;
230 EXPORT_SYMBOL_GPL(enable_apicv);
231 
232 u64 __read_mostly host_xss;
233 EXPORT_SYMBOL_GPL(host_xss);
234 
235 u64 __read_mostly host_arch_capabilities;
236 EXPORT_SYMBOL_GPL(host_arch_capabilities);
237 
238 const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
239 	KVM_GENERIC_VM_STATS(),
240 	STATS_DESC_COUNTER(VM, mmu_shadow_zapped),
241 	STATS_DESC_COUNTER(VM, mmu_pte_write),
242 	STATS_DESC_COUNTER(VM, mmu_pde_zapped),
243 	STATS_DESC_COUNTER(VM, mmu_flooded),
244 	STATS_DESC_COUNTER(VM, mmu_recycled),
245 	STATS_DESC_COUNTER(VM, mmu_cache_miss),
246 	STATS_DESC_ICOUNTER(VM, mmu_unsync),
247 	STATS_DESC_ICOUNTER(VM, pages_4k),
248 	STATS_DESC_ICOUNTER(VM, pages_2m),
249 	STATS_DESC_ICOUNTER(VM, pages_1g),
250 	STATS_DESC_ICOUNTER(VM, nx_lpage_splits),
251 	STATS_DESC_PCOUNTER(VM, max_mmu_rmap_size),
252 	STATS_DESC_PCOUNTER(VM, max_mmu_page_hash_collisions)
253 };
254 
255 const struct kvm_stats_header kvm_vm_stats_header = {
256 	.name_size = KVM_STATS_NAME_SIZE,
257 	.num_desc = ARRAY_SIZE(kvm_vm_stats_desc),
258 	.id_offset = sizeof(struct kvm_stats_header),
259 	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
260 	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
261 		       sizeof(kvm_vm_stats_desc),
262 };
263 
264 const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
265 	KVM_GENERIC_VCPU_STATS(),
266 	STATS_DESC_COUNTER(VCPU, pf_taken),
267 	STATS_DESC_COUNTER(VCPU, pf_fixed),
268 	STATS_DESC_COUNTER(VCPU, pf_emulate),
269 	STATS_DESC_COUNTER(VCPU, pf_spurious),
270 	STATS_DESC_COUNTER(VCPU, pf_fast),
271 	STATS_DESC_COUNTER(VCPU, pf_mmio_spte_created),
272 	STATS_DESC_COUNTER(VCPU, pf_guest),
273 	STATS_DESC_COUNTER(VCPU, tlb_flush),
274 	STATS_DESC_COUNTER(VCPU, invlpg),
275 	STATS_DESC_COUNTER(VCPU, exits),
276 	STATS_DESC_COUNTER(VCPU, io_exits),
277 	STATS_DESC_COUNTER(VCPU, mmio_exits),
278 	STATS_DESC_COUNTER(VCPU, signal_exits),
279 	STATS_DESC_COUNTER(VCPU, irq_window_exits),
280 	STATS_DESC_COUNTER(VCPU, nmi_window_exits),
281 	STATS_DESC_COUNTER(VCPU, l1d_flush),
282 	STATS_DESC_COUNTER(VCPU, halt_exits),
283 	STATS_DESC_COUNTER(VCPU, request_irq_exits),
284 	STATS_DESC_COUNTER(VCPU, irq_exits),
285 	STATS_DESC_COUNTER(VCPU, host_state_reload),
286 	STATS_DESC_COUNTER(VCPU, fpu_reload),
287 	STATS_DESC_COUNTER(VCPU, insn_emulation),
288 	STATS_DESC_COUNTER(VCPU, insn_emulation_fail),
289 	STATS_DESC_COUNTER(VCPU, hypercalls),
290 	STATS_DESC_COUNTER(VCPU, irq_injections),
291 	STATS_DESC_COUNTER(VCPU, nmi_injections),
292 	STATS_DESC_COUNTER(VCPU, req_event),
293 	STATS_DESC_COUNTER(VCPU, nested_run),
294 	STATS_DESC_COUNTER(VCPU, directed_yield_attempted),
295 	STATS_DESC_COUNTER(VCPU, directed_yield_successful),
296 	STATS_DESC_COUNTER(VCPU, preemption_reported),
297 	STATS_DESC_COUNTER(VCPU, preemption_other),
298 	STATS_DESC_IBOOLEAN(VCPU, guest_mode),
299 	STATS_DESC_COUNTER(VCPU, notify_window_exits),
300 };
301 
302 const struct kvm_stats_header kvm_vcpu_stats_header = {
303 	.name_size = KVM_STATS_NAME_SIZE,
304 	.num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
305 	.id_offset = sizeof(struct kvm_stats_header),
306 	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
307 	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
308 		       sizeof(kvm_vcpu_stats_desc),
309 };
310 
311 u64 __read_mostly host_xcr0;
312 
313 static struct kmem_cache *x86_emulator_cache;
314 
315 /*
316  * When called, it means the previous get/set msr reached an invalid msr.
317  * Return true if we want to ignore/silent this failed msr access.
318  */
kvm_msr_ignored_check(u32 msr,u64 data,bool write)319 static bool kvm_msr_ignored_check(u32 msr, u64 data, bool write)
320 {
321 	const char *op = write ? "wrmsr" : "rdmsr";
322 
323 	if (ignore_msrs) {
324 		if (report_ignored_msrs)
325 			kvm_pr_unimpl("ignored %s: 0x%x data 0x%llx\n",
326 				      op, msr, data);
327 		/* Mask the error */
328 		return true;
329 	} else {
330 		kvm_debug_ratelimited("unhandled %s: 0x%x data 0x%llx\n",
331 				      op, msr, data);
332 		return false;
333 	}
334 }
335 
kvm_alloc_emulator_cache(void)336 static struct kmem_cache *kvm_alloc_emulator_cache(void)
337 {
338 	unsigned int useroffset = offsetof(struct x86_emulate_ctxt, src);
339 	unsigned int size = sizeof(struct x86_emulate_ctxt);
340 
341 	return kmem_cache_create_usercopy("x86_emulator", size,
342 					  __alignof__(struct x86_emulate_ctxt),
343 					  SLAB_ACCOUNT, useroffset,
344 					  size - useroffset, NULL);
345 }
346 
347 static int emulator_fix_hypercall(struct x86_emulate_ctxt *ctxt);
348 
kvm_async_pf_hash_reset(struct kvm_vcpu * vcpu)349 static inline void kvm_async_pf_hash_reset(struct kvm_vcpu *vcpu)
350 {
351 	int i;
352 	for (i = 0; i < ASYNC_PF_PER_VCPU; i++)
353 		vcpu->arch.apf.gfns[i] = ~0;
354 }
355 
kvm_on_user_return(struct user_return_notifier * urn)356 static void kvm_on_user_return(struct user_return_notifier *urn)
357 {
358 	unsigned slot;
359 	struct kvm_user_return_msrs *msrs
360 		= container_of(urn, struct kvm_user_return_msrs, urn);
361 	struct kvm_user_return_msr_values *values;
362 	unsigned long flags;
363 
364 	/*
365 	 * Disabling irqs at this point since the following code could be
366 	 * interrupted and executed through kvm_arch_hardware_disable()
367 	 */
368 	local_irq_save(flags);
369 	if (msrs->registered) {
370 		msrs->registered = false;
371 		user_return_notifier_unregister(urn);
372 	}
373 	local_irq_restore(flags);
374 	for (slot = 0; slot < kvm_nr_uret_msrs; ++slot) {
375 		values = &msrs->values[slot];
376 		if (values->host != values->curr) {
377 			wrmsrl(kvm_uret_msrs_list[slot], values->host);
378 			values->curr = values->host;
379 		}
380 	}
381 }
382 
kvm_probe_user_return_msr(u32 msr)383 static int kvm_probe_user_return_msr(u32 msr)
384 {
385 	u64 val;
386 	int ret;
387 
388 	preempt_disable();
389 	ret = rdmsrl_safe(msr, &val);
390 	if (ret)
391 		goto out;
392 	ret = wrmsrl_safe(msr, val);
393 out:
394 	preempt_enable();
395 	return ret;
396 }
397 
kvm_add_user_return_msr(u32 msr)398 int kvm_add_user_return_msr(u32 msr)
399 {
400 	BUG_ON(kvm_nr_uret_msrs >= KVM_MAX_NR_USER_RETURN_MSRS);
401 
402 	if (kvm_probe_user_return_msr(msr))
403 		return -1;
404 
405 	kvm_uret_msrs_list[kvm_nr_uret_msrs] = msr;
406 	return kvm_nr_uret_msrs++;
407 }
408 EXPORT_SYMBOL_GPL(kvm_add_user_return_msr);
409 
kvm_find_user_return_msr(u32 msr)410 int kvm_find_user_return_msr(u32 msr)
411 {
412 	int i;
413 
414 	for (i = 0; i < kvm_nr_uret_msrs; ++i) {
415 		if (kvm_uret_msrs_list[i] == msr)
416 			return i;
417 	}
418 	return -1;
419 }
420 EXPORT_SYMBOL_GPL(kvm_find_user_return_msr);
421 
kvm_user_return_msr_cpu_online(void)422 static void kvm_user_return_msr_cpu_online(void)
423 {
424 	unsigned int cpu = smp_processor_id();
425 	struct kvm_user_return_msrs *msrs = per_cpu_ptr(user_return_msrs, cpu);
426 	u64 value;
427 	int i;
428 
429 	for (i = 0; i < kvm_nr_uret_msrs; ++i) {
430 		rdmsrl_safe(kvm_uret_msrs_list[i], &value);
431 		msrs->values[i].host = value;
432 		msrs->values[i].curr = value;
433 	}
434 }
435 
kvm_set_user_return_msr(unsigned slot,u64 value,u64 mask)436 int kvm_set_user_return_msr(unsigned slot, u64 value, u64 mask)
437 {
438 	unsigned int cpu = smp_processor_id();
439 	struct kvm_user_return_msrs *msrs = per_cpu_ptr(user_return_msrs, cpu);
440 	int err;
441 
442 	value = (value & mask) | (msrs->values[slot].host & ~mask);
443 	if (value == msrs->values[slot].curr)
444 		return 0;
445 	err = wrmsrl_safe(kvm_uret_msrs_list[slot], value);
446 	if (err)
447 		return 1;
448 
449 	msrs->values[slot].curr = value;
450 	if (!msrs->registered) {
451 		msrs->urn.on_user_return = kvm_on_user_return;
452 		user_return_notifier_register(&msrs->urn);
453 		msrs->registered = true;
454 	}
455 	return 0;
456 }
457 EXPORT_SYMBOL_GPL(kvm_set_user_return_msr);
458 
drop_user_return_notifiers(void)459 static void drop_user_return_notifiers(void)
460 {
461 	unsigned int cpu = smp_processor_id();
462 	struct kvm_user_return_msrs *msrs = per_cpu_ptr(user_return_msrs, cpu);
463 
464 	if (msrs->registered)
465 		kvm_on_user_return(&msrs->urn);
466 }
467 
kvm_get_apic_base(struct kvm_vcpu * vcpu)468 u64 kvm_get_apic_base(struct kvm_vcpu *vcpu)
469 {
470 	return vcpu->arch.apic_base;
471 }
472 
kvm_get_apic_mode(struct kvm_vcpu * vcpu)473 enum lapic_mode kvm_get_apic_mode(struct kvm_vcpu *vcpu)
474 {
475 	return kvm_apic_mode(kvm_get_apic_base(vcpu));
476 }
477 EXPORT_SYMBOL_GPL(kvm_get_apic_mode);
478 
kvm_set_apic_base(struct kvm_vcpu * vcpu,struct msr_data * msr_info)479 int kvm_set_apic_base(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
480 {
481 	enum lapic_mode old_mode = kvm_get_apic_mode(vcpu);
482 	enum lapic_mode new_mode = kvm_apic_mode(msr_info->data);
483 	u64 reserved_bits = kvm_vcpu_reserved_gpa_bits_raw(vcpu) | 0x2ff |
484 		(guest_cpuid_has(vcpu, X86_FEATURE_X2APIC) ? 0 : X2APIC_ENABLE);
485 
486 	if ((msr_info->data & reserved_bits) != 0 || new_mode == LAPIC_MODE_INVALID)
487 		return 1;
488 	if (!msr_info->host_initiated) {
489 		if (old_mode == LAPIC_MODE_X2APIC && new_mode == LAPIC_MODE_XAPIC)
490 			return 1;
491 		if (old_mode == LAPIC_MODE_DISABLED && new_mode == LAPIC_MODE_X2APIC)
492 			return 1;
493 	}
494 
495 	kvm_lapic_set_base(vcpu, msr_info->data);
496 	kvm_recalculate_apic_map(vcpu->kvm);
497 	return 0;
498 }
499 
500 /*
501  * Handle a fault on a hardware virtualization (VMX or SVM) instruction.
502  *
503  * Hardware virtualization extension instructions may fault if a reboot turns
504  * off virtualization while processes are running.  Usually after catching the
505  * fault we just panic; during reboot instead the instruction is ignored.
506  */
kvm_spurious_fault(void)507 noinstr void kvm_spurious_fault(void)
508 {
509 	/* Fault while not rebooting.  We want the trace. */
510 	BUG_ON(!kvm_rebooting);
511 }
512 EXPORT_SYMBOL_GPL(kvm_spurious_fault);
513 
514 #define EXCPT_BENIGN		0
515 #define EXCPT_CONTRIBUTORY	1
516 #define EXCPT_PF		2
517 
exception_class(int vector)518 static int exception_class(int vector)
519 {
520 	switch (vector) {
521 	case PF_VECTOR:
522 		return EXCPT_PF;
523 	case DE_VECTOR:
524 	case TS_VECTOR:
525 	case NP_VECTOR:
526 	case SS_VECTOR:
527 	case GP_VECTOR:
528 		return EXCPT_CONTRIBUTORY;
529 	default:
530 		break;
531 	}
532 	return EXCPT_BENIGN;
533 }
534 
535 #define EXCPT_FAULT		0
536 #define EXCPT_TRAP		1
537 #define EXCPT_ABORT		2
538 #define EXCPT_INTERRUPT		3
539 #define EXCPT_DB		4
540 
exception_type(int vector)541 static int exception_type(int vector)
542 {
543 	unsigned int mask;
544 
545 	if (WARN_ON(vector > 31 || vector == NMI_VECTOR))
546 		return EXCPT_INTERRUPT;
547 
548 	mask = 1 << vector;
549 
550 	/*
551 	 * #DBs can be trap-like or fault-like, the caller must check other CPU
552 	 * state, e.g. DR6, to determine whether a #DB is a trap or fault.
553 	 */
554 	if (mask & (1 << DB_VECTOR))
555 		return EXCPT_DB;
556 
557 	if (mask & ((1 << BP_VECTOR) | (1 << OF_VECTOR)))
558 		return EXCPT_TRAP;
559 
560 	if (mask & ((1 << DF_VECTOR) | (1 << MC_VECTOR)))
561 		return EXCPT_ABORT;
562 
563 	/* Reserved exceptions will result in fault */
564 	return EXCPT_FAULT;
565 }
566 
kvm_deliver_exception_payload(struct kvm_vcpu * vcpu,struct kvm_queued_exception * ex)567 void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu,
568 				   struct kvm_queued_exception *ex)
569 {
570 	if (!ex->has_payload)
571 		return;
572 
573 	switch (ex->vector) {
574 	case DB_VECTOR:
575 		/*
576 		 * "Certain debug exceptions may clear bit 0-3.  The
577 		 * remaining contents of the DR6 register are never
578 		 * cleared by the processor".
579 		 */
580 		vcpu->arch.dr6 &= ~DR_TRAP_BITS;
581 		/*
582 		 * In order to reflect the #DB exception payload in guest
583 		 * dr6, three components need to be considered: active low
584 		 * bit, FIXED_1 bits and active high bits (e.g. DR6_BD,
585 		 * DR6_BS and DR6_BT)
586 		 * DR6_ACTIVE_LOW contains the FIXED_1 and active low bits.
587 		 * In the target guest dr6:
588 		 * FIXED_1 bits should always be set.
589 		 * Active low bits should be cleared if 1-setting in payload.
590 		 * Active high bits should be set if 1-setting in payload.
591 		 *
592 		 * Note, the payload is compatible with the pending debug
593 		 * exceptions/exit qualification under VMX, that active_low bits
594 		 * are active high in payload.
595 		 * So they need to be flipped for DR6.
596 		 */
597 		vcpu->arch.dr6 |= DR6_ACTIVE_LOW;
598 		vcpu->arch.dr6 |= ex->payload;
599 		vcpu->arch.dr6 ^= ex->payload & DR6_ACTIVE_LOW;
600 
601 		/*
602 		 * The #DB payload is defined as compatible with the 'pending
603 		 * debug exceptions' field under VMX, not DR6. While bit 12 is
604 		 * defined in the 'pending debug exceptions' field (enabled
605 		 * breakpoint), it is reserved and must be zero in DR6.
606 		 */
607 		vcpu->arch.dr6 &= ~BIT(12);
608 		break;
609 	case PF_VECTOR:
610 		vcpu->arch.cr2 = ex->payload;
611 		break;
612 	}
613 
614 	ex->has_payload = false;
615 	ex->payload = 0;
616 }
617 EXPORT_SYMBOL_GPL(kvm_deliver_exception_payload);
618 
kvm_queue_exception_vmexit(struct kvm_vcpu * vcpu,unsigned int vector,bool has_error_code,u32 error_code,bool has_payload,unsigned long payload)619 static void kvm_queue_exception_vmexit(struct kvm_vcpu *vcpu, unsigned int vector,
620 				       bool has_error_code, u32 error_code,
621 				       bool has_payload, unsigned long payload)
622 {
623 	struct kvm_queued_exception *ex = &vcpu->arch.exception_vmexit;
624 
625 	ex->vector = vector;
626 	ex->injected = false;
627 	ex->pending = true;
628 	ex->has_error_code = has_error_code;
629 	ex->error_code = error_code;
630 	ex->has_payload = has_payload;
631 	ex->payload = payload;
632 }
633 
634 /* Forcibly leave the nested mode in cases like a vCPU reset */
kvm_leave_nested(struct kvm_vcpu * vcpu)635 static void kvm_leave_nested(struct kvm_vcpu *vcpu)
636 {
637 	kvm_x86_ops.nested_ops->leave_nested(vcpu);
638 }
639 
kvm_multiple_exception(struct kvm_vcpu * vcpu,unsigned nr,bool has_error,u32 error_code,bool has_payload,unsigned long payload,bool reinject)640 static void kvm_multiple_exception(struct kvm_vcpu *vcpu,
641 		unsigned nr, bool has_error, u32 error_code,
642 	        bool has_payload, unsigned long payload, bool reinject)
643 {
644 	u32 prev_nr;
645 	int class1, class2;
646 
647 	kvm_make_request(KVM_REQ_EVENT, vcpu);
648 
649 	/*
650 	 * If the exception is destined for L2 and isn't being reinjected,
651 	 * morph it to a VM-Exit if L1 wants to intercept the exception.  A
652 	 * previously injected exception is not checked because it was checked
653 	 * when it was original queued, and re-checking is incorrect if _L1_
654 	 * injected the exception, in which case it's exempt from interception.
655 	 */
656 	if (!reinject && is_guest_mode(vcpu) &&
657 	    kvm_x86_ops.nested_ops->is_exception_vmexit(vcpu, nr, error_code)) {
658 		kvm_queue_exception_vmexit(vcpu, nr, has_error, error_code,
659 					   has_payload, payload);
660 		return;
661 	}
662 
663 	if (!vcpu->arch.exception.pending && !vcpu->arch.exception.injected) {
664 	queue:
665 		if (reinject) {
666 			/*
667 			 * On VM-Entry, an exception can be pending if and only
668 			 * if event injection was blocked by nested_run_pending.
669 			 * In that case, however, vcpu_enter_guest() requests an
670 			 * immediate exit, and the guest shouldn't proceed far
671 			 * enough to need reinjection.
672 			 */
673 			WARN_ON_ONCE(kvm_is_exception_pending(vcpu));
674 			vcpu->arch.exception.injected = true;
675 			if (WARN_ON_ONCE(has_payload)) {
676 				/*
677 				 * A reinjected event has already
678 				 * delivered its payload.
679 				 */
680 				has_payload = false;
681 				payload = 0;
682 			}
683 		} else {
684 			vcpu->arch.exception.pending = true;
685 			vcpu->arch.exception.injected = false;
686 		}
687 		vcpu->arch.exception.has_error_code = has_error;
688 		vcpu->arch.exception.vector = nr;
689 		vcpu->arch.exception.error_code = error_code;
690 		vcpu->arch.exception.has_payload = has_payload;
691 		vcpu->arch.exception.payload = payload;
692 		if (!is_guest_mode(vcpu))
693 			kvm_deliver_exception_payload(vcpu,
694 						      &vcpu->arch.exception);
695 		return;
696 	}
697 
698 	/* to check exception */
699 	prev_nr = vcpu->arch.exception.vector;
700 	if (prev_nr == DF_VECTOR) {
701 		/* triple fault -> shutdown */
702 		kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
703 		return;
704 	}
705 	class1 = exception_class(prev_nr);
706 	class2 = exception_class(nr);
707 	if ((class1 == EXCPT_CONTRIBUTORY && class2 == EXCPT_CONTRIBUTORY) ||
708 	    (class1 == EXCPT_PF && class2 != EXCPT_BENIGN)) {
709 		/*
710 		 * Synthesize #DF.  Clear the previously injected or pending
711 		 * exception so as not to incorrectly trigger shutdown.
712 		 */
713 		vcpu->arch.exception.injected = false;
714 		vcpu->arch.exception.pending = false;
715 
716 		kvm_queue_exception_e(vcpu, DF_VECTOR, 0);
717 	} else {
718 		/* replace previous exception with a new one in a hope
719 		   that instruction re-execution will regenerate lost
720 		   exception */
721 		goto queue;
722 	}
723 }
724 
kvm_queue_exception(struct kvm_vcpu * vcpu,unsigned nr)725 void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr)
726 {
727 	kvm_multiple_exception(vcpu, nr, false, 0, false, 0, false);
728 }
729 EXPORT_SYMBOL_GPL(kvm_queue_exception);
730 
kvm_requeue_exception(struct kvm_vcpu * vcpu,unsigned nr)731 void kvm_requeue_exception(struct kvm_vcpu *vcpu, unsigned nr)
732 {
733 	kvm_multiple_exception(vcpu, nr, false, 0, false, 0, true);
734 }
735 EXPORT_SYMBOL_GPL(kvm_requeue_exception);
736 
kvm_queue_exception_p(struct kvm_vcpu * vcpu,unsigned nr,unsigned long payload)737 void kvm_queue_exception_p(struct kvm_vcpu *vcpu, unsigned nr,
738 			   unsigned long payload)
739 {
740 	kvm_multiple_exception(vcpu, nr, false, 0, true, payload, false);
741 }
742 EXPORT_SYMBOL_GPL(kvm_queue_exception_p);
743 
kvm_queue_exception_e_p(struct kvm_vcpu * vcpu,unsigned nr,u32 error_code,unsigned long payload)744 static void kvm_queue_exception_e_p(struct kvm_vcpu *vcpu, unsigned nr,
745 				    u32 error_code, unsigned long payload)
746 {
747 	kvm_multiple_exception(vcpu, nr, true, error_code,
748 			       true, payload, false);
749 }
750 
kvm_complete_insn_gp(struct kvm_vcpu * vcpu,int err)751 int kvm_complete_insn_gp(struct kvm_vcpu *vcpu, int err)
752 {
753 	if (err)
754 		kvm_inject_gp(vcpu, 0);
755 	else
756 		return kvm_skip_emulated_instruction(vcpu);
757 
758 	return 1;
759 }
760 EXPORT_SYMBOL_GPL(kvm_complete_insn_gp);
761 
complete_emulated_insn_gp(struct kvm_vcpu * vcpu,int err)762 static int complete_emulated_insn_gp(struct kvm_vcpu *vcpu, int err)
763 {
764 	if (err) {
765 		kvm_inject_gp(vcpu, 0);
766 		return 1;
767 	}
768 
769 	return kvm_emulate_instruction(vcpu, EMULTYPE_NO_DECODE | EMULTYPE_SKIP |
770 				       EMULTYPE_COMPLETE_USER_EXIT);
771 }
772 
kvm_inject_page_fault(struct kvm_vcpu * vcpu,struct x86_exception * fault)773 void kvm_inject_page_fault(struct kvm_vcpu *vcpu, struct x86_exception *fault)
774 {
775 	++vcpu->stat.pf_guest;
776 
777 	/*
778 	 * Async #PF in L2 is always forwarded to L1 as a VM-Exit regardless of
779 	 * whether or not L1 wants to intercept "regular" #PF.
780 	 */
781 	if (is_guest_mode(vcpu) && fault->async_page_fault)
782 		kvm_queue_exception_vmexit(vcpu, PF_VECTOR,
783 					   true, fault->error_code,
784 					   true, fault->address);
785 	else
786 		kvm_queue_exception_e_p(vcpu, PF_VECTOR, fault->error_code,
787 					fault->address);
788 }
789 
kvm_inject_emulated_page_fault(struct kvm_vcpu * vcpu,struct x86_exception * fault)790 void kvm_inject_emulated_page_fault(struct kvm_vcpu *vcpu,
791 				    struct x86_exception *fault)
792 {
793 	struct kvm_mmu *fault_mmu;
794 	WARN_ON_ONCE(fault->vector != PF_VECTOR);
795 
796 	fault_mmu = fault->nested_page_fault ? vcpu->arch.mmu :
797 					       vcpu->arch.walk_mmu;
798 
799 	/*
800 	 * Invalidate the TLB entry for the faulting address, if it exists,
801 	 * else the access will fault indefinitely (and to emulate hardware).
802 	 */
803 	if ((fault->error_code & PFERR_PRESENT_MASK) &&
804 	    !(fault->error_code & PFERR_RSVD_MASK))
805 		kvm_mmu_invalidate_addr(vcpu, fault_mmu, fault->address,
806 					KVM_MMU_ROOT_CURRENT);
807 
808 	fault_mmu->inject_page_fault(vcpu, fault);
809 }
810 EXPORT_SYMBOL_GPL(kvm_inject_emulated_page_fault);
811 
kvm_inject_nmi(struct kvm_vcpu * vcpu)812 void kvm_inject_nmi(struct kvm_vcpu *vcpu)
813 {
814 	atomic_inc(&vcpu->arch.nmi_queued);
815 	kvm_make_request(KVM_REQ_NMI, vcpu);
816 }
817 
kvm_queue_exception_e(struct kvm_vcpu * vcpu,unsigned nr,u32 error_code)818 void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code)
819 {
820 	kvm_multiple_exception(vcpu, nr, true, error_code, false, 0, false);
821 }
822 EXPORT_SYMBOL_GPL(kvm_queue_exception_e);
823 
kvm_requeue_exception_e(struct kvm_vcpu * vcpu,unsigned nr,u32 error_code)824 void kvm_requeue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code)
825 {
826 	kvm_multiple_exception(vcpu, nr, true, error_code, false, 0, true);
827 }
828 EXPORT_SYMBOL_GPL(kvm_requeue_exception_e);
829 
830 /*
831  * Checks if cpl <= required_cpl; if true, return true.  Otherwise queue
832  * a #GP and return false.
833  */
kvm_require_cpl(struct kvm_vcpu * vcpu,int required_cpl)834 bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl)
835 {
836 	if (static_call(kvm_x86_get_cpl)(vcpu) <= required_cpl)
837 		return true;
838 	kvm_queue_exception_e(vcpu, GP_VECTOR, 0);
839 	return false;
840 }
841 
kvm_require_dr(struct kvm_vcpu * vcpu,int dr)842 bool kvm_require_dr(struct kvm_vcpu *vcpu, int dr)
843 {
844 	if ((dr != 4 && dr != 5) || !kvm_is_cr4_bit_set(vcpu, X86_CR4_DE))
845 		return true;
846 
847 	kvm_queue_exception(vcpu, UD_VECTOR);
848 	return false;
849 }
850 EXPORT_SYMBOL_GPL(kvm_require_dr);
851 
pdptr_rsvd_bits(struct kvm_vcpu * vcpu)852 static inline u64 pdptr_rsvd_bits(struct kvm_vcpu *vcpu)
853 {
854 	return vcpu->arch.reserved_gpa_bits | rsvd_bits(5, 8) | rsvd_bits(1, 2);
855 }
856 
857 /*
858  * Load the pae pdptrs.  Return 1 if they are all valid, 0 otherwise.
859  */
load_pdptrs(struct kvm_vcpu * vcpu,unsigned long cr3)860 int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3)
861 {
862 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
863 	gfn_t pdpt_gfn = cr3 >> PAGE_SHIFT;
864 	gpa_t real_gpa;
865 	int i;
866 	int ret;
867 	u64 pdpte[ARRAY_SIZE(mmu->pdptrs)];
868 
869 	/*
870 	 * If the MMU is nested, CR3 holds an L2 GPA and needs to be translated
871 	 * to an L1 GPA.
872 	 */
873 	real_gpa = kvm_translate_gpa(vcpu, mmu, gfn_to_gpa(pdpt_gfn),
874 				     PFERR_USER_MASK | PFERR_WRITE_MASK, NULL);
875 	if (real_gpa == INVALID_GPA)
876 		return 0;
877 
878 	/* Note the offset, PDPTRs are 32 byte aligned when using PAE paging. */
879 	ret = kvm_vcpu_read_guest_page(vcpu, gpa_to_gfn(real_gpa), pdpte,
880 				       cr3 & GENMASK(11, 5), sizeof(pdpte));
881 	if (ret < 0)
882 		return 0;
883 
884 	for (i = 0; i < ARRAY_SIZE(pdpte); ++i) {
885 		if ((pdpte[i] & PT_PRESENT_MASK) &&
886 		    (pdpte[i] & pdptr_rsvd_bits(vcpu))) {
887 			return 0;
888 		}
889 	}
890 
891 	/*
892 	 * Marking VCPU_EXREG_PDPTR dirty doesn't work for !tdp_enabled.
893 	 * Shadow page roots need to be reconstructed instead.
894 	 */
895 	if (!tdp_enabled && memcmp(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs)))
896 		kvm_mmu_free_roots(vcpu->kvm, mmu, KVM_MMU_ROOT_CURRENT);
897 
898 	memcpy(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs));
899 	kvm_register_mark_dirty(vcpu, VCPU_EXREG_PDPTR);
900 	kvm_make_request(KVM_REQ_LOAD_MMU_PGD, vcpu);
901 	vcpu->arch.pdptrs_from_userspace = false;
902 
903 	return 1;
904 }
905 EXPORT_SYMBOL_GPL(load_pdptrs);
906 
kvm_is_valid_cr0(struct kvm_vcpu * vcpu,unsigned long cr0)907 static bool kvm_is_valid_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
908 {
909 #ifdef CONFIG_X86_64
910 	if (cr0 & 0xffffffff00000000UL)
911 		return false;
912 #endif
913 
914 	if ((cr0 & X86_CR0_NW) && !(cr0 & X86_CR0_CD))
915 		return false;
916 
917 	if ((cr0 & X86_CR0_PG) && !(cr0 & X86_CR0_PE))
918 		return false;
919 
920 	return static_call(kvm_x86_is_valid_cr0)(vcpu, cr0);
921 }
922 
kvm_post_set_cr0(struct kvm_vcpu * vcpu,unsigned long old_cr0,unsigned long cr0)923 void kvm_post_set_cr0(struct kvm_vcpu *vcpu, unsigned long old_cr0, unsigned long cr0)
924 {
925 	/*
926 	 * CR0.WP is incorporated into the MMU role, but only for non-nested,
927 	 * indirect shadow MMUs.  If paging is disabled, no updates are needed
928 	 * as there are no permission bits to emulate.  If TDP is enabled, the
929 	 * MMU's metadata needs to be updated, e.g. so that emulating guest
930 	 * translations does the right thing, but there's no need to unload the
931 	 * root as CR0.WP doesn't affect SPTEs.
932 	 */
933 	if ((cr0 ^ old_cr0) == X86_CR0_WP) {
934 		if (!(cr0 & X86_CR0_PG))
935 			return;
936 
937 		if (tdp_enabled) {
938 			kvm_init_mmu(vcpu);
939 			return;
940 		}
941 	}
942 
943 	if ((cr0 ^ old_cr0) & X86_CR0_PG) {
944 		kvm_clear_async_pf_completion_queue(vcpu);
945 		kvm_async_pf_hash_reset(vcpu);
946 
947 		/*
948 		 * Clearing CR0.PG is defined to flush the TLB from the guest's
949 		 * perspective.
950 		 */
951 		if (!(cr0 & X86_CR0_PG))
952 			kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
953 	}
954 
955 	if ((cr0 ^ old_cr0) & KVM_MMU_CR0_ROLE_BITS)
956 		kvm_mmu_reset_context(vcpu);
957 
958 	if (((cr0 ^ old_cr0) & X86_CR0_CD) &&
959 	    kvm_mmu_honors_guest_mtrrs(vcpu->kvm) &&
960 	    !kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_CD_NW_CLEARED))
961 		kvm_zap_gfn_range(vcpu->kvm, 0, ~0ULL);
962 }
963 EXPORT_SYMBOL_GPL(kvm_post_set_cr0);
964 
kvm_set_cr0(struct kvm_vcpu * vcpu,unsigned long cr0)965 int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
966 {
967 	unsigned long old_cr0 = kvm_read_cr0(vcpu);
968 
969 	if (!kvm_is_valid_cr0(vcpu, cr0))
970 		return 1;
971 
972 	cr0 |= X86_CR0_ET;
973 
974 	/* Write to CR0 reserved bits are ignored, even on Intel. */
975 	cr0 &= ~CR0_RESERVED_BITS;
976 
977 #ifdef CONFIG_X86_64
978 	if ((vcpu->arch.efer & EFER_LME) && !is_paging(vcpu) &&
979 	    (cr0 & X86_CR0_PG)) {
980 		int cs_db, cs_l;
981 
982 		if (!is_pae(vcpu))
983 			return 1;
984 		static_call(kvm_x86_get_cs_db_l_bits)(vcpu, &cs_db, &cs_l);
985 		if (cs_l)
986 			return 1;
987 	}
988 #endif
989 	if (!(vcpu->arch.efer & EFER_LME) && (cr0 & X86_CR0_PG) &&
990 	    is_pae(vcpu) && ((cr0 ^ old_cr0) & X86_CR0_PDPTR_BITS) &&
991 	    !load_pdptrs(vcpu, kvm_read_cr3(vcpu)))
992 		return 1;
993 
994 	if (!(cr0 & X86_CR0_PG) &&
995 	    (is_64_bit_mode(vcpu) || kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE)))
996 		return 1;
997 
998 	static_call(kvm_x86_set_cr0)(vcpu, cr0);
999 
1000 	kvm_post_set_cr0(vcpu, old_cr0, cr0);
1001 
1002 	return 0;
1003 }
1004 EXPORT_SYMBOL_GPL(kvm_set_cr0);
1005 
kvm_lmsw(struct kvm_vcpu * vcpu,unsigned long msw)1006 void kvm_lmsw(struct kvm_vcpu *vcpu, unsigned long msw)
1007 {
1008 	(void)kvm_set_cr0(vcpu, kvm_read_cr0_bits(vcpu, ~0x0eul) | (msw & 0x0f));
1009 }
1010 EXPORT_SYMBOL_GPL(kvm_lmsw);
1011 
kvm_load_guest_xsave_state(struct kvm_vcpu * vcpu)1012 void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu)
1013 {
1014 	if (vcpu->arch.guest_state_protected)
1015 		return;
1016 
1017 	if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) {
1018 
1019 		if (vcpu->arch.xcr0 != host_xcr0)
1020 			xsetbv(XCR_XFEATURE_ENABLED_MASK, vcpu->arch.xcr0);
1021 
1022 		if (guest_can_use(vcpu, X86_FEATURE_XSAVES) &&
1023 		    vcpu->arch.ia32_xss != host_xss)
1024 			wrmsrl(MSR_IA32_XSS, vcpu->arch.ia32_xss);
1025 	}
1026 
1027 	if (cpu_feature_enabled(X86_FEATURE_PKU) &&
1028 	    vcpu->arch.pkru != vcpu->arch.host_pkru &&
1029 	    ((vcpu->arch.xcr0 & XFEATURE_MASK_PKRU) ||
1030 	     kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE)))
1031 		write_pkru(vcpu->arch.pkru);
1032 }
1033 EXPORT_SYMBOL_GPL(kvm_load_guest_xsave_state);
1034 
kvm_load_host_xsave_state(struct kvm_vcpu * vcpu)1035 void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu)
1036 {
1037 	if (vcpu->arch.guest_state_protected)
1038 		return;
1039 
1040 	if (cpu_feature_enabled(X86_FEATURE_PKU) &&
1041 	    ((vcpu->arch.xcr0 & XFEATURE_MASK_PKRU) ||
1042 	     kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE))) {
1043 		vcpu->arch.pkru = rdpkru();
1044 		if (vcpu->arch.pkru != vcpu->arch.host_pkru)
1045 			write_pkru(vcpu->arch.host_pkru);
1046 	}
1047 
1048 	if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) {
1049 
1050 		if (vcpu->arch.xcr0 != host_xcr0)
1051 			xsetbv(XCR_XFEATURE_ENABLED_MASK, host_xcr0);
1052 
1053 		if (guest_can_use(vcpu, X86_FEATURE_XSAVES) &&
1054 		    vcpu->arch.ia32_xss != host_xss)
1055 			wrmsrl(MSR_IA32_XSS, host_xss);
1056 	}
1057 
1058 }
1059 EXPORT_SYMBOL_GPL(kvm_load_host_xsave_state);
1060 
1061 #ifdef CONFIG_X86_64
kvm_guest_supported_xfd(struct kvm_vcpu * vcpu)1062 static inline u64 kvm_guest_supported_xfd(struct kvm_vcpu *vcpu)
1063 {
1064 	return vcpu->arch.guest_supported_xcr0 & XFEATURE_MASK_USER_DYNAMIC;
1065 }
1066 #endif
1067 
__kvm_set_xcr(struct kvm_vcpu * vcpu,u32 index,u64 xcr)1068 static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr)
1069 {
1070 	u64 xcr0 = xcr;
1071 	u64 old_xcr0 = vcpu->arch.xcr0;
1072 	u64 valid_bits;
1073 
1074 	/* Only support XCR_XFEATURE_ENABLED_MASK(xcr0) now  */
1075 	if (index != XCR_XFEATURE_ENABLED_MASK)
1076 		return 1;
1077 	if (!(xcr0 & XFEATURE_MASK_FP))
1078 		return 1;
1079 	if ((xcr0 & XFEATURE_MASK_YMM) && !(xcr0 & XFEATURE_MASK_SSE))
1080 		return 1;
1081 
1082 	/*
1083 	 * Do not allow the guest to set bits that we do not support
1084 	 * saving.  However, xcr0 bit 0 is always set, even if the
1085 	 * emulated CPU does not support XSAVE (see kvm_vcpu_reset()).
1086 	 */
1087 	valid_bits = vcpu->arch.guest_supported_xcr0 | XFEATURE_MASK_FP;
1088 	if (xcr0 & ~valid_bits)
1089 		return 1;
1090 
1091 	if ((!(xcr0 & XFEATURE_MASK_BNDREGS)) !=
1092 	    (!(xcr0 & XFEATURE_MASK_BNDCSR)))
1093 		return 1;
1094 
1095 	if (xcr0 & XFEATURE_MASK_AVX512) {
1096 		if (!(xcr0 & XFEATURE_MASK_YMM))
1097 			return 1;
1098 		if ((xcr0 & XFEATURE_MASK_AVX512) != XFEATURE_MASK_AVX512)
1099 			return 1;
1100 	}
1101 
1102 	if ((xcr0 & XFEATURE_MASK_XTILE) &&
1103 	    ((xcr0 & XFEATURE_MASK_XTILE) != XFEATURE_MASK_XTILE))
1104 		return 1;
1105 
1106 	vcpu->arch.xcr0 = xcr0;
1107 
1108 	if ((xcr0 ^ old_xcr0) & XFEATURE_MASK_EXTEND)
1109 		kvm_update_cpuid_runtime(vcpu);
1110 	return 0;
1111 }
1112 
kvm_emulate_xsetbv(struct kvm_vcpu * vcpu)1113 int kvm_emulate_xsetbv(struct kvm_vcpu *vcpu)
1114 {
1115 	/* Note, #UD due to CR4.OSXSAVE=0 has priority over the intercept. */
1116 	if (static_call(kvm_x86_get_cpl)(vcpu) != 0 ||
1117 	    __kvm_set_xcr(vcpu, kvm_rcx_read(vcpu), kvm_read_edx_eax(vcpu))) {
1118 		kvm_inject_gp(vcpu, 0);
1119 		return 1;
1120 	}
1121 
1122 	return kvm_skip_emulated_instruction(vcpu);
1123 }
1124 EXPORT_SYMBOL_GPL(kvm_emulate_xsetbv);
1125 
__kvm_is_valid_cr4(struct kvm_vcpu * vcpu,unsigned long cr4)1126 bool __kvm_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
1127 {
1128 	if (cr4 & cr4_reserved_bits)
1129 		return false;
1130 
1131 	if (cr4 & vcpu->arch.cr4_guest_rsvd_bits)
1132 		return false;
1133 
1134 	return true;
1135 }
1136 EXPORT_SYMBOL_GPL(__kvm_is_valid_cr4);
1137 
kvm_is_valid_cr4(struct kvm_vcpu * vcpu,unsigned long cr4)1138 static bool kvm_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
1139 {
1140 	return __kvm_is_valid_cr4(vcpu, cr4) &&
1141 	       static_call(kvm_x86_is_valid_cr4)(vcpu, cr4);
1142 }
1143 
kvm_post_set_cr4(struct kvm_vcpu * vcpu,unsigned long old_cr4,unsigned long cr4)1144 void kvm_post_set_cr4(struct kvm_vcpu *vcpu, unsigned long old_cr4, unsigned long cr4)
1145 {
1146 	if ((cr4 ^ old_cr4) & KVM_MMU_CR4_ROLE_BITS)
1147 		kvm_mmu_reset_context(vcpu);
1148 
1149 	/*
1150 	 * If CR4.PCIDE is changed 0 -> 1, there is no need to flush the TLB
1151 	 * according to the SDM; however, stale prev_roots could be reused
1152 	 * incorrectly in the future after a MOV to CR3 with NOFLUSH=1, so we
1153 	 * free them all.  This is *not* a superset of KVM_REQ_TLB_FLUSH_GUEST
1154 	 * or KVM_REQ_TLB_FLUSH_CURRENT, because the hardware TLB is not flushed,
1155 	 * so fall through.
1156 	 */
1157 	if (!tdp_enabled &&
1158 	    (cr4 & X86_CR4_PCIDE) && !(old_cr4 & X86_CR4_PCIDE))
1159 		kvm_mmu_unload(vcpu);
1160 
1161 	/*
1162 	 * The TLB has to be flushed for all PCIDs if any of the following
1163 	 * (architecturally required) changes happen:
1164 	 * - CR4.PCIDE is changed from 1 to 0
1165 	 * - CR4.PGE is toggled
1166 	 *
1167 	 * This is a superset of KVM_REQ_TLB_FLUSH_CURRENT.
1168 	 */
1169 	if (((cr4 ^ old_cr4) & X86_CR4_PGE) ||
1170 	    (!(cr4 & X86_CR4_PCIDE) && (old_cr4 & X86_CR4_PCIDE)))
1171 		kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
1172 
1173 	/*
1174 	 * The TLB has to be flushed for the current PCID if any of the
1175 	 * following (architecturally required) changes happen:
1176 	 * - CR4.SMEP is changed from 0 to 1
1177 	 * - CR4.PAE is toggled
1178 	 */
1179 	else if (((cr4 ^ old_cr4) & X86_CR4_PAE) ||
1180 		 ((cr4 & X86_CR4_SMEP) && !(old_cr4 & X86_CR4_SMEP)))
1181 		kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
1182 
1183 }
1184 EXPORT_SYMBOL_GPL(kvm_post_set_cr4);
1185 
kvm_set_cr4(struct kvm_vcpu * vcpu,unsigned long cr4)1186 int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
1187 {
1188 	unsigned long old_cr4 = kvm_read_cr4(vcpu);
1189 
1190 	if (!kvm_is_valid_cr4(vcpu, cr4))
1191 		return 1;
1192 
1193 	if (is_long_mode(vcpu)) {
1194 		if (!(cr4 & X86_CR4_PAE))
1195 			return 1;
1196 		if ((cr4 ^ old_cr4) & X86_CR4_LA57)
1197 			return 1;
1198 	} else if (is_paging(vcpu) && (cr4 & X86_CR4_PAE)
1199 		   && ((cr4 ^ old_cr4) & X86_CR4_PDPTR_BITS)
1200 		   && !load_pdptrs(vcpu, kvm_read_cr3(vcpu)))
1201 		return 1;
1202 
1203 	if ((cr4 & X86_CR4_PCIDE) && !(old_cr4 & X86_CR4_PCIDE)) {
1204 		/* PCID can not be enabled when cr3[11:0]!=000H or EFER.LMA=0 */
1205 		if ((kvm_read_cr3(vcpu) & X86_CR3_PCID_MASK) || !is_long_mode(vcpu))
1206 			return 1;
1207 	}
1208 
1209 	static_call(kvm_x86_set_cr4)(vcpu, cr4);
1210 
1211 	kvm_post_set_cr4(vcpu, old_cr4, cr4);
1212 
1213 	return 0;
1214 }
1215 EXPORT_SYMBOL_GPL(kvm_set_cr4);
1216 
kvm_invalidate_pcid(struct kvm_vcpu * vcpu,unsigned long pcid)1217 static void kvm_invalidate_pcid(struct kvm_vcpu *vcpu, unsigned long pcid)
1218 {
1219 	struct kvm_mmu *mmu = vcpu->arch.mmu;
1220 	unsigned long roots_to_free = 0;
1221 	int i;
1222 
1223 	/*
1224 	 * MOV CR3 and INVPCID are usually not intercepted when using TDP, but
1225 	 * this is reachable when running EPT=1 and unrestricted_guest=0,  and
1226 	 * also via the emulator.  KVM's TDP page tables are not in the scope of
1227 	 * the invalidation, but the guest's TLB entries need to be flushed as
1228 	 * the CPU may have cached entries in its TLB for the target PCID.
1229 	 */
1230 	if (unlikely(tdp_enabled)) {
1231 		kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
1232 		return;
1233 	}
1234 
1235 	/*
1236 	 * If neither the current CR3 nor any of the prev_roots use the given
1237 	 * PCID, then nothing needs to be done here because a resync will
1238 	 * happen anyway before switching to any other CR3.
1239 	 */
1240 	if (kvm_get_active_pcid(vcpu) == pcid) {
1241 		kvm_make_request(KVM_REQ_MMU_SYNC, vcpu);
1242 		kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
1243 	}
1244 
1245 	/*
1246 	 * If PCID is disabled, there is no need to free prev_roots even if the
1247 	 * PCIDs for them are also 0, because MOV to CR3 always flushes the TLB
1248 	 * with PCIDE=0.
1249 	 */
1250 	if (!kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE))
1251 		return;
1252 
1253 	for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++)
1254 		if (kvm_get_pcid(vcpu, mmu->prev_roots[i].pgd) == pcid)
1255 			roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i);
1256 
1257 	kvm_mmu_free_roots(vcpu->kvm, mmu, roots_to_free);
1258 }
1259 
kvm_set_cr3(struct kvm_vcpu * vcpu,unsigned long cr3)1260 int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
1261 {
1262 	bool skip_tlb_flush = false;
1263 	unsigned long pcid = 0;
1264 #ifdef CONFIG_X86_64
1265 	if (kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE)) {
1266 		skip_tlb_flush = cr3 & X86_CR3_PCID_NOFLUSH;
1267 		cr3 &= ~X86_CR3_PCID_NOFLUSH;
1268 		pcid = cr3 & X86_CR3_PCID_MASK;
1269 	}
1270 #endif
1271 
1272 	/* PDPTRs are always reloaded for PAE paging. */
1273 	if (cr3 == kvm_read_cr3(vcpu) && !is_pae_paging(vcpu))
1274 		goto handle_tlb_flush;
1275 
1276 	/*
1277 	 * Do not condition the GPA check on long mode, this helper is used to
1278 	 * stuff CR3, e.g. for RSM emulation, and there is no guarantee that
1279 	 * the current vCPU mode is accurate.
1280 	 */
1281 	if (!kvm_vcpu_is_legal_cr3(vcpu, cr3))
1282 		return 1;
1283 
1284 	if (is_pae_paging(vcpu) && !load_pdptrs(vcpu, cr3))
1285 		return 1;
1286 
1287 	if (cr3 != kvm_read_cr3(vcpu))
1288 		kvm_mmu_new_pgd(vcpu, cr3);
1289 
1290 	vcpu->arch.cr3 = cr3;
1291 	kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3);
1292 	/* Do not call post_set_cr3, we do not get here for confidential guests.  */
1293 
1294 handle_tlb_flush:
1295 	/*
1296 	 * A load of CR3 that flushes the TLB flushes only the current PCID,
1297 	 * even if PCID is disabled, in which case PCID=0 is flushed.  It's a
1298 	 * moot point in the end because _disabling_ PCID will flush all PCIDs,
1299 	 * and it's impossible to use a non-zero PCID when PCID is disabled,
1300 	 * i.e. only PCID=0 can be relevant.
1301 	 */
1302 	if (!skip_tlb_flush)
1303 		kvm_invalidate_pcid(vcpu, pcid);
1304 
1305 	return 0;
1306 }
1307 EXPORT_SYMBOL_GPL(kvm_set_cr3);
1308 
kvm_set_cr8(struct kvm_vcpu * vcpu,unsigned long cr8)1309 int kvm_set_cr8(struct kvm_vcpu *vcpu, unsigned long cr8)
1310 {
1311 	if (cr8 & CR8_RESERVED_BITS)
1312 		return 1;
1313 	if (lapic_in_kernel(vcpu))
1314 		kvm_lapic_set_tpr(vcpu, cr8);
1315 	else
1316 		vcpu->arch.cr8 = cr8;
1317 	return 0;
1318 }
1319 EXPORT_SYMBOL_GPL(kvm_set_cr8);
1320 
kvm_get_cr8(struct kvm_vcpu * vcpu)1321 unsigned long kvm_get_cr8(struct kvm_vcpu *vcpu)
1322 {
1323 	if (lapic_in_kernel(vcpu))
1324 		return kvm_lapic_get_cr8(vcpu);
1325 	else
1326 		return vcpu->arch.cr8;
1327 }
1328 EXPORT_SYMBOL_GPL(kvm_get_cr8);
1329 
kvm_update_dr0123(struct kvm_vcpu * vcpu)1330 static void kvm_update_dr0123(struct kvm_vcpu *vcpu)
1331 {
1332 	int i;
1333 
1334 	if (!(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP)) {
1335 		for (i = 0; i < KVM_NR_DB_REGS; i++)
1336 			vcpu->arch.eff_db[i] = vcpu->arch.db[i];
1337 	}
1338 }
1339 
kvm_update_dr7(struct kvm_vcpu * vcpu)1340 void kvm_update_dr7(struct kvm_vcpu *vcpu)
1341 {
1342 	unsigned long dr7;
1343 
1344 	if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP)
1345 		dr7 = vcpu->arch.guest_debug_dr7;
1346 	else
1347 		dr7 = vcpu->arch.dr7;
1348 	static_call(kvm_x86_set_dr7)(vcpu, dr7);
1349 	vcpu->arch.switch_db_regs &= ~KVM_DEBUGREG_BP_ENABLED;
1350 	if (dr7 & DR7_BP_EN_MASK)
1351 		vcpu->arch.switch_db_regs |= KVM_DEBUGREG_BP_ENABLED;
1352 }
1353 EXPORT_SYMBOL_GPL(kvm_update_dr7);
1354 
kvm_dr6_fixed(struct kvm_vcpu * vcpu)1355 static u64 kvm_dr6_fixed(struct kvm_vcpu *vcpu)
1356 {
1357 	u64 fixed = DR6_FIXED_1;
1358 
1359 	if (!guest_cpuid_has(vcpu, X86_FEATURE_RTM))
1360 		fixed |= DR6_RTM;
1361 
1362 	if (!guest_cpuid_has(vcpu, X86_FEATURE_BUS_LOCK_DETECT))
1363 		fixed |= DR6_BUS_LOCK;
1364 	return fixed;
1365 }
1366 
kvm_set_dr(struct kvm_vcpu * vcpu,int dr,unsigned long val)1367 int kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val)
1368 {
1369 	size_t size = ARRAY_SIZE(vcpu->arch.db);
1370 
1371 	switch (dr) {
1372 	case 0 ... 3:
1373 		vcpu->arch.db[array_index_nospec(dr, size)] = val;
1374 		if (!(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP))
1375 			vcpu->arch.eff_db[dr] = val;
1376 		break;
1377 	case 4:
1378 	case 6:
1379 		if (!kvm_dr6_valid(val))
1380 			return 1; /* #GP */
1381 		vcpu->arch.dr6 = (val & DR6_VOLATILE) | kvm_dr6_fixed(vcpu);
1382 		break;
1383 	case 5:
1384 	default: /* 7 */
1385 		if (!kvm_dr7_valid(val))
1386 			return 1; /* #GP */
1387 		vcpu->arch.dr7 = (val & DR7_VOLATILE) | DR7_FIXED_1;
1388 		kvm_update_dr7(vcpu);
1389 		break;
1390 	}
1391 
1392 	return 0;
1393 }
1394 EXPORT_SYMBOL_GPL(kvm_set_dr);
1395 
kvm_get_dr(struct kvm_vcpu * vcpu,int dr)1396 unsigned long kvm_get_dr(struct kvm_vcpu *vcpu, int dr)
1397 {
1398 	size_t size = ARRAY_SIZE(vcpu->arch.db);
1399 
1400 	switch (dr) {
1401 	case 0 ... 3:
1402 		return vcpu->arch.db[array_index_nospec(dr, size)];
1403 	case 4:
1404 	case 6:
1405 		return vcpu->arch.dr6;
1406 	case 5:
1407 	default: /* 7 */
1408 		return vcpu->arch.dr7;
1409 	}
1410 }
1411 EXPORT_SYMBOL_GPL(kvm_get_dr);
1412 
kvm_emulate_rdpmc(struct kvm_vcpu * vcpu)1413 int kvm_emulate_rdpmc(struct kvm_vcpu *vcpu)
1414 {
1415 	u32 ecx = kvm_rcx_read(vcpu);
1416 	u64 data;
1417 
1418 	if (kvm_pmu_rdpmc(vcpu, ecx, &data)) {
1419 		kvm_inject_gp(vcpu, 0);
1420 		return 1;
1421 	}
1422 
1423 	kvm_rax_write(vcpu, (u32)data);
1424 	kvm_rdx_write(vcpu, data >> 32);
1425 	return kvm_skip_emulated_instruction(vcpu);
1426 }
1427 EXPORT_SYMBOL_GPL(kvm_emulate_rdpmc);
1428 
1429 /*
1430  * The three MSR lists(msrs_to_save, emulated_msrs, msr_based_features) track
1431  * the set of MSRs that KVM exposes to userspace through KVM_GET_MSRS,
1432  * KVM_SET_MSRS, and KVM_GET_MSR_INDEX_LIST.  msrs_to_save holds MSRs that
1433  * require host support, i.e. should be probed via RDMSR.  emulated_msrs holds
1434  * MSRs that KVM emulates without strictly requiring host support.
1435  * msr_based_features holds MSRs that enumerate features, i.e. are effectively
1436  * CPUID leafs.  Note, msr_based_features isn't mutually exclusive with
1437  * msrs_to_save and emulated_msrs.
1438  */
1439 
1440 static const u32 msrs_to_save_base[] = {
1441 	MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP,
1442 	MSR_STAR,
1443 #ifdef CONFIG_X86_64
1444 	MSR_CSTAR, MSR_KERNEL_GS_BASE, MSR_SYSCALL_MASK, MSR_LSTAR,
1445 #endif
1446 	MSR_IA32_TSC, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA,
1447 	MSR_IA32_FEAT_CTL, MSR_IA32_BNDCFGS, MSR_TSC_AUX,
1448 	MSR_IA32_SPEC_CTRL, MSR_IA32_TSX_CTRL,
1449 	MSR_IA32_RTIT_CTL, MSR_IA32_RTIT_STATUS, MSR_IA32_RTIT_CR3_MATCH,
1450 	MSR_IA32_RTIT_OUTPUT_BASE, MSR_IA32_RTIT_OUTPUT_MASK,
1451 	MSR_IA32_RTIT_ADDR0_A, MSR_IA32_RTIT_ADDR0_B,
1452 	MSR_IA32_RTIT_ADDR1_A, MSR_IA32_RTIT_ADDR1_B,
1453 	MSR_IA32_RTIT_ADDR2_A, MSR_IA32_RTIT_ADDR2_B,
1454 	MSR_IA32_RTIT_ADDR3_A, MSR_IA32_RTIT_ADDR3_B,
1455 	MSR_IA32_UMWAIT_CONTROL,
1456 
1457 	MSR_IA32_XFD, MSR_IA32_XFD_ERR,
1458 };
1459 
1460 static const u32 msrs_to_save_pmu[] = {
1461 	MSR_ARCH_PERFMON_FIXED_CTR0, MSR_ARCH_PERFMON_FIXED_CTR1,
1462 	MSR_ARCH_PERFMON_FIXED_CTR0 + 2,
1463 	MSR_CORE_PERF_FIXED_CTR_CTRL, MSR_CORE_PERF_GLOBAL_STATUS,
1464 	MSR_CORE_PERF_GLOBAL_CTRL, MSR_CORE_PERF_GLOBAL_OVF_CTRL,
1465 	MSR_IA32_PEBS_ENABLE, MSR_IA32_DS_AREA, MSR_PEBS_DATA_CFG,
1466 
1467 	/* This part of MSRs should match KVM_INTEL_PMC_MAX_GENERIC. */
1468 	MSR_ARCH_PERFMON_PERFCTR0, MSR_ARCH_PERFMON_PERFCTR1,
1469 	MSR_ARCH_PERFMON_PERFCTR0 + 2, MSR_ARCH_PERFMON_PERFCTR0 + 3,
1470 	MSR_ARCH_PERFMON_PERFCTR0 + 4, MSR_ARCH_PERFMON_PERFCTR0 + 5,
1471 	MSR_ARCH_PERFMON_PERFCTR0 + 6, MSR_ARCH_PERFMON_PERFCTR0 + 7,
1472 	MSR_ARCH_PERFMON_EVENTSEL0, MSR_ARCH_PERFMON_EVENTSEL1,
1473 	MSR_ARCH_PERFMON_EVENTSEL0 + 2, MSR_ARCH_PERFMON_EVENTSEL0 + 3,
1474 	MSR_ARCH_PERFMON_EVENTSEL0 + 4, MSR_ARCH_PERFMON_EVENTSEL0 + 5,
1475 	MSR_ARCH_PERFMON_EVENTSEL0 + 6, MSR_ARCH_PERFMON_EVENTSEL0 + 7,
1476 
1477 	MSR_K7_EVNTSEL0, MSR_K7_EVNTSEL1, MSR_K7_EVNTSEL2, MSR_K7_EVNTSEL3,
1478 	MSR_K7_PERFCTR0, MSR_K7_PERFCTR1, MSR_K7_PERFCTR2, MSR_K7_PERFCTR3,
1479 
1480 	/* This part of MSRs should match KVM_AMD_PMC_MAX_GENERIC. */
1481 	MSR_F15H_PERF_CTL0, MSR_F15H_PERF_CTL1, MSR_F15H_PERF_CTL2,
1482 	MSR_F15H_PERF_CTL3, MSR_F15H_PERF_CTL4, MSR_F15H_PERF_CTL5,
1483 	MSR_F15H_PERF_CTR0, MSR_F15H_PERF_CTR1, MSR_F15H_PERF_CTR2,
1484 	MSR_F15H_PERF_CTR3, MSR_F15H_PERF_CTR4, MSR_F15H_PERF_CTR5,
1485 
1486 	MSR_AMD64_PERF_CNTR_GLOBAL_CTL,
1487 	MSR_AMD64_PERF_CNTR_GLOBAL_STATUS,
1488 	MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR,
1489 };
1490 
1491 static u32 msrs_to_save[ARRAY_SIZE(msrs_to_save_base) +
1492 			ARRAY_SIZE(msrs_to_save_pmu)];
1493 static unsigned num_msrs_to_save;
1494 
1495 static const u32 emulated_msrs_all[] = {
1496 	MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK,
1497 	MSR_KVM_SYSTEM_TIME_NEW, MSR_KVM_WALL_CLOCK_NEW,
1498 
1499 #ifdef CONFIG_KVM_HYPERV
1500 	HV_X64_MSR_GUEST_OS_ID, HV_X64_MSR_HYPERCALL,
1501 	HV_X64_MSR_TIME_REF_COUNT, HV_X64_MSR_REFERENCE_TSC,
1502 	HV_X64_MSR_TSC_FREQUENCY, HV_X64_MSR_APIC_FREQUENCY,
1503 	HV_X64_MSR_CRASH_P0, HV_X64_MSR_CRASH_P1, HV_X64_MSR_CRASH_P2,
1504 	HV_X64_MSR_CRASH_P3, HV_X64_MSR_CRASH_P4, HV_X64_MSR_CRASH_CTL,
1505 	HV_X64_MSR_RESET,
1506 	HV_X64_MSR_VP_INDEX,
1507 	HV_X64_MSR_VP_RUNTIME,
1508 	HV_X64_MSR_SCONTROL,
1509 	HV_X64_MSR_STIMER0_CONFIG,
1510 	HV_X64_MSR_VP_ASSIST_PAGE,
1511 	HV_X64_MSR_REENLIGHTENMENT_CONTROL, HV_X64_MSR_TSC_EMULATION_CONTROL,
1512 	HV_X64_MSR_TSC_EMULATION_STATUS, HV_X64_MSR_TSC_INVARIANT_CONTROL,
1513 	HV_X64_MSR_SYNDBG_OPTIONS,
1514 	HV_X64_MSR_SYNDBG_CONTROL, HV_X64_MSR_SYNDBG_STATUS,
1515 	HV_X64_MSR_SYNDBG_SEND_BUFFER, HV_X64_MSR_SYNDBG_RECV_BUFFER,
1516 	HV_X64_MSR_SYNDBG_PENDING_BUFFER,
1517 #endif
1518 
1519 	MSR_KVM_ASYNC_PF_EN, MSR_KVM_STEAL_TIME,
1520 	MSR_KVM_PV_EOI_EN, MSR_KVM_ASYNC_PF_INT, MSR_KVM_ASYNC_PF_ACK,
1521 
1522 	MSR_IA32_TSC_ADJUST,
1523 	MSR_IA32_TSC_DEADLINE,
1524 	MSR_IA32_ARCH_CAPABILITIES,
1525 	MSR_IA32_PERF_CAPABILITIES,
1526 	MSR_IA32_MISC_ENABLE,
1527 	MSR_IA32_MCG_STATUS,
1528 	MSR_IA32_MCG_CTL,
1529 	MSR_IA32_MCG_EXT_CTL,
1530 	MSR_IA32_SMBASE,
1531 	MSR_SMI_COUNT,
1532 	MSR_PLATFORM_INFO,
1533 	MSR_MISC_FEATURES_ENABLES,
1534 	MSR_AMD64_VIRT_SPEC_CTRL,
1535 	MSR_AMD64_TSC_RATIO,
1536 	MSR_IA32_POWER_CTL,
1537 	MSR_IA32_UCODE_REV,
1538 
1539 	/*
1540 	 * KVM always supports the "true" VMX control MSRs, even if the host
1541 	 * does not.  The VMX MSRs as a whole are considered "emulated" as KVM
1542 	 * doesn't strictly require them to exist in the host (ignoring that
1543 	 * KVM would refuse to load in the first place if the core set of MSRs
1544 	 * aren't supported).
1545 	 */
1546 	MSR_IA32_VMX_BASIC,
1547 	MSR_IA32_VMX_TRUE_PINBASED_CTLS,
1548 	MSR_IA32_VMX_TRUE_PROCBASED_CTLS,
1549 	MSR_IA32_VMX_TRUE_EXIT_CTLS,
1550 	MSR_IA32_VMX_TRUE_ENTRY_CTLS,
1551 	MSR_IA32_VMX_MISC,
1552 	MSR_IA32_VMX_CR0_FIXED0,
1553 	MSR_IA32_VMX_CR4_FIXED0,
1554 	MSR_IA32_VMX_VMCS_ENUM,
1555 	MSR_IA32_VMX_PROCBASED_CTLS2,
1556 	MSR_IA32_VMX_EPT_VPID_CAP,
1557 	MSR_IA32_VMX_VMFUNC,
1558 
1559 	MSR_K7_HWCR,
1560 	MSR_KVM_POLL_CONTROL,
1561 };
1562 
1563 static u32 emulated_msrs[ARRAY_SIZE(emulated_msrs_all)];
1564 static unsigned num_emulated_msrs;
1565 
1566 /*
1567  * List of MSRs that control the existence of MSR-based features, i.e. MSRs
1568  * that are effectively CPUID leafs.  VMX MSRs are also included in the set of
1569  * feature MSRs, but are handled separately to allow expedited lookups.
1570  */
1571 static const u32 msr_based_features_all_except_vmx[] = {
1572 	MSR_AMD64_DE_CFG,
1573 	MSR_IA32_UCODE_REV,
1574 	MSR_IA32_ARCH_CAPABILITIES,
1575 	MSR_IA32_PERF_CAPABILITIES,
1576 };
1577 
1578 static u32 msr_based_features[ARRAY_SIZE(msr_based_features_all_except_vmx) +
1579 			      (KVM_LAST_EMULATED_VMX_MSR - KVM_FIRST_EMULATED_VMX_MSR + 1)];
1580 static unsigned int num_msr_based_features;
1581 
1582 /*
1583  * All feature MSRs except uCode revID, which tracks the currently loaded uCode
1584  * patch, are immutable once the vCPU model is defined.
1585  */
kvm_is_immutable_feature_msr(u32 msr)1586 static bool kvm_is_immutable_feature_msr(u32 msr)
1587 {
1588 	int i;
1589 
1590 	if (msr >= KVM_FIRST_EMULATED_VMX_MSR && msr <= KVM_LAST_EMULATED_VMX_MSR)
1591 		return true;
1592 
1593 	for (i = 0; i < ARRAY_SIZE(msr_based_features_all_except_vmx); i++) {
1594 		if (msr == msr_based_features_all_except_vmx[i])
1595 			return msr != MSR_IA32_UCODE_REV;
1596 	}
1597 
1598 	return false;
1599 }
1600 
1601 /*
1602  * Some IA32_ARCH_CAPABILITIES bits have dependencies on MSRs that KVM
1603  * does not yet virtualize. These include:
1604  *   10 - MISC_PACKAGE_CTRLS
1605  *   11 - ENERGY_FILTERING_CTL
1606  *   12 - DOITM
1607  *   18 - FB_CLEAR_CTRL
1608  *   21 - XAPIC_DISABLE_STATUS
1609  *   23 - OVERCLOCKING_STATUS
1610  */
1611 
1612 #define KVM_SUPPORTED_ARCH_CAP \
1613 	(ARCH_CAP_RDCL_NO | ARCH_CAP_IBRS_ALL | ARCH_CAP_RSBA | \
1614 	 ARCH_CAP_SKIP_VMENTRY_L1DFLUSH | ARCH_CAP_SSB_NO | ARCH_CAP_MDS_NO | \
1615 	 ARCH_CAP_PSCHANGE_MC_NO | ARCH_CAP_TSX_CTRL_MSR | ARCH_CAP_TAA_NO | \
1616 	 ARCH_CAP_SBDR_SSDP_NO | ARCH_CAP_FBSDP_NO | ARCH_CAP_PSDP_NO | \
1617 	 ARCH_CAP_FB_CLEAR | ARCH_CAP_RRSBA | ARCH_CAP_PBRSB_NO | ARCH_CAP_GDS_NO | \
1618 	 ARCH_CAP_RFDS_NO | ARCH_CAP_RFDS_CLEAR | ARCH_CAP_BHI_NO)
1619 
kvm_get_arch_capabilities(void)1620 static u64 kvm_get_arch_capabilities(void)
1621 {
1622 	u64 data = host_arch_capabilities & KVM_SUPPORTED_ARCH_CAP;
1623 
1624 	/*
1625 	 * If nx_huge_pages is enabled, KVM's shadow paging will ensure that
1626 	 * the nested hypervisor runs with NX huge pages.  If it is not,
1627 	 * L1 is anyway vulnerable to ITLB_MULTIHIT exploits from other
1628 	 * L1 guests, so it need not worry about its own (L2) guests.
1629 	 */
1630 	data |= ARCH_CAP_PSCHANGE_MC_NO;
1631 
1632 	/*
1633 	 * If we're doing cache flushes (either "always" or "cond")
1634 	 * we will do one whenever the guest does a vmlaunch/vmresume.
1635 	 * If an outer hypervisor is doing the cache flush for us
1636 	 * (ARCH_CAP_SKIP_VMENTRY_L1DFLUSH), we can safely pass that
1637 	 * capability to the guest too, and if EPT is disabled we're not
1638 	 * vulnerable.  Overall, only VMENTER_L1D_FLUSH_NEVER will
1639 	 * require a nested hypervisor to do a flush of its own.
1640 	 */
1641 	if (l1tf_vmx_mitigation != VMENTER_L1D_FLUSH_NEVER)
1642 		data |= ARCH_CAP_SKIP_VMENTRY_L1DFLUSH;
1643 
1644 	if (!boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN))
1645 		data |= ARCH_CAP_RDCL_NO;
1646 	if (!boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS))
1647 		data |= ARCH_CAP_SSB_NO;
1648 	if (!boot_cpu_has_bug(X86_BUG_MDS))
1649 		data |= ARCH_CAP_MDS_NO;
1650 	if (!boot_cpu_has_bug(X86_BUG_RFDS))
1651 		data |= ARCH_CAP_RFDS_NO;
1652 
1653 	if (!boot_cpu_has(X86_FEATURE_RTM)) {
1654 		/*
1655 		 * If RTM=0 because the kernel has disabled TSX, the host might
1656 		 * have TAA_NO or TSX_CTRL.  Clear TAA_NO (the guest sees RTM=0
1657 		 * and therefore knows that there cannot be TAA) but keep
1658 		 * TSX_CTRL: some buggy userspaces leave it set on tsx=on hosts,
1659 		 * and we want to allow migrating those guests to tsx=off hosts.
1660 		 */
1661 		data &= ~ARCH_CAP_TAA_NO;
1662 	} else if (!boot_cpu_has_bug(X86_BUG_TAA)) {
1663 		data |= ARCH_CAP_TAA_NO;
1664 	} else {
1665 		/*
1666 		 * Nothing to do here; we emulate TSX_CTRL if present on the
1667 		 * host so the guest can choose between disabling TSX or
1668 		 * using VERW to clear CPU buffers.
1669 		 */
1670 	}
1671 
1672 	if (!boot_cpu_has_bug(X86_BUG_GDS) || gds_ucode_mitigated())
1673 		data |= ARCH_CAP_GDS_NO;
1674 
1675 	return data;
1676 }
1677 
kvm_get_msr_feature(struct kvm_msr_entry * msr)1678 static int kvm_get_msr_feature(struct kvm_msr_entry *msr)
1679 {
1680 	switch (msr->index) {
1681 	case MSR_IA32_ARCH_CAPABILITIES:
1682 		msr->data = kvm_get_arch_capabilities();
1683 		break;
1684 	case MSR_IA32_PERF_CAPABILITIES:
1685 		msr->data = kvm_caps.supported_perf_cap;
1686 		break;
1687 	case MSR_IA32_UCODE_REV:
1688 		rdmsrl_safe(msr->index, &msr->data);
1689 		break;
1690 	default:
1691 		return static_call(kvm_x86_get_msr_feature)(msr);
1692 	}
1693 	return 0;
1694 }
1695 
do_get_msr_feature(struct kvm_vcpu * vcpu,unsigned index,u64 * data)1696 static int do_get_msr_feature(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
1697 {
1698 	struct kvm_msr_entry msr;
1699 	int r;
1700 
1701 	/* Unconditionally clear the output for simplicity */
1702 	msr.data = 0;
1703 	msr.index = index;
1704 	r = kvm_get_msr_feature(&msr);
1705 
1706 	if (r == KVM_MSR_RET_INVALID && kvm_msr_ignored_check(index, 0, false))
1707 		r = 0;
1708 
1709 	*data = msr.data;
1710 
1711 	return r;
1712 }
1713 
__kvm_valid_efer(struct kvm_vcpu * vcpu,u64 efer)1714 static bool __kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer)
1715 {
1716 	if (efer & EFER_AUTOIBRS && !guest_cpuid_has(vcpu, X86_FEATURE_AUTOIBRS))
1717 		return false;
1718 
1719 	if (efer & EFER_FFXSR && !guest_cpuid_has(vcpu, X86_FEATURE_FXSR_OPT))
1720 		return false;
1721 
1722 	if (efer & EFER_SVME && !guest_cpuid_has(vcpu, X86_FEATURE_SVM))
1723 		return false;
1724 
1725 	if (efer & (EFER_LME | EFER_LMA) &&
1726 	    !guest_cpuid_has(vcpu, X86_FEATURE_LM))
1727 		return false;
1728 
1729 	if (efer & EFER_NX && !guest_cpuid_has(vcpu, X86_FEATURE_NX))
1730 		return false;
1731 
1732 	return true;
1733 
1734 }
kvm_valid_efer(struct kvm_vcpu * vcpu,u64 efer)1735 bool kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer)
1736 {
1737 	if (efer & efer_reserved_bits)
1738 		return false;
1739 
1740 	return __kvm_valid_efer(vcpu, efer);
1741 }
1742 EXPORT_SYMBOL_GPL(kvm_valid_efer);
1743 
set_efer(struct kvm_vcpu * vcpu,struct msr_data * msr_info)1744 static int set_efer(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
1745 {
1746 	u64 old_efer = vcpu->arch.efer;
1747 	u64 efer = msr_info->data;
1748 	int r;
1749 
1750 	if (efer & efer_reserved_bits)
1751 		return 1;
1752 
1753 	if (!msr_info->host_initiated) {
1754 		if (!__kvm_valid_efer(vcpu, efer))
1755 			return 1;
1756 
1757 		if (is_paging(vcpu) &&
1758 		    (vcpu->arch.efer & EFER_LME) != (efer & EFER_LME))
1759 			return 1;
1760 	}
1761 
1762 	efer &= ~EFER_LMA;
1763 	efer |= vcpu->arch.efer & EFER_LMA;
1764 
1765 	r = static_call(kvm_x86_set_efer)(vcpu, efer);
1766 	if (r) {
1767 		WARN_ON(r > 0);
1768 		return r;
1769 	}
1770 
1771 	if ((efer ^ old_efer) & KVM_MMU_EFER_ROLE_BITS)
1772 		kvm_mmu_reset_context(vcpu);
1773 
1774 	if (!static_cpu_has(X86_FEATURE_XSAVES) &&
1775 	    (efer & EFER_SVME))
1776 		kvm_hv_xsaves_xsavec_maybe_warn(vcpu);
1777 
1778 	return 0;
1779 }
1780 
kvm_enable_efer_bits(u64 mask)1781 void kvm_enable_efer_bits(u64 mask)
1782 {
1783        efer_reserved_bits &= ~mask;
1784 }
1785 EXPORT_SYMBOL_GPL(kvm_enable_efer_bits);
1786 
kvm_msr_allowed(struct kvm_vcpu * vcpu,u32 index,u32 type)1787 bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type)
1788 {
1789 	struct kvm_x86_msr_filter *msr_filter;
1790 	struct msr_bitmap_range *ranges;
1791 	struct kvm *kvm = vcpu->kvm;
1792 	bool allowed;
1793 	int idx;
1794 	u32 i;
1795 
1796 	/* x2APIC MSRs do not support filtering. */
1797 	if (index >= 0x800 && index <= 0x8ff)
1798 		return true;
1799 
1800 	idx = srcu_read_lock(&kvm->srcu);
1801 
1802 	msr_filter = srcu_dereference(kvm->arch.msr_filter, &kvm->srcu);
1803 	if (!msr_filter) {
1804 		allowed = true;
1805 		goto out;
1806 	}
1807 
1808 	allowed = msr_filter->default_allow;
1809 	ranges = msr_filter->ranges;
1810 
1811 	for (i = 0; i < msr_filter->count; i++) {
1812 		u32 start = ranges[i].base;
1813 		u32 end = start + ranges[i].nmsrs;
1814 		u32 flags = ranges[i].flags;
1815 		unsigned long *bitmap = ranges[i].bitmap;
1816 
1817 		if ((index >= start) && (index < end) && (flags & type)) {
1818 			allowed = test_bit(index - start, bitmap);
1819 			break;
1820 		}
1821 	}
1822 
1823 out:
1824 	srcu_read_unlock(&kvm->srcu, idx);
1825 
1826 	return allowed;
1827 }
1828 EXPORT_SYMBOL_GPL(kvm_msr_allowed);
1829 
1830 /*
1831  * Write @data into the MSR specified by @index.  Select MSR specific fault
1832  * checks are bypassed if @host_initiated is %true.
1833  * Returns 0 on success, non-0 otherwise.
1834  * Assumes vcpu_load() was already called.
1835  */
__kvm_set_msr(struct kvm_vcpu * vcpu,u32 index,u64 data,bool host_initiated)1836 static int __kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data,
1837 			 bool host_initiated)
1838 {
1839 	struct msr_data msr;
1840 
1841 	switch (index) {
1842 	case MSR_FS_BASE:
1843 	case MSR_GS_BASE:
1844 	case MSR_KERNEL_GS_BASE:
1845 	case MSR_CSTAR:
1846 	case MSR_LSTAR:
1847 		if (is_noncanonical_address(data, vcpu))
1848 			return 1;
1849 		break;
1850 	case MSR_IA32_SYSENTER_EIP:
1851 	case MSR_IA32_SYSENTER_ESP:
1852 		/*
1853 		 * IA32_SYSENTER_ESP and IA32_SYSENTER_EIP cause #GP if
1854 		 * non-canonical address is written on Intel but not on
1855 		 * AMD (which ignores the top 32-bits, because it does
1856 		 * not implement 64-bit SYSENTER).
1857 		 *
1858 		 * 64-bit code should hence be able to write a non-canonical
1859 		 * value on AMD.  Making the address canonical ensures that
1860 		 * vmentry does not fail on Intel after writing a non-canonical
1861 		 * value, and that something deterministic happens if the guest
1862 		 * invokes 64-bit SYSENTER.
1863 		 */
1864 		data = __canonical_address(data, vcpu_virt_addr_bits(vcpu));
1865 		break;
1866 	case MSR_TSC_AUX:
1867 		if (!kvm_is_supported_user_return_msr(MSR_TSC_AUX))
1868 			return 1;
1869 
1870 		if (!host_initiated &&
1871 		    !guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) &&
1872 		    !guest_cpuid_has(vcpu, X86_FEATURE_RDPID))
1873 			return 1;
1874 
1875 		/*
1876 		 * Per Intel's SDM, bits 63:32 are reserved, but AMD's APM has
1877 		 * incomplete and conflicting architectural behavior.  Current
1878 		 * AMD CPUs completely ignore bits 63:32, i.e. they aren't
1879 		 * reserved and always read as zeros.  Enforce Intel's reserved
1880 		 * bits check if and only if the guest CPU is Intel, and clear
1881 		 * the bits in all other cases.  This ensures cross-vendor
1882 		 * migration will provide consistent behavior for the guest.
1883 		 */
1884 		if (guest_cpuid_is_intel(vcpu) && (data >> 32) != 0)
1885 			return 1;
1886 
1887 		data = (u32)data;
1888 		break;
1889 	}
1890 
1891 	msr.data = data;
1892 	msr.index = index;
1893 	msr.host_initiated = host_initiated;
1894 
1895 	return static_call(kvm_x86_set_msr)(vcpu, &msr);
1896 }
1897 
kvm_set_msr_ignored_check(struct kvm_vcpu * vcpu,u32 index,u64 data,bool host_initiated)1898 static int kvm_set_msr_ignored_check(struct kvm_vcpu *vcpu,
1899 				     u32 index, u64 data, bool host_initiated)
1900 {
1901 	int ret = __kvm_set_msr(vcpu, index, data, host_initiated);
1902 
1903 	if (ret == KVM_MSR_RET_INVALID)
1904 		if (kvm_msr_ignored_check(index, data, true))
1905 			ret = 0;
1906 
1907 	return ret;
1908 }
1909 
1910 /*
1911  * Read the MSR specified by @index into @data.  Select MSR specific fault
1912  * checks are bypassed if @host_initiated is %true.
1913  * Returns 0 on success, non-0 otherwise.
1914  * Assumes vcpu_load() was already called.
1915  */
__kvm_get_msr(struct kvm_vcpu * vcpu,u32 index,u64 * data,bool host_initiated)1916 int __kvm_get_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data,
1917 		  bool host_initiated)
1918 {
1919 	struct msr_data msr;
1920 	int ret;
1921 
1922 	switch (index) {
1923 	case MSR_TSC_AUX:
1924 		if (!kvm_is_supported_user_return_msr(MSR_TSC_AUX))
1925 			return 1;
1926 
1927 		if (!host_initiated &&
1928 		    !guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) &&
1929 		    !guest_cpuid_has(vcpu, X86_FEATURE_RDPID))
1930 			return 1;
1931 		break;
1932 	}
1933 
1934 	msr.index = index;
1935 	msr.host_initiated = host_initiated;
1936 
1937 	ret = static_call(kvm_x86_get_msr)(vcpu, &msr);
1938 	if (!ret)
1939 		*data = msr.data;
1940 	return ret;
1941 }
1942 
kvm_get_msr_ignored_check(struct kvm_vcpu * vcpu,u32 index,u64 * data,bool host_initiated)1943 static int kvm_get_msr_ignored_check(struct kvm_vcpu *vcpu,
1944 				     u32 index, u64 *data, bool host_initiated)
1945 {
1946 	int ret = __kvm_get_msr(vcpu, index, data, host_initiated);
1947 
1948 	if (ret == KVM_MSR_RET_INVALID) {
1949 		/* Unconditionally clear *data for simplicity */
1950 		*data = 0;
1951 		if (kvm_msr_ignored_check(index, 0, false))
1952 			ret = 0;
1953 	}
1954 
1955 	return ret;
1956 }
1957 
kvm_get_msr_with_filter(struct kvm_vcpu * vcpu,u32 index,u64 * data)1958 static int kvm_get_msr_with_filter(struct kvm_vcpu *vcpu, u32 index, u64 *data)
1959 {
1960 	if (!kvm_msr_allowed(vcpu, index, KVM_MSR_FILTER_READ))
1961 		return KVM_MSR_RET_FILTERED;
1962 	return kvm_get_msr_ignored_check(vcpu, index, data, false);
1963 }
1964 
kvm_set_msr_with_filter(struct kvm_vcpu * vcpu,u32 index,u64 data)1965 static int kvm_set_msr_with_filter(struct kvm_vcpu *vcpu, u32 index, u64 data)
1966 {
1967 	if (!kvm_msr_allowed(vcpu, index, KVM_MSR_FILTER_WRITE))
1968 		return KVM_MSR_RET_FILTERED;
1969 	return kvm_set_msr_ignored_check(vcpu, index, data, false);
1970 }
1971 
kvm_get_msr(struct kvm_vcpu * vcpu,u32 index,u64 * data)1972 int kvm_get_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data)
1973 {
1974 	return kvm_get_msr_ignored_check(vcpu, index, data, false);
1975 }
1976 EXPORT_SYMBOL_GPL(kvm_get_msr);
1977 
kvm_set_msr(struct kvm_vcpu * vcpu,u32 index,u64 data)1978 int kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data)
1979 {
1980 	return kvm_set_msr_ignored_check(vcpu, index, data, false);
1981 }
1982 EXPORT_SYMBOL_GPL(kvm_set_msr);
1983 
complete_userspace_rdmsr(struct kvm_vcpu * vcpu)1984 static void complete_userspace_rdmsr(struct kvm_vcpu *vcpu)
1985 {
1986 	if (!vcpu->run->msr.error) {
1987 		kvm_rax_write(vcpu, (u32)vcpu->run->msr.data);
1988 		kvm_rdx_write(vcpu, vcpu->run->msr.data >> 32);
1989 	}
1990 }
1991 
complete_emulated_msr_access(struct kvm_vcpu * vcpu)1992 static int complete_emulated_msr_access(struct kvm_vcpu *vcpu)
1993 {
1994 	return complete_emulated_insn_gp(vcpu, vcpu->run->msr.error);
1995 }
1996 
complete_emulated_rdmsr(struct kvm_vcpu * vcpu)1997 static int complete_emulated_rdmsr(struct kvm_vcpu *vcpu)
1998 {
1999 	complete_userspace_rdmsr(vcpu);
2000 	return complete_emulated_msr_access(vcpu);
2001 }
2002 
complete_fast_msr_access(struct kvm_vcpu * vcpu)2003 static int complete_fast_msr_access(struct kvm_vcpu *vcpu)
2004 {
2005 	return static_call(kvm_x86_complete_emulated_msr)(vcpu, vcpu->run->msr.error);
2006 }
2007 
complete_fast_rdmsr(struct kvm_vcpu * vcpu)2008 static int complete_fast_rdmsr(struct kvm_vcpu *vcpu)
2009 {
2010 	complete_userspace_rdmsr(vcpu);
2011 	return complete_fast_msr_access(vcpu);
2012 }
2013 
kvm_msr_reason(int r)2014 static u64 kvm_msr_reason(int r)
2015 {
2016 	switch (r) {
2017 	case KVM_MSR_RET_INVALID:
2018 		return KVM_MSR_EXIT_REASON_UNKNOWN;
2019 	case KVM_MSR_RET_FILTERED:
2020 		return KVM_MSR_EXIT_REASON_FILTER;
2021 	default:
2022 		return KVM_MSR_EXIT_REASON_INVAL;
2023 	}
2024 }
2025 
kvm_msr_user_space(struct kvm_vcpu * vcpu,u32 index,u32 exit_reason,u64 data,int (* completion)(struct kvm_vcpu * vcpu),int r)2026 static int kvm_msr_user_space(struct kvm_vcpu *vcpu, u32 index,
2027 			      u32 exit_reason, u64 data,
2028 			      int (*completion)(struct kvm_vcpu *vcpu),
2029 			      int r)
2030 {
2031 	u64 msr_reason = kvm_msr_reason(r);
2032 
2033 	/* Check if the user wanted to know about this MSR fault */
2034 	if (!(vcpu->kvm->arch.user_space_msr_mask & msr_reason))
2035 		return 0;
2036 
2037 	vcpu->run->exit_reason = exit_reason;
2038 	vcpu->run->msr.error = 0;
2039 	memset(vcpu->run->msr.pad, 0, sizeof(vcpu->run->msr.pad));
2040 	vcpu->run->msr.reason = msr_reason;
2041 	vcpu->run->msr.index = index;
2042 	vcpu->run->msr.data = data;
2043 	vcpu->arch.complete_userspace_io = completion;
2044 
2045 	return 1;
2046 }
2047 
kvm_emulate_rdmsr(struct kvm_vcpu * vcpu)2048 int kvm_emulate_rdmsr(struct kvm_vcpu *vcpu)
2049 {
2050 	u32 ecx = kvm_rcx_read(vcpu);
2051 	u64 data;
2052 	int r;
2053 
2054 	r = kvm_get_msr_with_filter(vcpu, ecx, &data);
2055 
2056 	if (!r) {
2057 		trace_kvm_msr_read(ecx, data);
2058 
2059 		kvm_rax_write(vcpu, data & -1u);
2060 		kvm_rdx_write(vcpu, (data >> 32) & -1u);
2061 	} else {
2062 		/* MSR read failed? See if we should ask user space */
2063 		if (kvm_msr_user_space(vcpu, ecx, KVM_EXIT_X86_RDMSR, 0,
2064 				       complete_fast_rdmsr, r))
2065 			return 0;
2066 		trace_kvm_msr_read_ex(ecx);
2067 	}
2068 
2069 	return static_call(kvm_x86_complete_emulated_msr)(vcpu, r);
2070 }
2071 EXPORT_SYMBOL_GPL(kvm_emulate_rdmsr);
2072 
kvm_emulate_wrmsr(struct kvm_vcpu * vcpu)2073 int kvm_emulate_wrmsr(struct kvm_vcpu *vcpu)
2074 {
2075 	u32 ecx = kvm_rcx_read(vcpu);
2076 	u64 data = kvm_read_edx_eax(vcpu);
2077 	int r;
2078 
2079 	r = kvm_set_msr_with_filter(vcpu, ecx, data);
2080 
2081 	if (!r) {
2082 		trace_kvm_msr_write(ecx, data);
2083 	} else {
2084 		/* MSR write failed? See if we should ask user space */
2085 		if (kvm_msr_user_space(vcpu, ecx, KVM_EXIT_X86_WRMSR, data,
2086 				       complete_fast_msr_access, r))
2087 			return 0;
2088 		/* Signal all other negative errors to userspace */
2089 		if (r < 0)
2090 			return r;
2091 		trace_kvm_msr_write_ex(ecx, data);
2092 	}
2093 
2094 	return static_call(kvm_x86_complete_emulated_msr)(vcpu, r);
2095 }
2096 EXPORT_SYMBOL_GPL(kvm_emulate_wrmsr);
2097 
kvm_emulate_as_nop(struct kvm_vcpu * vcpu)2098 int kvm_emulate_as_nop(struct kvm_vcpu *vcpu)
2099 {
2100 	return kvm_skip_emulated_instruction(vcpu);
2101 }
2102 
kvm_emulate_invd(struct kvm_vcpu * vcpu)2103 int kvm_emulate_invd(struct kvm_vcpu *vcpu)
2104 {
2105 	/* Treat an INVD instruction as a NOP and just skip it. */
2106 	return kvm_emulate_as_nop(vcpu);
2107 }
2108 EXPORT_SYMBOL_GPL(kvm_emulate_invd);
2109 
kvm_handle_invalid_op(struct kvm_vcpu * vcpu)2110 int kvm_handle_invalid_op(struct kvm_vcpu *vcpu)
2111 {
2112 	kvm_queue_exception(vcpu, UD_VECTOR);
2113 	return 1;
2114 }
2115 EXPORT_SYMBOL_GPL(kvm_handle_invalid_op);
2116 
2117 
kvm_emulate_monitor_mwait(struct kvm_vcpu * vcpu,const char * insn)2118 static int kvm_emulate_monitor_mwait(struct kvm_vcpu *vcpu, const char *insn)
2119 {
2120 	if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MWAIT_NEVER_UD_FAULTS) &&
2121 	    !guest_cpuid_has(vcpu, X86_FEATURE_MWAIT))
2122 		return kvm_handle_invalid_op(vcpu);
2123 
2124 	pr_warn_once("%s instruction emulated as NOP!\n", insn);
2125 	return kvm_emulate_as_nop(vcpu);
2126 }
kvm_emulate_mwait(struct kvm_vcpu * vcpu)2127 int kvm_emulate_mwait(struct kvm_vcpu *vcpu)
2128 {
2129 	return kvm_emulate_monitor_mwait(vcpu, "MWAIT");
2130 }
2131 EXPORT_SYMBOL_GPL(kvm_emulate_mwait);
2132 
kvm_emulate_monitor(struct kvm_vcpu * vcpu)2133 int kvm_emulate_monitor(struct kvm_vcpu *vcpu)
2134 {
2135 	return kvm_emulate_monitor_mwait(vcpu, "MONITOR");
2136 }
2137 EXPORT_SYMBOL_GPL(kvm_emulate_monitor);
2138 
kvm_vcpu_exit_request(struct kvm_vcpu * vcpu)2139 static inline bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu)
2140 {
2141 	xfer_to_guest_mode_prepare();
2142 	return vcpu->mode == EXITING_GUEST_MODE || kvm_request_pending(vcpu) ||
2143 		xfer_to_guest_mode_work_pending();
2144 }
2145 
2146 /*
2147  * The fast path for frequent and performance sensitive wrmsr emulation,
2148  * i.e. the sending of IPI, sending IPI early in the VM-Exit flow reduces
2149  * the latency of virtual IPI by avoiding the expensive bits of transitioning
2150  * from guest to host, e.g. reacquiring KVM's SRCU lock. In contrast to the
2151  * other cases which must be called after interrupts are enabled on the host.
2152  */
handle_fastpath_set_x2apic_icr_irqoff(struct kvm_vcpu * vcpu,u64 data)2153 static int handle_fastpath_set_x2apic_icr_irqoff(struct kvm_vcpu *vcpu, u64 data)
2154 {
2155 	if (!lapic_in_kernel(vcpu) || !apic_x2apic_mode(vcpu->arch.apic))
2156 		return 1;
2157 
2158 	if (((data & APIC_SHORT_MASK) == APIC_DEST_NOSHORT) &&
2159 	    ((data & APIC_DEST_MASK) == APIC_DEST_PHYSICAL) &&
2160 	    ((data & APIC_MODE_MASK) == APIC_DM_FIXED) &&
2161 	    ((u32)(data >> 32) != X2APIC_BROADCAST))
2162 		return kvm_x2apic_icr_write(vcpu->arch.apic, data);
2163 
2164 	return 1;
2165 }
2166 
handle_fastpath_set_tscdeadline(struct kvm_vcpu * vcpu,u64 data)2167 static int handle_fastpath_set_tscdeadline(struct kvm_vcpu *vcpu, u64 data)
2168 {
2169 	if (!kvm_can_use_hv_timer(vcpu))
2170 		return 1;
2171 
2172 	kvm_set_lapic_tscdeadline_msr(vcpu, data);
2173 	return 0;
2174 }
2175 
handle_fastpath_set_msr_irqoff(struct kvm_vcpu * vcpu)2176 fastpath_t handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vcpu)
2177 {
2178 	u32 msr = kvm_rcx_read(vcpu);
2179 	u64 data;
2180 	fastpath_t ret = EXIT_FASTPATH_NONE;
2181 
2182 	kvm_vcpu_srcu_read_lock(vcpu);
2183 
2184 	switch (msr) {
2185 	case APIC_BASE_MSR + (APIC_ICR >> 4):
2186 		data = kvm_read_edx_eax(vcpu);
2187 		if (!handle_fastpath_set_x2apic_icr_irqoff(vcpu, data)) {
2188 			kvm_skip_emulated_instruction(vcpu);
2189 			ret = EXIT_FASTPATH_EXIT_HANDLED;
2190 		}
2191 		break;
2192 	case MSR_IA32_TSC_DEADLINE:
2193 		data = kvm_read_edx_eax(vcpu);
2194 		if (!handle_fastpath_set_tscdeadline(vcpu, data)) {
2195 			kvm_skip_emulated_instruction(vcpu);
2196 			ret = EXIT_FASTPATH_REENTER_GUEST;
2197 		}
2198 		break;
2199 	default:
2200 		break;
2201 	}
2202 
2203 	if (ret != EXIT_FASTPATH_NONE)
2204 		trace_kvm_msr_write(msr, data);
2205 
2206 	kvm_vcpu_srcu_read_unlock(vcpu);
2207 
2208 	return ret;
2209 }
2210 EXPORT_SYMBOL_GPL(handle_fastpath_set_msr_irqoff);
2211 
2212 /*
2213  * Adapt set_msr() to msr_io()'s calling convention
2214  */
do_get_msr(struct kvm_vcpu * vcpu,unsigned index,u64 * data)2215 static int do_get_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
2216 {
2217 	return kvm_get_msr_ignored_check(vcpu, index, data, true);
2218 }
2219 
do_set_msr(struct kvm_vcpu * vcpu,unsigned index,u64 * data)2220 static int do_set_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
2221 {
2222 	u64 val;
2223 
2224 	/*
2225 	 * Disallow writes to immutable feature MSRs after KVM_RUN.  KVM does
2226 	 * not support modifying the guest vCPU model on the fly, e.g. changing
2227 	 * the nVMX capabilities while L2 is running is nonsensical.  Allow
2228 	 * writes of the same value, e.g. to allow userspace to blindly stuff
2229 	 * all MSRs when emulating RESET.
2230 	 */
2231 	if (kvm_vcpu_has_run(vcpu) && kvm_is_immutable_feature_msr(index) &&
2232 	    (do_get_msr(vcpu, index, &val) || *data != val))
2233 		return -EINVAL;
2234 
2235 	return kvm_set_msr_ignored_check(vcpu, index, *data, true);
2236 }
2237 
2238 #ifdef CONFIG_X86_64
2239 struct pvclock_clock {
2240 	int vclock_mode;
2241 	u64 cycle_last;
2242 	u64 mask;
2243 	u32 mult;
2244 	u32 shift;
2245 	u64 base_cycles;
2246 	u64 offset;
2247 };
2248 
2249 struct pvclock_gtod_data {
2250 	seqcount_t	seq;
2251 
2252 	struct pvclock_clock clock; /* extract of a clocksource struct */
2253 	struct pvclock_clock raw_clock; /* extract of a clocksource struct */
2254 
2255 	ktime_t		offs_boot;
2256 	u64		wall_time_sec;
2257 };
2258 
2259 static struct pvclock_gtod_data pvclock_gtod_data;
2260 
update_pvclock_gtod(struct timekeeper * tk)2261 static void update_pvclock_gtod(struct timekeeper *tk)
2262 {
2263 	struct pvclock_gtod_data *vdata = &pvclock_gtod_data;
2264 
2265 	write_seqcount_begin(&vdata->seq);
2266 
2267 	/* copy pvclock gtod data */
2268 	vdata->clock.vclock_mode	= tk->tkr_mono.clock->vdso_clock_mode;
2269 	vdata->clock.cycle_last		= tk->tkr_mono.cycle_last;
2270 	vdata->clock.mask		= tk->tkr_mono.mask;
2271 	vdata->clock.mult		= tk->tkr_mono.mult;
2272 	vdata->clock.shift		= tk->tkr_mono.shift;
2273 	vdata->clock.base_cycles	= tk->tkr_mono.xtime_nsec;
2274 	vdata->clock.offset		= tk->tkr_mono.base;
2275 
2276 	vdata->raw_clock.vclock_mode	= tk->tkr_raw.clock->vdso_clock_mode;
2277 	vdata->raw_clock.cycle_last	= tk->tkr_raw.cycle_last;
2278 	vdata->raw_clock.mask		= tk->tkr_raw.mask;
2279 	vdata->raw_clock.mult		= tk->tkr_raw.mult;
2280 	vdata->raw_clock.shift		= tk->tkr_raw.shift;
2281 	vdata->raw_clock.base_cycles	= tk->tkr_raw.xtime_nsec;
2282 	vdata->raw_clock.offset		= tk->tkr_raw.base;
2283 
2284 	vdata->wall_time_sec            = tk->xtime_sec;
2285 
2286 	vdata->offs_boot		= tk->offs_boot;
2287 
2288 	write_seqcount_end(&vdata->seq);
2289 }
2290 
get_kvmclock_base_ns(void)2291 static s64 get_kvmclock_base_ns(void)
2292 {
2293 	/* Count up from boot time, but with the frequency of the raw clock.  */
2294 	return ktime_to_ns(ktime_add(ktime_get_raw(), pvclock_gtod_data.offs_boot));
2295 }
2296 #else
get_kvmclock_base_ns(void)2297 static s64 get_kvmclock_base_ns(void)
2298 {
2299 	/* Master clock not used, so we can just use CLOCK_BOOTTIME.  */
2300 	return ktime_get_boottime_ns();
2301 }
2302 #endif
2303 
kvm_write_wall_clock(struct kvm * kvm,gpa_t wall_clock,int sec_hi_ofs)2304 static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock, int sec_hi_ofs)
2305 {
2306 	int version;
2307 	int r;
2308 	struct pvclock_wall_clock wc;
2309 	u32 wc_sec_hi;
2310 	u64 wall_nsec;
2311 
2312 	if (!wall_clock)
2313 		return;
2314 
2315 	r = kvm_read_guest(kvm, wall_clock, &version, sizeof(version));
2316 	if (r)
2317 		return;
2318 
2319 	if (version & 1)
2320 		++version;  /* first time write, random junk */
2321 
2322 	++version;
2323 
2324 	if (kvm_write_guest(kvm, wall_clock, &version, sizeof(version)))
2325 		return;
2326 
2327 	wall_nsec = kvm_get_wall_clock_epoch(kvm);
2328 
2329 	wc.nsec = do_div(wall_nsec, NSEC_PER_SEC);
2330 	wc.sec = (u32)wall_nsec; /* overflow in 2106 guest time */
2331 	wc.version = version;
2332 
2333 	kvm_write_guest(kvm, wall_clock, &wc, sizeof(wc));
2334 
2335 	if (sec_hi_ofs) {
2336 		wc_sec_hi = wall_nsec >> 32;
2337 		kvm_write_guest(kvm, wall_clock + sec_hi_ofs,
2338 				&wc_sec_hi, sizeof(wc_sec_hi));
2339 	}
2340 
2341 	version++;
2342 	kvm_write_guest(kvm, wall_clock, &version, sizeof(version));
2343 }
2344 
kvm_write_system_time(struct kvm_vcpu * vcpu,gpa_t system_time,bool old_msr,bool host_initiated)2345 static void kvm_write_system_time(struct kvm_vcpu *vcpu, gpa_t system_time,
2346 				  bool old_msr, bool host_initiated)
2347 {
2348 	struct kvm_arch *ka = &vcpu->kvm->arch;
2349 
2350 	if (vcpu->vcpu_id == 0 && !host_initiated) {
2351 		if (ka->boot_vcpu_runs_old_kvmclock != old_msr)
2352 			kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
2353 
2354 		ka->boot_vcpu_runs_old_kvmclock = old_msr;
2355 	}
2356 
2357 	vcpu->arch.time = system_time;
2358 	kvm_make_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu);
2359 
2360 	/* we verify if the enable bit is set... */
2361 	if (system_time & 1)
2362 		kvm_gpc_activate(&vcpu->arch.pv_time, system_time & ~1ULL,
2363 				 sizeof(struct pvclock_vcpu_time_info));
2364 	else
2365 		kvm_gpc_deactivate(&vcpu->arch.pv_time);
2366 
2367 	return;
2368 }
2369 
div_frac(uint32_t dividend,uint32_t divisor)2370 static uint32_t div_frac(uint32_t dividend, uint32_t divisor)
2371 {
2372 	do_shl32_div32(dividend, divisor);
2373 	return dividend;
2374 }
2375 
kvm_get_time_scale(uint64_t scaled_hz,uint64_t base_hz,s8 * pshift,u32 * pmultiplier)2376 static void kvm_get_time_scale(uint64_t scaled_hz, uint64_t base_hz,
2377 			       s8 *pshift, u32 *pmultiplier)
2378 {
2379 	uint64_t scaled64;
2380 	int32_t  shift = 0;
2381 	uint64_t tps64;
2382 	uint32_t tps32;
2383 
2384 	tps64 = base_hz;
2385 	scaled64 = scaled_hz;
2386 	while (tps64 > scaled64*2 || tps64 & 0xffffffff00000000ULL) {
2387 		tps64 >>= 1;
2388 		shift--;
2389 	}
2390 
2391 	tps32 = (uint32_t)tps64;
2392 	while (tps32 <= scaled64 || scaled64 & 0xffffffff00000000ULL) {
2393 		if (scaled64 & 0xffffffff00000000ULL || tps32 & 0x80000000)
2394 			scaled64 >>= 1;
2395 		else
2396 			tps32 <<= 1;
2397 		shift++;
2398 	}
2399 
2400 	*pshift = shift;
2401 	*pmultiplier = div_frac(scaled64, tps32);
2402 }
2403 
2404 #ifdef CONFIG_X86_64
2405 static atomic_t kvm_guest_has_master_clock = ATOMIC_INIT(0);
2406 #endif
2407 
2408 static DEFINE_PER_CPU(unsigned long, cpu_tsc_khz);
2409 static unsigned long max_tsc_khz;
2410 
adjust_tsc_khz(u32 khz,s32 ppm)2411 static u32 adjust_tsc_khz(u32 khz, s32 ppm)
2412 {
2413 	u64 v = (u64)khz * (1000000 + ppm);
2414 	do_div(v, 1000000);
2415 	return v;
2416 }
2417 
2418 static void kvm_vcpu_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 l1_multiplier);
2419 
set_tsc_khz(struct kvm_vcpu * vcpu,u32 user_tsc_khz,bool scale)2420 static int set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale)
2421 {
2422 	u64 ratio;
2423 
2424 	/* Guest TSC same frequency as host TSC? */
2425 	if (!scale) {
2426 		kvm_vcpu_write_tsc_multiplier(vcpu, kvm_caps.default_tsc_scaling_ratio);
2427 		return 0;
2428 	}
2429 
2430 	/* TSC scaling supported? */
2431 	if (!kvm_caps.has_tsc_control) {
2432 		if (user_tsc_khz > tsc_khz) {
2433 			vcpu->arch.tsc_catchup = 1;
2434 			vcpu->arch.tsc_always_catchup = 1;
2435 			return 0;
2436 		} else {
2437 			pr_warn_ratelimited("user requested TSC rate below hardware speed\n");
2438 			return -1;
2439 		}
2440 	}
2441 
2442 	/* TSC scaling required  - calculate ratio */
2443 	ratio = mul_u64_u32_div(1ULL << kvm_caps.tsc_scaling_ratio_frac_bits,
2444 				user_tsc_khz, tsc_khz);
2445 
2446 	if (ratio == 0 || ratio >= kvm_caps.max_tsc_scaling_ratio) {
2447 		pr_warn_ratelimited("Invalid TSC scaling ratio - virtual-tsc-khz=%u\n",
2448 			            user_tsc_khz);
2449 		return -1;
2450 	}
2451 
2452 	kvm_vcpu_write_tsc_multiplier(vcpu, ratio);
2453 	return 0;
2454 }
2455 
kvm_set_tsc_khz(struct kvm_vcpu * vcpu,u32 user_tsc_khz)2456 static int kvm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz)
2457 {
2458 	u32 thresh_lo, thresh_hi;
2459 	int use_scaling = 0;
2460 
2461 	/* tsc_khz can be zero if TSC calibration fails */
2462 	if (user_tsc_khz == 0) {
2463 		/* set tsc_scaling_ratio to a safe value */
2464 		kvm_vcpu_write_tsc_multiplier(vcpu, kvm_caps.default_tsc_scaling_ratio);
2465 		return -1;
2466 	}
2467 
2468 	/* Compute a scale to convert nanoseconds in TSC cycles */
2469 	kvm_get_time_scale(user_tsc_khz * 1000LL, NSEC_PER_SEC,
2470 			   &vcpu->arch.virtual_tsc_shift,
2471 			   &vcpu->arch.virtual_tsc_mult);
2472 	vcpu->arch.virtual_tsc_khz = user_tsc_khz;
2473 
2474 	/*
2475 	 * Compute the variation in TSC rate which is acceptable
2476 	 * within the range of tolerance and decide if the
2477 	 * rate being applied is within that bounds of the hardware
2478 	 * rate.  If so, no scaling or compensation need be done.
2479 	 */
2480 	thresh_lo = adjust_tsc_khz(tsc_khz, -tsc_tolerance_ppm);
2481 	thresh_hi = adjust_tsc_khz(tsc_khz, tsc_tolerance_ppm);
2482 	if (user_tsc_khz < thresh_lo || user_tsc_khz > thresh_hi) {
2483 		pr_debug("requested TSC rate %u falls outside tolerance [%u,%u]\n",
2484 			 user_tsc_khz, thresh_lo, thresh_hi);
2485 		use_scaling = 1;
2486 	}
2487 	return set_tsc_khz(vcpu, user_tsc_khz, use_scaling);
2488 }
2489 
compute_guest_tsc(struct kvm_vcpu * vcpu,s64 kernel_ns)2490 static u64 compute_guest_tsc(struct kvm_vcpu *vcpu, s64 kernel_ns)
2491 {
2492 	u64 tsc = pvclock_scale_delta(kernel_ns-vcpu->arch.this_tsc_nsec,
2493 				      vcpu->arch.virtual_tsc_mult,
2494 				      vcpu->arch.virtual_tsc_shift);
2495 	tsc += vcpu->arch.this_tsc_write;
2496 	return tsc;
2497 }
2498 
2499 #ifdef CONFIG_X86_64
gtod_is_based_on_tsc(int mode)2500 static inline bool gtod_is_based_on_tsc(int mode)
2501 {
2502 	return mode == VDSO_CLOCKMODE_TSC || mode == VDSO_CLOCKMODE_HVCLOCK;
2503 }
2504 #endif
2505 
kvm_track_tsc_matching(struct kvm_vcpu * vcpu,bool new_generation)2506 static void kvm_track_tsc_matching(struct kvm_vcpu *vcpu, bool new_generation)
2507 {
2508 #ifdef CONFIG_X86_64
2509 	struct kvm_arch *ka = &vcpu->kvm->arch;
2510 	struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
2511 
2512 	/*
2513 	 * To use the masterclock, the host clocksource must be based on TSC
2514 	 * and all vCPUs must have matching TSCs.  Note, the count for matching
2515 	 * vCPUs doesn't include the reference vCPU, hence "+1".
2516 	 */
2517 	bool use_master_clock = (ka->nr_vcpus_matched_tsc + 1 ==
2518 				 atomic_read(&vcpu->kvm->online_vcpus)) &&
2519 				gtod_is_based_on_tsc(gtod->clock.vclock_mode);
2520 
2521 	/*
2522 	 * Request a masterclock update if the masterclock needs to be toggled
2523 	 * on/off, or when starting a new generation and the masterclock is
2524 	 * enabled (compute_guest_tsc() requires the masterclock snapshot to be
2525 	 * taken _after_ the new generation is created).
2526 	 */
2527 	if ((ka->use_master_clock && new_generation) ||
2528 	    (ka->use_master_clock != use_master_clock))
2529 		kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
2530 
2531 	trace_kvm_track_tsc(vcpu->vcpu_id, ka->nr_vcpus_matched_tsc,
2532 			    atomic_read(&vcpu->kvm->online_vcpus),
2533 		            ka->use_master_clock, gtod->clock.vclock_mode);
2534 #endif
2535 }
2536 
2537 /*
2538  * Multiply tsc by a fixed point number represented by ratio.
2539  *
2540  * The most significant 64-N bits (mult) of ratio represent the
2541  * integral part of the fixed point number; the remaining N bits
2542  * (frac) represent the fractional part, ie. ratio represents a fixed
2543  * point number (mult + frac * 2^(-N)).
2544  *
2545  * N equals to kvm_caps.tsc_scaling_ratio_frac_bits.
2546  */
__scale_tsc(u64 ratio,u64 tsc)2547 static inline u64 __scale_tsc(u64 ratio, u64 tsc)
2548 {
2549 	return mul_u64_u64_shr(tsc, ratio, kvm_caps.tsc_scaling_ratio_frac_bits);
2550 }
2551 
kvm_scale_tsc(u64 tsc,u64 ratio)2552 u64 kvm_scale_tsc(u64 tsc, u64 ratio)
2553 {
2554 	u64 _tsc = tsc;
2555 
2556 	if (ratio != kvm_caps.default_tsc_scaling_ratio)
2557 		_tsc = __scale_tsc(ratio, tsc);
2558 
2559 	return _tsc;
2560 }
2561 
kvm_compute_l1_tsc_offset(struct kvm_vcpu * vcpu,u64 target_tsc)2562 static u64 kvm_compute_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc)
2563 {
2564 	u64 tsc;
2565 
2566 	tsc = kvm_scale_tsc(rdtsc(), vcpu->arch.l1_tsc_scaling_ratio);
2567 
2568 	return target_tsc - tsc;
2569 }
2570 
kvm_read_l1_tsc(struct kvm_vcpu * vcpu,u64 host_tsc)2571 u64 kvm_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc)
2572 {
2573 	return vcpu->arch.l1_tsc_offset +
2574 		kvm_scale_tsc(host_tsc, vcpu->arch.l1_tsc_scaling_ratio);
2575 }
2576 EXPORT_SYMBOL_GPL(kvm_read_l1_tsc);
2577 
kvm_calc_nested_tsc_offset(u64 l1_offset,u64 l2_offset,u64 l2_multiplier)2578 u64 kvm_calc_nested_tsc_offset(u64 l1_offset, u64 l2_offset, u64 l2_multiplier)
2579 {
2580 	u64 nested_offset;
2581 
2582 	if (l2_multiplier == kvm_caps.default_tsc_scaling_ratio)
2583 		nested_offset = l1_offset;
2584 	else
2585 		nested_offset = mul_s64_u64_shr((s64) l1_offset, l2_multiplier,
2586 						kvm_caps.tsc_scaling_ratio_frac_bits);
2587 
2588 	nested_offset += l2_offset;
2589 	return nested_offset;
2590 }
2591 EXPORT_SYMBOL_GPL(kvm_calc_nested_tsc_offset);
2592 
kvm_calc_nested_tsc_multiplier(u64 l1_multiplier,u64 l2_multiplier)2593 u64 kvm_calc_nested_tsc_multiplier(u64 l1_multiplier, u64 l2_multiplier)
2594 {
2595 	if (l2_multiplier != kvm_caps.default_tsc_scaling_ratio)
2596 		return mul_u64_u64_shr(l1_multiplier, l2_multiplier,
2597 				       kvm_caps.tsc_scaling_ratio_frac_bits);
2598 
2599 	return l1_multiplier;
2600 }
2601 EXPORT_SYMBOL_GPL(kvm_calc_nested_tsc_multiplier);
2602 
kvm_vcpu_write_tsc_offset(struct kvm_vcpu * vcpu,u64 l1_offset)2603 static void kvm_vcpu_write_tsc_offset(struct kvm_vcpu *vcpu, u64 l1_offset)
2604 {
2605 	trace_kvm_write_tsc_offset(vcpu->vcpu_id,
2606 				   vcpu->arch.l1_tsc_offset,
2607 				   l1_offset);
2608 
2609 	vcpu->arch.l1_tsc_offset = l1_offset;
2610 
2611 	/*
2612 	 * If we are here because L1 chose not to trap WRMSR to TSC then
2613 	 * according to the spec this should set L1's TSC (as opposed to
2614 	 * setting L1's offset for L2).
2615 	 */
2616 	if (is_guest_mode(vcpu))
2617 		vcpu->arch.tsc_offset = kvm_calc_nested_tsc_offset(
2618 			l1_offset,
2619 			static_call(kvm_x86_get_l2_tsc_offset)(vcpu),
2620 			static_call(kvm_x86_get_l2_tsc_multiplier)(vcpu));
2621 	else
2622 		vcpu->arch.tsc_offset = l1_offset;
2623 
2624 	static_call(kvm_x86_write_tsc_offset)(vcpu);
2625 }
2626 
kvm_vcpu_write_tsc_multiplier(struct kvm_vcpu * vcpu,u64 l1_multiplier)2627 static void kvm_vcpu_write_tsc_multiplier(struct kvm_vcpu *vcpu, u64 l1_multiplier)
2628 {
2629 	vcpu->arch.l1_tsc_scaling_ratio = l1_multiplier;
2630 
2631 	/* Userspace is changing the multiplier while L2 is active */
2632 	if (is_guest_mode(vcpu))
2633 		vcpu->arch.tsc_scaling_ratio = kvm_calc_nested_tsc_multiplier(
2634 			l1_multiplier,
2635 			static_call(kvm_x86_get_l2_tsc_multiplier)(vcpu));
2636 	else
2637 		vcpu->arch.tsc_scaling_ratio = l1_multiplier;
2638 
2639 	if (kvm_caps.has_tsc_control)
2640 		static_call(kvm_x86_write_tsc_multiplier)(vcpu);
2641 }
2642 
kvm_check_tsc_unstable(void)2643 static inline bool kvm_check_tsc_unstable(void)
2644 {
2645 #ifdef CONFIG_X86_64
2646 	/*
2647 	 * TSC is marked unstable when we're running on Hyper-V,
2648 	 * 'TSC page' clocksource is good.
2649 	 */
2650 	if (pvclock_gtod_data.clock.vclock_mode == VDSO_CLOCKMODE_HVCLOCK)
2651 		return false;
2652 #endif
2653 	return check_tsc_unstable();
2654 }
2655 
2656 /*
2657  * Infers attempts to synchronize the guest's tsc from host writes. Sets the
2658  * offset for the vcpu and tracks the TSC matching generation that the vcpu
2659  * participates in.
2660  */
__kvm_synchronize_tsc(struct kvm_vcpu * vcpu,u64 offset,u64 tsc,u64 ns,bool matched)2661 static void __kvm_synchronize_tsc(struct kvm_vcpu *vcpu, u64 offset, u64 tsc,
2662 				  u64 ns, bool matched)
2663 {
2664 	struct kvm *kvm = vcpu->kvm;
2665 
2666 	lockdep_assert_held(&kvm->arch.tsc_write_lock);
2667 
2668 	/*
2669 	 * We also track th most recent recorded KHZ, write and time to
2670 	 * allow the matching interval to be extended at each write.
2671 	 */
2672 	kvm->arch.last_tsc_nsec = ns;
2673 	kvm->arch.last_tsc_write = tsc;
2674 	kvm->arch.last_tsc_khz = vcpu->arch.virtual_tsc_khz;
2675 	kvm->arch.last_tsc_offset = offset;
2676 
2677 	vcpu->arch.last_guest_tsc = tsc;
2678 
2679 	kvm_vcpu_write_tsc_offset(vcpu, offset);
2680 
2681 	if (!matched) {
2682 		/*
2683 		 * We split periods of matched TSC writes into generations.
2684 		 * For each generation, we track the original measured
2685 		 * nanosecond time, offset, and write, so if TSCs are in
2686 		 * sync, we can match exact offset, and if not, we can match
2687 		 * exact software computation in compute_guest_tsc()
2688 		 *
2689 		 * These values are tracked in kvm->arch.cur_xxx variables.
2690 		 */
2691 		kvm->arch.cur_tsc_generation++;
2692 		kvm->arch.cur_tsc_nsec = ns;
2693 		kvm->arch.cur_tsc_write = tsc;
2694 		kvm->arch.cur_tsc_offset = offset;
2695 		kvm->arch.nr_vcpus_matched_tsc = 0;
2696 	} else if (vcpu->arch.this_tsc_generation != kvm->arch.cur_tsc_generation) {
2697 		kvm->arch.nr_vcpus_matched_tsc++;
2698 	}
2699 
2700 	/* Keep track of which generation this VCPU has synchronized to */
2701 	vcpu->arch.this_tsc_generation = kvm->arch.cur_tsc_generation;
2702 	vcpu->arch.this_tsc_nsec = kvm->arch.cur_tsc_nsec;
2703 	vcpu->arch.this_tsc_write = kvm->arch.cur_tsc_write;
2704 
2705 	kvm_track_tsc_matching(vcpu, !matched);
2706 }
2707 
kvm_synchronize_tsc(struct kvm_vcpu * vcpu,u64 * user_value)2708 static void kvm_synchronize_tsc(struct kvm_vcpu *vcpu, u64 *user_value)
2709 {
2710 	u64 data = user_value ? *user_value : 0;
2711 	struct kvm *kvm = vcpu->kvm;
2712 	u64 offset, ns, elapsed;
2713 	unsigned long flags;
2714 	bool matched = false;
2715 	bool synchronizing = false;
2716 
2717 	raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags);
2718 	offset = kvm_compute_l1_tsc_offset(vcpu, data);
2719 	ns = get_kvmclock_base_ns();
2720 	elapsed = ns - kvm->arch.last_tsc_nsec;
2721 
2722 	if (vcpu->arch.virtual_tsc_khz) {
2723 		if (data == 0) {
2724 			/*
2725 			 * Force synchronization when creating a vCPU, or when
2726 			 * userspace explicitly writes a zero value.
2727 			 */
2728 			synchronizing = true;
2729 		} else if (kvm->arch.user_set_tsc) {
2730 			u64 tsc_exp = kvm->arch.last_tsc_write +
2731 						nsec_to_cycles(vcpu, elapsed);
2732 			u64 tsc_hz = vcpu->arch.virtual_tsc_khz * 1000LL;
2733 			/*
2734 			 * Here lies UAPI baggage: when a user-initiated TSC write has
2735 			 * a small delta (1 second) of virtual cycle time against the
2736 			 * previously set vCPU, we assume that they were intended to be
2737 			 * in sync and the delta was only due to the racy nature of the
2738 			 * legacy API.
2739 			 *
2740 			 * This trick falls down when restoring a guest which genuinely
2741 			 * has been running for less time than the 1 second of imprecision
2742 			 * which we allow for in the legacy API. In this case, the first
2743 			 * value written by userspace (on any vCPU) should not be subject
2744 			 * to this 'correction' to make it sync up with values that only
2745 			 * come from the kernel's default vCPU creation. Make the 1-second
2746 			 * slop hack only trigger if the user_set_tsc flag is already set.
2747 			 */
2748 			synchronizing = data < tsc_exp + tsc_hz &&
2749 					data + tsc_hz > tsc_exp;
2750 		}
2751 	}
2752 
2753 	if (user_value)
2754 		kvm->arch.user_set_tsc = true;
2755 
2756 	/*
2757 	 * For a reliable TSC, we can match TSC offsets, and for an unstable
2758 	 * TSC, we add elapsed time in this computation.  We could let the
2759 	 * compensation code attempt to catch up if we fall behind, but
2760 	 * it's better to try to match offsets from the beginning.
2761          */
2762 	if (synchronizing &&
2763 	    vcpu->arch.virtual_tsc_khz == kvm->arch.last_tsc_khz) {
2764 		if (!kvm_check_tsc_unstable()) {
2765 			offset = kvm->arch.cur_tsc_offset;
2766 		} else {
2767 			u64 delta = nsec_to_cycles(vcpu, elapsed);
2768 			data += delta;
2769 			offset = kvm_compute_l1_tsc_offset(vcpu, data);
2770 		}
2771 		matched = true;
2772 	}
2773 
2774 	__kvm_synchronize_tsc(vcpu, offset, data, ns, matched);
2775 	raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags);
2776 }
2777 
adjust_tsc_offset_guest(struct kvm_vcpu * vcpu,s64 adjustment)2778 static inline void adjust_tsc_offset_guest(struct kvm_vcpu *vcpu,
2779 					   s64 adjustment)
2780 {
2781 	u64 tsc_offset = vcpu->arch.l1_tsc_offset;
2782 	kvm_vcpu_write_tsc_offset(vcpu, tsc_offset + adjustment);
2783 }
2784 
adjust_tsc_offset_host(struct kvm_vcpu * vcpu,s64 adjustment)2785 static inline void adjust_tsc_offset_host(struct kvm_vcpu *vcpu, s64 adjustment)
2786 {
2787 	if (vcpu->arch.l1_tsc_scaling_ratio != kvm_caps.default_tsc_scaling_ratio)
2788 		WARN_ON(adjustment < 0);
2789 	adjustment = kvm_scale_tsc((u64) adjustment,
2790 				   vcpu->arch.l1_tsc_scaling_ratio);
2791 	adjust_tsc_offset_guest(vcpu, adjustment);
2792 }
2793 
2794 #ifdef CONFIG_X86_64
2795 
read_tsc(void)2796 static u64 read_tsc(void)
2797 {
2798 	u64 ret = (u64)rdtsc_ordered();
2799 	u64 last = pvclock_gtod_data.clock.cycle_last;
2800 
2801 	if (likely(ret >= last))
2802 		return ret;
2803 
2804 	/*
2805 	 * GCC likes to generate cmov here, but this branch is extremely
2806 	 * predictable (it's just a function of time and the likely is
2807 	 * very likely) and there's a data dependence, so force GCC
2808 	 * to generate a branch instead.  I don't barrier() because
2809 	 * we don't actually need a barrier, and if this function
2810 	 * ever gets inlined it will generate worse code.
2811 	 */
2812 	asm volatile ("");
2813 	return last;
2814 }
2815 
vgettsc(struct pvclock_clock * clock,u64 * tsc_timestamp,int * mode)2816 static inline u64 vgettsc(struct pvclock_clock *clock, u64 *tsc_timestamp,
2817 			  int *mode)
2818 {
2819 	u64 tsc_pg_val;
2820 	long v;
2821 
2822 	switch (clock->vclock_mode) {
2823 	case VDSO_CLOCKMODE_HVCLOCK:
2824 		if (hv_read_tsc_page_tsc(hv_get_tsc_page(),
2825 					 tsc_timestamp, &tsc_pg_val)) {
2826 			/* TSC page valid */
2827 			*mode = VDSO_CLOCKMODE_HVCLOCK;
2828 			v = (tsc_pg_val - clock->cycle_last) &
2829 				clock->mask;
2830 		} else {
2831 			/* TSC page invalid */
2832 			*mode = VDSO_CLOCKMODE_NONE;
2833 		}
2834 		break;
2835 	case VDSO_CLOCKMODE_TSC:
2836 		*mode = VDSO_CLOCKMODE_TSC;
2837 		*tsc_timestamp = read_tsc();
2838 		v = (*tsc_timestamp - clock->cycle_last) &
2839 			clock->mask;
2840 		break;
2841 	default:
2842 		*mode = VDSO_CLOCKMODE_NONE;
2843 	}
2844 
2845 	if (*mode == VDSO_CLOCKMODE_NONE)
2846 		*tsc_timestamp = v = 0;
2847 
2848 	return v * clock->mult;
2849 }
2850 
2851 /*
2852  * As with get_kvmclock_base_ns(), this counts from boot time, at the
2853  * frequency of CLOCK_MONOTONIC_RAW (hence adding gtos->offs_boot).
2854  */
do_kvmclock_base(s64 * t,u64 * tsc_timestamp)2855 static int do_kvmclock_base(s64 *t, u64 *tsc_timestamp)
2856 {
2857 	struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
2858 	unsigned long seq;
2859 	int mode;
2860 	u64 ns;
2861 
2862 	do {
2863 		seq = read_seqcount_begin(&gtod->seq);
2864 		ns = gtod->raw_clock.base_cycles;
2865 		ns += vgettsc(&gtod->raw_clock, tsc_timestamp, &mode);
2866 		ns >>= gtod->raw_clock.shift;
2867 		ns += ktime_to_ns(ktime_add(gtod->raw_clock.offset, gtod->offs_boot));
2868 	} while (unlikely(read_seqcount_retry(&gtod->seq, seq)));
2869 	*t = ns;
2870 
2871 	return mode;
2872 }
2873 
2874 /*
2875  * This calculates CLOCK_MONOTONIC at the time of the TSC snapshot, with
2876  * no boot time offset.
2877  */
do_monotonic(s64 * t,u64 * tsc_timestamp)2878 static int do_monotonic(s64 *t, u64 *tsc_timestamp)
2879 {
2880 	struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
2881 	unsigned long seq;
2882 	int mode;
2883 	u64 ns;
2884 
2885 	do {
2886 		seq = read_seqcount_begin(&gtod->seq);
2887 		ns = gtod->clock.base_cycles;
2888 		ns += vgettsc(&gtod->clock, tsc_timestamp, &mode);
2889 		ns >>= gtod->clock.shift;
2890 		ns += ktime_to_ns(gtod->clock.offset);
2891 	} while (unlikely(read_seqcount_retry(&gtod->seq, seq)));
2892 	*t = ns;
2893 
2894 	return mode;
2895 }
2896 
do_realtime(struct timespec64 * ts,u64 * tsc_timestamp)2897 static int do_realtime(struct timespec64 *ts, u64 *tsc_timestamp)
2898 {
2899 	struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
2900 	unsigned long seq;
2901 	int mode;
2902 	u64 ns;
2903 
2904 	do {
2905 		seq = read_seqcount_begin(&gtod->seq);
2906 		ts->tv_sec = gtod->wall_time_sec;
2907 		ns = gtod->clock.base_cycles;
2908 		ns += vgettsc(&gtod->clock, tsc_timestamp, &mode);
2909 		ns >>= gtod->clock.shift;
2910 	} while (unlikely(read_seqcount_retry(&gtod->seq, seq)));
2911 
2912 	ts->tv_sec += __iter_div_u64_rem(ns, NSEC_PER_SEC, &ns);
2913 	ts->tv_nsec = ns;
2914 
2915 	return mode;
2916 }
2917 
2918 /*
2919  * Calculates the kvmclock_base_ns (CLOCK_MONOTONIC_RAW + boot time) and
2920  * reports the TSC value from which it do so. Returns true if host is
2921  * using TSC based clocksource.
2922  */
kvm_get_time_and_clockread(s64 * kernel_ns,u64 * tsc_timestamp)2923 static bool kvm_get_time_and_clockread(s64 *kernel_ns, u64 *tsc_timestamp)
2924 {
2925 	/* checked again under seqlock below */
2926 	if (!gtod_is_based_on_tsc(pvclock_gtod_data.clock.vclock_mode))
2927 		return false;
2928 
2929 	return gtod_is_based_on_tsc(do_kvmclock_base(kernel_ns,
2930 						     tsc_timestamp));
2931 }
2932 
2933 /*
2934  * Calculates CLOCK_MONOTONIC and reports the TSC value from which it did
2935  * so. Returns true if host is using TSC based clocksource.
2936  */
kvm_get_monotonic_and_clockread(s64 * kernel_ns,u64 * tsc_timestamp)2937 bool kvm_get_monotonic_and_clockread(s64 *kernel_ns, u64 *tsc_timestamp)
2938 {
2939 	/* checked again under seqlock below */
2940 	if (!gtod_is_based_on_tsc(pvclock_gtod_data.clock.vclock_mode))
2941 		return false;
2942 
2943 	return gtod_is_based_on_tsc(do_monotonic(kernel_ns,
2944 						 tsc_timestamp));
2945 }
2946 
2947 /*
2948  * Calculates CLOCK_REALTIME and reports the TSC value from which it did
2949  * so. Returns true if host is using TSC based clocksource.
2950  *
2951  * DO NOT USE this for anything related to migration. You want CLOCK_TAI
2952  * for that.
2953  */
kvm_get_walltime_and_clockread(struct timespec64 * ts,u64 * tsc_timestamp)2954 static bool kvm_get_walltime_and_clockread(struct timespec64 *ts,
2955 					   u64 *tsc_timestamp)
2956 {
2957 	/* checked again under seqlock below */
2958 	if (!gtod_is_based_on_tsc(pvclock_gtod_data.clock.vclock_mode))
2959 		return false;
2960 
2961 	return gtod_is_based_on_tsc(do_realtime(ts, tsc_timestamp));
2962 }
2963 #endif
2964 
2965 /*
2966  *
2967  * Assuming a stable TSC across physical CPUS, and a stable TSC
2968  * across virtual CPUs, the following condition is possible.
2969  * Each numbered line represents an event visible to both
2970  * CPUs at the next numbered event.
2971  *
2972  * "timespecX" represents host monotonic time. "tscX" represents
2973  * RDTSC value.
2974  *
2975  * 		VCPU0 on CPU0		|	VCPU1 on CPU1
2976  *
2977  * 1.  read timespec0,tsc0
2978  * 2.					| timespec1 = timespec0 + N
2979  * 					| tsc1 = tsc0 + M
2980  * 3. transition to guest		| transition to guest
2981  * 4. ret0 = timespec0 + (rdtsc - tsc0) |
2982  * 5.				        | ret1 = timespec1 + (rdtsc - tsc1)
2983  * 				        | ret1 = timespec0 + N + (rdtsc - (tsc0 + M))
2984  *
2985  * Since ret0 update is visible to VCPU1 at time 5, to obey monotonicity:
2986  *
2987  * 	- ret0 < ret1
2988  *	- timespec0 + (rdtsc - tsc0) < timespec0 + N + (rdtsc - (tsc0 + M))
2989  *		...
2990  *	- 0 < N - M => M < N
2991  *
2992  * That is, when timespec0 != timespec1, M < N. Unfortunately that is not
2993  * always the case (the difference between two distinct xtime instances
2994  * might be smaller then the difference between corresponding TSC reads,
2995  * when updating guest vcpus pvclock areas).
2996  *
2997  * To avoid that problem, do not allow visibility of distinct
2998  * system_timestamp/tsc_timestamp values simultaneously: use a master
2999  * copy of host monotonic time values. Update that master copy
3000  * in lockstep.
3001  *
3002  * Rely on synchronization of host TSCs and guest TSCs for monotonicity.
3003  *
3004  */
3005 
pvclock_update_vm_gtod_copy(struct kvm * kvm)3006 static void pvclock_update_vm_gtod_copy(struct kvm *kvm)
3007 {
3008 #ifdef CONFIG_X86_64
3009 	struct kvm_arch *ka = &kvm->arch;
3010 	int vclock_mode;
3011 	bool host_tsc_clocksource, vcpus_matched;
3012 
3013 	lockdep_assert_held(&kvm->arch.tsc_write_lock);
3014 	vcpus_matched = (ka->nr_vcpus_matched_tsc + 1 ==
3015 			atomic_read(&kvm->online_vcpus));
3016 
3017 	/*
3018 	 * If the host uses TSC clock, then passthrough TSC as stable
3019 	 * to the guest.
3020 	 */
3021 	host_tsc_clocksource = kvm_get_time_and_clockread(
3022 					&ka->master_kernel_ns,
3023 					&ka->master_cycle_now);
3024 
3025 	ka->use_master_clock = host_tsc_clocksource && vcpus_matched
3026 				&& !ka->backwards_tsc_observed
3027 				&& !ka->boot_vcpu_runs_old_kvmclock;
3028 
3029 	if (ka->use_master_clock)
3030 		atomic_set(&kvm_guest_has_master_clock, 1);
3031 
3032 	vclock_mode = pvclock_gtod_data.clock.vclock_mode;
3033 	trace_kvm_update_master_clock(ka->use_master_clock, vclock_mode,
3034 					vcpus_matched);
3035 #endif
3036 }
3037 
kvm_make_mclock_inprogress_request(struct kvm * kvm)3038 static void kvm_make_mclock_inprogress_request(struct kvm *kvm)
3039 {
3040 	kvm_make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS);
3041 }
3042 
__kvm_start_pvclock_update(struct kvm * kvm)3043 static void __kvm_start_pvclock_update(struct kvm *kvm)
3044 {
3045 	raw_spin_lock_irq(&kvm->arch.tsc_write_lock);
3046 	write_seqcount_begin(&kvm->arch.pvclock_sc);
3047 }
3048 
kvm_start_pvclock_update(struct kvm * kvm)3049 static void kvm_start_pvclock_update(struct kvm *kvm)
3050 {
3051 	kvm_make_mclock_inprogress_request(kvm);
3052 
3053 	/* no guest entries from this point */
3054 	__kvm_start_pvclock_update(kvm);
3055 }
3056 
kvm_end_pvclock_update(struct kvm * kvm)3057 static void kvm_end_pvclock_update(struct kvm *kvm)
3058 {
3059 	struct kvm_arch *ka = &kvm->arch;
3060 	struct kvm_vcpu *vcpu;
3061 	unsigned long i;
3062 
3063 	write_seqcount_end(&ka->pvclock_sc);
3064 	raw_spin_unlock_irq(&ka->tsc_write_lock);
3065 	kvm_for_each_vcpu(i, vcpu, kvm)
3066 		kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
3067 
3068 	/* guest entries allowed */
3069 	kvm_for_each_vcpu(i, vcpu, kvm)
3070 		kvm_clear_request(KVM_REQ_MCLOCK_INPROGRESS, vcpu);
3071 }
3072 
kvm_update_masterclock(struct kvm * kvm)3073 static void kvm_update_masterclock(struct kvm *kvm)
3074 {
3075 	kvm_hv_request_tsc_page_update(kvm);
3076 	kvm_start_pvclock_update(kvm);
3077 	pvclock_update_vm_gtod_copy(kvm);
3078 	kvm_end_pvclock_update(kvm);
3079 }
3080 
3081 /*
3082  * Use the kernel's tsc_khz directly if the TSC is constant, otherwise use KVM's
3083  * per-CPU value (which may be zero if a CPU is going offline).  Note, tsc_khz
3084  * can change during boot even if the TSC is constant, as it's possible for KVM
3085  * to be loaded before TSC calibration completes.  Ideally, KVM would get a
3086  * notification when calibration completes, but practically speaking calibration
3087  * will complete before userspace is alive enough to create VMs.
3088  */
get_cpu_tsc_khz(void)3089 static unsigned long get_cpu_tsc_khz(void)
3090 {
3091 	if (static_cpu_has(X86_FEATURE_CONSTANT_TSC))
3092 		return tsc_khz;
3093 	else
3094 		return __this_cpu_read(cpu_tsc_khz);
3095 }
3096 
3097 /* Called within read_seqcount_begin/retry for kvm->pvclock_sc.  */
__get_kvmclock(struct kvm * kvm,struct kvm_clock_data * data)3098 static void __get_kvmclock(struct kvm *kvm, struct kvm_clock_data *data)
3099 {
3100 	struct kvm_arch *ka = &kvm->arch;
3101 	struct pvclock_vcpu_time_info hv_clock;
3102 
3103 	/* both __this_cpu_read() and rdtsc() should be on the same cpu */
3104 	get_cpu();
3105 
3106 	data->flags = 0;
3107 	if (ka->use_master_clock &&
3108 	    (static_cpu_has(X86_FEATURE_CONSTANT_TSC) || __this_cpu_read(cpu_tsc_khz))) {
3109 #ifdef CONFIG_X86_64
3110 		struct timespec64 ts;
3111 
3112 		if (kvm_get_walltime_and_clockread(&ts, &data->host_tsc)) {
3113 			data->realtime = ts.tv_nsec + NSEC_PER_SEC * ts.tv_sec;
3114 			data->flags |= KVM_CLOCK_REALTIME | KVM_CLOCK_HOST_TSC;
3115 		} else
3116 #endif
3117 		data->host_tsc = rdtsc();
3118 
3119 		data->flags |= KVM_CLOCK_TSC_STABLE;
3120 		hv_clock.tsc_timestamp = ka->master_cycle_now;
3121 		hv_clock.system_time = ka->master_kernel_ns + ka->kvmclock_offset;
3122 		kvm_get_time_scale(NSEC_PER_SEC, get_cpu_tsc_khz() * 1000LL,
3123 				   &hv_clock.tsc_shift,
3124 				   &hv_clock.tsc_to_system_mul);
3125 		data->clock = __pvclock_read_cycles(&hv_clock, data->host_tsc);
3126 	} else {
3127 		data->clock = get_kvmclock_base_ns() + ka->kvmclock_offset;
3128 	}
3129 
3130 	put_cpu();
3131 }
3132 
get_kvmclock(struct kvm * kvm,struct kvm_clock_data * data)3133 static void get_kvmclock(struct kvm *kvm, struct kvm_clock_data *data)
3134 {
3135 	struct kvm_arch *ka = &kvm->arch;
3136 	unsigned seq;
3137 
3138 	do {
3139 		seq = read_seqcount_begin(&ka->pvclock_sc);
3140 		__get_kvmclock(kvm, data);
3141 	} while (read_seqcount_retry(&ka->pvclock_sc, seq));
3142 }
3143 
get_kvmclock_ns(struct kvm * kvm)3144 u64 get_kvmclock_ns(struct kvm *kvm)
3145 {
3146 	struct kvm_clock_data data;
3147 
3148 	get_kvmclock(kvm, &data);
3149 	return data.clock;
3150 }
3151 
kvm_setup_guest_pvclock(struct kvm_vcpu * v,struct gfn_to_pfn_cache * gpc,unsigned int offset,bool force_tsc_unstable)3152 static void kvm_setup_guest_pvclock(struct kvm_vcpu *v,
3153 				    struct gfn_to_pfn_cache *gpc,
3154 				    unsigned int offset,
3155 				    bool force_tsc_unstable)
3156 {
3157 	struct kvm_vcpu_arch *vcpu = &v->arch;
3158 	struct pvclock_vcpu_time_info *guest_hv_clock;
3159 	unsigned long flags;
3160 
3161 	read_lock_irqsave(&gpc->lock, flags);
3162 	while (!kvm_gpc_check(gpc, offset + sizeof(*guest_hv_clock))) {
3163 		read_unlock_irqrestore(&gpc->lock, flags);
3164 
3165 		if (kvm_gpc_refresh(gpc, offset + sizeof(*guest_hv_clock)))
3166 			return;
3167 
3168 		read_lock_irqsave(&gpc->lock, flags);
3169 	}
3170 
3171 	guest_hv_clock = (void *)(gpc->khva + offset);
3172 
3173 	/*
3174 	 * This VCPU is paused, but it's legal for a guest to read another
3175 	 * VCPU's kvmclock, so we really have to follow the specification where
3176 	 * it says that version is odd if data is being modified, and even after
3177 	 * it is consistent.
3178 	 */
3179 
3180 	guest_hv_clock->version = vcpu->hv_clock.version = (guest_hv_clock->version + 1) | 1;
3181 	smp_wmb();
3182 
3183 	/* retain PVCLOCK_GUEST_STOPPED if set in guest copy */
3184 	vcpu->hv_clock.flags |= (guest_hv_clock->flags & PVCLOCK_GUEST_STOPPED);
3185 
3186 	if (vcpu->pvclock_set_guest_stopped_request) {
3187 		vcpu->hv_clock.flags |= PVCLOCK_GUEST_STOPPED;
3188 		vcpu->pvclock_set_guest_stopped_request = false;
3189 	}
3190 
3191 	memcpy(guest_hv_clock, &vcpu->hv_clock, sizeof(*guest_hv_clock));
3192 
3193 	if (force_tsc_unstable)
3194 		guest_hv_clock->flags &= ~PVCLOCK_TSC_STABLE_BIT;
3195 
3196 	smp_wmb();
3197 
3198 	guest_hv_clock->version = ++vcpu->hv_clock.version;
3199 
3200 	kvm_gpc_mark_dirty_in_slot(gpc);
3201 	read_unlock_irqrestore(&gpc->lock, flags);
3202 
3203 	trace_kvm_pvclock_update(v->vcpu_id, &vcpu->hv_clock);
3204 }
3205 
kvm_guest_time_update(struct kvm_vcpu * v)3206 static int kvm_guest_time_update(struct kvm_vcpu *v)
3207 {
3208 	unsigned long flags, tgt_tsc_khz;
3209 	unsigned seq;
3210 	struct kvm_vcpu_arch *vcpu = &v->arch;
3211 	struct kvm_arch *ka = &v->kvm->arch;
3212 	s64 kernel_ns;
3213 	u64 tsc_timestamp, host_tsc;
3214 	u8 pvclock_flags;
3215 	bool use_master_clock;
3216 #ifdef CONFIG_KVM_XEN
3217 	/*
3218 	 * For Xen guests we may need to override PVCLOCK_TSC_STABLE_BIT as unless
3219 	 * explicitly told to use TSC as its clocksource Xen will not set this bit.
3220 	 * This default behaviour led to bugs in some guest kernels which cause
3221 	 * problems if they observe PVCLOCK_TSC_STABLE_BIT in the pvclock flags.
3222 	 */
3223 	bool xen_pvclock_tsc_unstable =
3224 		ka->xen_hvm_config.flags & KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE;
3225 #endif
3226 
3227 	kernel_ns = 0;
3228 	host_tsc = 0;
3229 
3230 	/*
3231 	 * If the host uses TSC clock, then passthrough TSC as stable
3232 	 * to the guest.
3233 	 */
3234 	do {
3235 		seq = read_seqcount_begin(&ka->pvclock_sc);
3236 		use_master_clock = ka->use_master_clock;
3237 		if (use_master_clock) {
3238 			host_tsc = ka->master_cycle_now;
3239 			kernel_ns = ka->master_kernel_ns;
3240 		}
3241 	} while (read_seqcount_retry(&ka->pvclock_sc, seq));
3242 
3243 	/* Keep irq disabled to prevent changes to the clock */
3244 	local_irq_save(flags);
3245 	tgt_tsc_khz = get_cpu_tsc_khz();
3246 	if (unlikely(tgt_tsc_khz == 0)) {
3247 		local_irq_restore(flags);
3248 		kvm_make_request(KVM_REQ_CLOCK_UPDATE, v);
3249 		return 1;
3250 	}
3251 	if (!use_master_clock) {
3252 		host_tsc = rdtsc();
3253 		kernel_ns = get_kvmclock_base_ns();
3254 	}
3255 
3256 	tsc_timestamp = kvm_read_l1_tsc(v, host_tsc);
3257 
3258 	/*
3259 	 * We may have to catch up the TSC to match elapsed wall clock
3260 	 * time for two reasons, even if kvmclock is used.
3261 	 *   1) CPU could have been running below the maximum TSC rate
3262 	 *   2) Broken TSC compensation resets the base at each VCPU
3263 	 *      entry to avoid unknown leaps of TSC even when running
3264 	 *      again on the same CPU.  This may cause apparent elapsed
3265 	 *      time to disappear, and the guest to stand still or run
3266 	 *	very slowly.
3267 	 */
3268 	if (vcpu->tsc_catchup) {
3269 		u64 tsc = compute_guest_tsc(v, kernel_ns);
3270 		if (tsc > tsc_timestamp) {
3271 			adjust_tsc_offset_guest(v, tsc - tsc_timestamp);
3272 			tsc_timestamp = tsc;
3273 		}
3274 	}
3275 
3276 	local_irq_restore(flags);
3277 
3278 	/* With all the info we got, fill in the values */
3279 
3280 	if (kvm_caps.has_tsc_control)
3281 		tgt_tsc_khz = kvm_scale_tsc(tgt_tsc_khz,
3282 					    v->arch.l1_tsc_scaling_ratio);
3283 
3284 	if (unlikely(vcpu->hw_tsc_khz != tgt_tsc_khz)) {
3285 		kvm_get_time_scale(NSEC_PER_SEC, tgt_tsc_khz * 1000LL,
3286 				   &vcpu->hv_clock.tsc_shift,
3287 				   &vcpu->hv_clock.tsc_to_system_mul);
3288 		vcpu->hw_tsc_khz = tgt_tsc_khz;
3289 		kvm_xen_update_tsc_info(v);
3290 	}
3291 
3292 	vcpu->hv_clock.tsc_timestamp = tsc_timestamp;
3293 	vcpu->hv_clock.system_time = kernel_ns + v->kvm->arch.kvmclock_offset;
3294 	vcpu->last_guest_tsc = tsc_timestamp;
3295 
3296 	/* If the host uses TSC clocksource, then it is stable */
3297 	pvclock_flags = 0;
3298 	if (use_master_clock)
3299 		pvclock_flags |= PVCLOCK_TSC_STABLE_BIT;
3300 
3301 	vcpu->hv_clock.flags = pvclock_flags;
3302 
3303 	if (vcpu->pv_time.active)
3304 		kvm_setup_guest_pvclock(v, &vcpu->pv_time, 0, false);
3305 #ifdef CONFIG_KVM_XEN
3306 	if (vcpu->xen.vcpu_info_cache.active)
3307 		kvm_setup_guest_pvclock(v, &vcpu->xen.vcpu_info_cache,
3308 					offsetof(struct compat_vcpu_info, time),
3309 					xen_pvclock_tsc_unstable);
3310 	if (vcpu->xen.vcpu_time_info_cache.active)
3311 		kvm_setup_guest_pvclock(v, &vcpu->xen.vcpu_time_info_cache, 0,
3312 					xen_pvclock_tsc_unstable);
3313 #endif
3314 	kvm_hv_setup_tsc_page(v->kvm, &vcpu->hv_clock);
3315 	return 0;
3316 }
3317 
3318 /*
3319  * The pvclock_wall_clock ABI tells the guest the wall clock time at
3320  * which it started (i.e. its epoch, when its kvmclock was zero).
3321  *
3322  * In fact those clocks are subtly different; wall clock frequency is
3323  * adjusted by NTP and has leap seconds, while the kvmclock is a
3324  * simple function of the TSC without any such adjustment.
3325  *
3326  * Perhaps the ABI should have exposed CLOCK_TAI and a ratio between
3327  * that and kvmclock, but even that would be subject to change over
3328  * time.
3329  *
3330  * Attempt to calculate the epoch at a given moment using the *same*
3331  * TSC reading via kvm_get_walltime_and_clockread() to obtain both
3332  * wallclock and kvmclock times, and subtracting one from the other.
3333  *
3334  * Fall back to using their values at slightly different moments by
3335  * calling ktime_get_real_ns() and get_kvmclock_ns() separately.
3336  */
kvm_get_wall_clock_epoch(struct kvm * kvm)3337 uint64_t kvm_get_wall_clock_epoch(struct kvm *kvm)
3338 {
3339 #ifdef CONFIG_X86_64
3340 	struct pvclock_vcpu_time_info hv_clock;
3341 	struct kvm_arch *ka = &kvm->arch;
3342 	unsigned long seq, local_tsc_khz;
3343 	struct timespec64 ts;
3344 	uint64_t host_tsc;
3345 
3346 	do {
3347 		seq = read_seqcount_begin(&ka->pvclock_sc);
3348 
3349 		local_tsc_khz = 0;
3350 		if (!ka->use_master_clock)
3351 			break;
3352 
3353 		/*
3354 		 * The TSC read and the call to get_cpu_tsc_khz() must happen
3355 		 * on the same CPU.
3356 		 */
3357 		get_cpu();
3358 
3359 		local_tsc_khz = get_cpu_tsc_khz();
3360 
3361 		if (local_tsc_khz &&
3362 		    !kvm_get_walltime_and_clockread(&ts, &host_tsc))
3363 			local_tsc_khz = 0; /* Fall back to old method */
3364 
3365 		put_cpu();
3366 
3367 		/*
3368 		 * These values must be snapshotted within the seqcount loop.
3369 		 * After that, it's just mathematics which can happen on any
3370 		 * CPU at any time.
3371 		 */
3372 		hv_clock.tsc_timestamp = ka->master_cycle_now;
3373 		hv_clock.system_time = ka->master_kernel_ns + ka->kvmclock_offset;
3374 
3375 	} while (read_seqcount_retry(&ka->pvclock_sc, seq));
3376 
3377 	/*
3378 	 * If the conditions were right, and obtaining the wallclock+TSC was
3379 	 * successful, calculate the KVM clock at the corresponding time and
3380 	 * subtract one from the other to get the guest's epoch in nanoseconds
3381 	 * since 1970-01-01.
3382 	 */
3383 	if (local_tsc_khz) {
3384 		kvm_get_time_scale(NSEC_PER_SEC, local_tsc_khz * NSEC_PER_USEC,
3385 				   &hv_clock.tsc_shift,
3386 				   &hv_clock.tsc_to_system_mul);
3387 		return ts.tv_nsec + NSEC_PER_SEC * ts.tv_sec -
3388 			__pvclock_read_cycles(&hv_clock, host_tsc);
3389 	}
3390 #endif
3391 	return ktime_get_real_ns() - get_kvmclock_ns(kvm);
3392 }
3393 
3394 /*
3395  * kvmclock updates which are isolated to a given vcpu, such as
3396  * vcpu->cpu migration, should not allow system_timestamp from
3397  * the rest of the vcpus to remain static. Otherwise ntp frequency
3398  * correction applies to one vcpu's system_timestamp but not
3399  * the others.
3400  *
3401  * So in those cases, request a kvmclock update for all vcpus.
3402  * We need to rate-limit these requests though, as they can
3403  * considerably slow guests that have a large number of vcpus.
3404  * The time for a remote vcpu to update its kvmclock is bound
3405  * by the delay we use to rate-limit the updates.
3406  */
3407 
3408 #define KVMCLOCK_UPDATE_DELAY msecs_to_jiffies(100)
3409 
kvmclock_update_fn(struct work_struct * work)3410 static void kvmclock_update_fn(struct work_struct *work)
3411 {
3412 	unsigned long i;
3413 	struct delayed_work *dwork = to_delayed_work(work);
3414 	struct kvm_arch *ka = container_of(dwork, struct kvm_arch,
3415 					   kvmclock_update_work);
3416 	struct kvm *kvm = container_of(ka, struct kvm, arch);
3417 	struct kvm_vcpu *vcpu;
3418 
3419 	kvm_for_each_vcpu(i, vcpu, kvm) {
3420 		kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
3421 		kvm_vcpu_kick(vcpu);
3422 	}
3423 }
3424 
kvm_gen_kvmclock_update(struct kvm_vcpu * v)3425 static void kvm_gen_kvmclock_update(struct kvm_vcpu *v)
3426 {
3427 	struct kvm *kvm = v->kvm;
3428 
3429 	kvm_make_request(KVM_REQ_CLOCK_UPDATE, v);
3430 	schedule_delayed_work(&kvm->arch.kvmclock_update_work,
3431 					KVMCLOCK_UPDATE_DELAY);
3432 }
3433 
3434 #define KVMCLOCK_SYNC_PERIOD (300 * HZ)
3435 
kvmclock_sync_fn(struct work_struct * work)3436 static void kvmclock_sync_fn(struct work_struct *work)
3437 {
3438 	struct delayed_work *dwork = to_delayed_work(work);
3439 	struct kvm_arch *ka = container_of(dwork, struct kvm_arch,
3440 					   kvmclock_sync_work);
3441 	struct kvm *kvm = container_of(ka, struct kvm, arch);
3442 
3443 	schedule_delayed_work(&kvm->arch.kvmclock_update_work, 0);
3444 	schedule_delayed_work(&kvm->arch.kvmclock_sync_work,
3445 					KVMCLOCK_SYNC_PERIOD);
3446 }
3447 
3448 /* These helpers are safe iff @msr is known to be an MCx bank MSR. */
is_mci_control_msr(u32 msr)3449 static bool is_mci_control_msr(u32 msr)
3450 {
3451 	return (msr & 3) == 0;
3452 }
is_mci_status_msr(u32 msr)3453 static bool is_mci_status_msr(u32 msr)
3454 {
3455 	return (msr & 3) == 1;
3456 }
3457 
3458 /*
3459  * On AMD, HWCR[McStatusWrEn] controls whether setting MCi_STATUS results in #GP.
3460  */
can_set_mci_status(struct kvm_vcpu * vcpu)3461 static bool can_set_mci_status(struct kvm_vcpu *vcpu)
3462 {
3463 	/* McStatusWrEn enabled? */
3464 	if (guest_cpuid_is_amd_compatible(vcpu))
3465 		return !!(vcpu->arch.msr_hwcr & BIT_ULL(18));
3466 
3467 	return false;
3468 }
3469 
set_msr_mce(struct kvm_vcpu * vcpu,struct msr_data * msr_info)3470 static int set_msr_mce(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
3471 {
3472 	u64 mcg_cap = vcpu->arch.mcg_cap;
3473 	unsigned bank_num = mcg_cap & 0xff;
3474 	u32 msr = msr_info->index;
3475 	u64 data = msr_info->data;
3476 	u32 offset, last_msr;
3477 
3478 	switch (msr) {
3479 	case MSR_IA32_MCG_STATUS:
3480 		vcpu->arch.mcg_status = data;
3481 		break;
3482 	case MSR_IA32_MCG_CTL:
3483 		if (!(mcg_cap & MCG_CTL_P) &&
3484 		    (data || !msr_info->host_initiated))
3485 			return 1;
3486 		if (data != 0 && data != ~(u64)0)
3487 			return 1;
3488 		vcpu->arch.mcg_ctl = data;
3489 		break;
3490 	case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1:
3491 		last_msr = MSR_IA32_MCx_CTL2(bank_num) - 1;
3492 		if (msr > last_msr)
3493 			return 1;
3494 
3495 		if (!(mcg_cap & MCG_CMCI_P) && (data || !msr_info->host_initiated))
3496 			return 1;
3497 		/* An attempt to write a 1 to a reserved bit raises #GP */
3498 		if (data & ~(MCI_CTL2_CMCI_EN | MCI_CTL2_CMCI_THRESHOLD_MASK))
3499 			return 1;
3500 		offset = array_index_nospec(msr - MSR_IA32_MC0_CTL2,
3501 					    last_msr + 1 - MSR_IA32_MC0_CTL2);
3502 		vcpu->arch.mci_ctl2_banks[offset] = data;
3503 		break;
3504 	case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1:
3505 		last_msr = MSR_IA32_MCx_CTL(bank_num) - 1;
3506 		if (msr > last_msr)
3507 			return 1;
3508 
3509 		/*
3510 		 * Only 0 or all 1s can be written to IA32_MCi_CTL, all other
3511 		 * values are architecturally undefined.  But, some Linux
3512 		 * kernels clear bit 10 in bank 4 to workaround a BIOS/GART TLB
3513 		 * issue on AMD K8s, allow bit 10 to be clear when setting all
3514 		 * other bits in order to avoid an uncaught #GP in the guest.
3515 		 *
3516 		 * UNIXWARE clears bit 0 of MC1_CTL to ignore correctable,
3517 		 * single-bit ECC data errors.
3518 		 */
3519 		if (is_mci_control_msr(msr) &&
3520 		    data != 0 && (data | (1 << 10) | 1) != ~(u64)0)
3521 			return 1;
3522 
3523 		/*
3524 		 * All CPUs allow writing 0 to MCi_STATUS MSRs to clear the MSR.
3525 		 * AMD-based CPUs allow non-zero values, but if and only if
3526 		 * HWCR[McStatusWrEn] is set.
3527 		 */
3528 		if (!msr_info->host_initiated && is_mci_status_msr(msr) &&
3529 		    data != 0 && !can_set_mci_status(vcpu))
3530 			return 1;
3531 
3532 		offset = array_index_nospec(msr - MSR_IA32_MC0_CTL,
3533 					    last_msr + 1 - MSR_IA32_MC0_CTL);
3534 		vcpu->arch.mce_banks[offset] = data;
3535 		break;
3536 	default:
3537 		return 1;
3538 	}
3539 	return 0;
3540 }
3541 
kvm_pv_async_pf_enabled(struct kvm_vcpu * vcpu)3542 static inline bool kvm_pv_async_pf_enabled(struct kvm_vcpu *vcpu)
3543 {
3544 	u64 mask = KVM_ASYNC_PF_ENABLED | KVM_ASYNC_PF_DELIVERY_AS_INT;
3545 
3546 	return (vcpu->arch.apf.msr_en_val & mask) == mask;
3547 }
3548 
kvm_pv_enable_async_pf(struct kvm_vcpu * vcpu,u64 data)3549 static int kvm_pv_enable_async_pf(struct kvm_vcpu *vcpu, u64 data)
3550 {
3551 	gpa_t gpa = data & ~0x3f;
3552 
3553 	/* Bits 4:5 are reserved, Should be zero */
3554 	if (data & 0x30)
3555 		return 1;
3556 
3557 	if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_VMEXIT) &&
3558 	    (data & KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT))
3559 		return 1;
3560 
3561 	if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT) &&
3562 	    (data & KVM_ASYNC_PF_DELIVERY_AS_INT))
3563 		return 1;
3564 
3565 	if (!lapic_in_kernel(vcpu))
3566 		return data ? 1 : 0;
3567 
3568 	vcpu->arch.apf.msr_en_val = data;
3569 
3570 	if (!kvm_pv_async_pf_enabled(vcpu)) {
3571 		kvm_clear_async_pf_completion_queue(vcpu);
3572 		kvm_async_pf_hash_reset(vcpu);
3573 		return 0;
3574 	}
3575 
3576 	if (kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.apf.data, gpa,
3577 					sizeof(u64)))
3578 		return 1;
3579 
3580 	vcpu->arch.apf.send_user_only = !(data & KVM_ASYNC_PF_SEND_ALWAYS);
3581 	vcpu->arch.apf.delivery_as_pf_vmexit = data & KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT;
3582 
3583 	kvm_async_pf_wakeup_all(vcpu);
3584 
3585 	return 0;
3586 }
3587 
kvm_pv_enable_async_pf_int(struct kvm_vcpu * vcpu,u64 data)3588 static int kvm_pv_enable_async_pf_int(struct kvm_vcpu *vcpu, u64 data)
3589 {
3590 	/* Bits 8-63 are reserved */
3591 	if (data >> 8)
3592 		return 1;
3593 
3594 	if (!lapic_in_kernel(vcpu))
3595 		return 1;
3596 
3597 	vcpu->arch.apf.msr_int_val = data;
3598 
3599 	vcpu->arch.apf.vec = data & KVM_ASYNC_PF_VEC_MASK;
3600 
3601 	return 0;
3602 }
3603 
kvmclock_reset(struct kvm_vcpu * vcpu)3604 static void kvmclock_reset(struct kvm_vcpu *vcpu)
3605 {
3606 	kvm_gpc_deactivate(&vcpu->arch.pv_time);
3607 	vcpu->arch.time = 0;
3608 }
3609 
kvm_vcpu_flush_tlb_all(struct kvm_vcpu * vcpu)3610 static void kvm_vcpu_flush_tlb_all(struct kvm_vcpu *vcpu)
3611 {
3612 	++vcpu->stat.tlb_flush;
3613 	static_call(kvm_x86_flush_tlb_all)(vcpu);
3614 
3615 	/* Flushing all ASIDs flushes the current ASID... */
3616 	kvm_clear_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu);
3617 }
3618 
kvm_vcpu_flush_tlb_guest(struct kvm_vcpu * vcpu)3619 static void kvm_vcpu_flush_tlb_guest(struct kvm_vcpu *vcpu)
3620 {
3621 	++vcpu->stat.tlb_flush;
3622 
3623 	if (!tdp_enabled) {
3624 		/*
3625 		 * A TLB flush on behalf of the guest is equivalent to
3626 		 * INVPCID(all), toggling CR4.PGE, etc., which requires
3627 		 * a forced sync of the shadow page tables.  Ensure all the
3628 		 * roots are synced and the guest TLB in hardware is clean.
3629 		 */
3630 		kvm_mmu_sync_roots(vcpu);
3631 		kvm_mmu_sync_prev_roots(vcpu);
3632 	}
3633 
3634 	static_call(kvm_x86_flush_tlb_guest)(vcpu);
3635 
3636 	/*
3637 	 * Flushing all "guest" TLB is always a superset of Hyper-V's fine
3638 	 * grained flushing.
3639 	 */
3640 	kvm_hv_vcpu_purge_flush_tlb(vcpu);
3641 }
3642 
3643 
kvm_vcpu_flush_tlb_current(struct kvm_vcpu * vcpu)3644 static inline void kvm_vcpu_flush_tlb_current(struct kvm_vcpu *vcpu)
3645 {
3646 	++vcpu->stat.tlb_flush;
3647 	static_call(kvm_x86_flush_tlb_current)(vcpu);
3648 }
3649 
3650 /*
3651  * Service "local" TLB flush requests, which are specific to the current MMU
3652  * context.  In addition to the generic event handling in vcpu_enter_guest(),
3653  * TLB flushes that are targeted at an MMU context also need to be serviced
3654  * prior before nested VM-Enter/VM-Exit.
3655  */
kvm_service_local_tlb_flush_requests(struct kvm_vcpu * vcpu)3656 void kvm_service_local_tlb_flush_requests(struct kvm_vcpu *vcpu)
3657 {
3658 	if (kvm_check_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu))
3659 		kvm_vcpu_flush_tlb_current(vcpu);
3660 
3661 	if (kvm_check_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu))
3662 		kvm_vcpu_flush_tlb_guest(vcpu);
3663 }
3664 EXPORT_SYMBOL_GPL(kvm_service_local_tlb_flush_requests);
3665 
record_steal_time(struct kvm_vcpu * vcpu)3666 static void record_steal_time(struct kvm_vcpu *vcpu)
3667 {
3668 	struct gfn_to_hva_cache *ghc = &vcpu->arch.st.cache;
3669 	struct kvm_steal_time __user *st;
3670 	struct kvm_memslots *slots;
3671 	gpa_t gpa = vcpu->arch.st.msr_val & KVM_STEAL_VALID_BITS;
3672 	u64 steal;
3673 	u32 version;
3674 
3675 	if (kvm_xen_msr_enabled(vcpu->kvm)) {
3676 		kvm_xen_runstate_set_running(vcpu);
3677 		return;
3678 	}
3679 
3680 	if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED))
3681 		return;
3682 
3683 	if (WARN_ON_ONCE(current->mm != vcpu->kvm->mm))
3684 		return;
3685 
3686 	slots = kvm_memslots(vcpu->kvm);
3687 
3688 	if (unlikely(slots->generation != ghc->generation ||
3689 		     gpa != ghc->gpa ||
3690 		     kvm_is_error_hva(ghc->hva) || !ghc->memslot)) {
3691 		/* We rely on the fact that it fits in a single page. */
3692 		BUILD_BUG_ON((sizeof(*st) - 1) & KVM_STEAL_VALID_BITS);
3693 
3694 		if (kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, gpa, sizeof(*st)) ||
3695 		    kvm_is_error_hva(ghc->hva) || !ghc->memslot)
3696 			return;
3697 	}
3698 
3699 	st = (struct kvm_steal_time __user *)ghc->hva;
3700 	/*
3701 	 * Doing a TLB flush here, on the guest's behalf, can avoid
3702 	 * expensive IPIs.
3703 	 */
3704 	if (guest_pv_has(vcpu, KVM_FEATURE_PV_TLB_FLUSH)) {
3705 		u8 st_preempted = 0;
3706 		int err = -EFAULT;
3707 
3708 		if (!user_access_begin(st, sizeof(*st)))
3709 			return;
3710 
3711 		asm volatile("1: xchgb %0, %2\n"
3712 			     "xor %1, %1\n"
3713 			     "2:\n"
3714 			     _ASM_EXTABLE_UA(1b, 2b)
3715 			     : "+q" (st_preempted),
3716 			       "+&r" (err),
3717 			       "+m" (st->preempted));
3718 		if (err)
3719 			goto out;
3720 
3721 		user_access_end();
3722 
3723 		vcpu->arch.st.preempted = 0;
3724 
3725 		trace_kvm_pv_tlb_flush(vcpu->vcpu_id,
3726 				       st_preempted & KVM_VCPU_FLUSH_TLB);
3727 		if (st_preempted & KVM_VCPU_FLUSH_TLB)
3728 			kvm_vcpu_flush_tlb_guest(vcpu);
3729 
3730 		if (!user_access_begin(st, sizeof(*st)))
3731 			goto dirty;
3732 	} else {
3733 		if (!user_access_begin(st, sizeof(*st)))
3734 			return;
3735 
3736 		unsafe_put_user(0, &st->preempted, out);
3737 		vcpu->arch.st.preempted = 0;
3738 	}
3739 
3740 	unsafe_get_user(version, &st->version, out);
3741 	if (version & 1)
3742 		version += 1;  /* first time write, random junk */
3743 
3744 	version += 1;
3745 	unsafe_put_user(version, &st->version, out);
3746 
3747 	smp_wmb();
3748 
3749 	unsafe_get_user(steal, &st->steal, out);
3750 	steal += current->sched_info.run_delay -
3751 		vcpu->arch.st.last_steal;
3752 	vcpu->arch.st.last_steal = current->sched_info.run_delay;
3753 	unsafe_put_user(steal, &st->steal, out);
3754 
3755 	version += 1;
3756 	unsafe_put_user(version, &st->version, out);
3757 
3758  out:
3759 	user_access_end();
3760  dirty:
3761 	mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa));
3762 }
3763 
kvm_is_msr_to_save(u32 msr_index)3764 static bool kvm_is_msr_to_save(u32 msr_index)
3765 {
3766 	unsigned int i;
3767 
3768 	for (i = 0; i < num_msrs_to_save; i++) {
3769 		if (msrs_to_save[i] == msr_index)
3770 			return true;
3771 	}
3772 
3773 	return false;
3774 }
3775 
kvm_set_msr_common(struct kvm_vcpu * vcpu,struct msr_data * msr_info)3776 int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
3777 {
3778 	u32 msr = msr_info->index;
3779 	u64 data = msr_info->data;
3780 
3781 	if (msr && msr == vcpu->kvm->arch.xen_hvm_config.msr)
3782 		return kvm_xen_write_hypercall_page(vcpu, data);
3783 
3784 	switch (msr) {
3785 	case MSR_AMD64_NB_CFG:
3786 	case MSR_IA32_UCODE_WRITE:
3787 	case MSR_VM_HSAVE_PA:
3788 	case MSR_AMD64_PATCH_LOADER:
3789 	case MSR_AMD64_BU_CFG2:
3790 	case MSR_AMD64_DC_CFG:
3791 	case MSR_AMD64_TW_CFG:
3792 	case MSR_F15H_EX_CFG:
3793 		break;
3794 
3795 	case MSR_IA32_UCODE_REV:
3796 		if (msr_info->host_initiated)
3797 			vcpu->arch.microcode_version = data;
3798 		break;
3799 	case MSR_IA32_ARCH_CAPABILITIES:
3800 		if (!msr_info->host_initiated)
3801 			return 1;
3802 		vcpu->arch.arch_capabilities = data;
3803 		break;
3804 	case MSR_IA32_PERF_CAPABILITIES:
3805 		if (!msr_info->host_initiated)
3806 			return 1;
3807 		if (data & ~kvm_caps.supported_perf_cap)
3808 			return 1;
3809 
3810 		/*
3811 		 * Note, this is not just a performance optimization!  KVM
3812 		 * disallows changing feature MSRs after the vCPU has run; PMU
3813 		 * refresh will bug the VM if called after the vCPU has run.
3814 		 */
3815 		if (vcpu->arch.perf_capabilities == data)
3816 			break;
3817 
3818 		vcpu->arch.perf_capabilities = data;
3819 		kvm_pmu_refresh(vcpu);
3820 		break;
3821 	case MSR_IA32_PRED_CMD: {
3822 		u64 reserved_bits = ~(PRED_CMD_IBPB | PRED_CMD_SBPB);
3823 
3824 		if (!msr_info->host_initiated) {
3825 			if ((!guest_has_pred_cmd_msr(vcpu)))
3826 				return 1;
3827 
3828 			if (!guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL) &&
3829 			    !guest_cpuid_has(vcpu, X86_FEATURE_AMD_IBPB))
3830 				reserved_bits |= PRED_CMD_IBPB;
3831 
3832 			if (!guest_cpuid_has(vcpu, X86_FEATURE_SBPB))
3833 				reserved_bits |= PRED_CMD_SBPB;
3834 		}
3835 
3836 		if (!boot_cpu_has(X86_FEATURE_IBPB))
3837 			reserved_bits |= PRED_CMD_IBPB;
3838 
3839 		if (!boot_cpu_has(X86_FEATURE_SBPB))
3840 			reserved_bits |= PRED_CMD_SBPB;
3841 
3842 		if (data & reserved_bits)
3843 			return 1;
3844 
3845 		if (!data)
3846 			break;
3847 
3848 		wrmsrl(MSR_IA32_PRED_CMD, data);
3849 		break;
3850 	}
3851 	case MSR_IA32_FLUSH_CMD:
3852 		if (!msr_info->host_initiated &&
3853 		    !guest_cpuid_has(vcpu, X86_FEATURE_FLUSH_L1D))
3854 			return 1;
3855 
3856 		if (!boot_cpu_has(X86_FEATURE_FLUSH_L1D) || (data & ~L1D_FLUSH))
3857 			return 1;
3858 		if (!data)
3859 			break;
3860 
3861 		wrmsrl(MSR_IA32_FLUSH_CMD, L1D_FLUSH);
3862 		break;
3863 	case MSR_EFER:
3864 		return set_efer(vcpu, msr_info);
3865 	case MSR_K7_HWCR:
3866 		data &= ~(u64)0x40;	/* ignore flush filter disable */
3867 		data &= ~(u64)0x100;	/* ignore ignne emulation enable */
3868 		data &= ~(u64)0x8;	/* ignore TLB cache disable */
3869 
3870 		/*
3871 		 * Allow McStatusWrEn and TscFreqSel. (Linux guests from v3.2
3872 		 * through at least v6.6 whine if TscFreqSel is clear,
3873 		 * depending on F/M/S.
3874 		 */
3875 		if (data & ~(BIT_ULL(18) | BIT_ULL(24))) {
3876 			kvm_pr_unimpl_wrmsr(vcpu, msr, data);
3877 			return 1;
3878 		}
3879 		vcpu->arch.msr_hwcr = data;
3880 		break;
3881 	case MSR_FAM10H_MMIO_CONF_BASE:
3882 		if (data != 0) {
3883 			kvm_pr_unimpl_wrmsr(vcpu, msr, data);
3884 			return 1;
3885 		}
3886 		break;
3887 	case MSR_IA32_CR_PAT:
3888 		if (!kvm_pat_valid(data))
3889 			return 1;
3890 
3891 		vcpu->arch.pat = data;
3892 		break;
3893 	case MTRRphysBase_MSR(0) ... MSR_MTRRfix4K_F8000:
3894 	case MSR_MTRRdefType:
3895 		return kvm_mtrr_set_msr(vcpu, msr, data);
3896 	case MSR_IA32_APICBASE:
3897 		return kvm_set_apic_base(vcpu, msr_info);
3898 	case APIC_BASE_MSR ... APIC_BASE_MSR + 0xff:
3899 		return kvm_x2apic_msr_write(vcpu, msr, data);
3900 	case MSR_IA32_TSC_DEADLINE:
3901 		kvm_set_lapic_tscdeadline_msr(vcpu, data);
3902 		break;
3903 	case MSR_IA32_TSC_ADJUST:
3904 		if (guest_cpuid_has(vcpu, X86_FEATURE_TSC_ADJUST)) {
3905 			if (!msr_info->host_initiated) {
3906 				s64 adj = data - vcpu->arch.ia32_tsc_adjust_msr;
3907 				adjust_tsc_offset_guest(vcpu, adj);
3908 				/* Before back to guest, tsc_timestamp must be adjusted
3909 				 * as well, otherwise guest's percpu pvclock time could jump.
3910 				 */
3911 				kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
3912 			}
3913 			vcpu->arch.ia32_tsc_adjust_msr = data;
3914 		}
3915 		break;
3916 	case MSR_IA32_MISC_ENABLE: {
3917 		u64 old_val = vcpu->arch.ia32_misc_enable_msr;
3918 
3919 		if (!msr_info->host_initiated) {
3920 			/* RO bits */
3921 			if ((old_val ^ data) & MSR_IA32_MISC_ENABLE_PMU_RO_MASK)
3922 				return 1;
3923 
3924 			/* R bits, i.e. writes are ignored, but don't fault. */
3925 			data = data & ~MSR_IA32_MISC_ENABLE_EMON;
3926 			data |= old_val & MSR_IA32_MISC_ENABLE_EMON;
3927 		}
3928 
3929 		if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT) &&
3930 		    ((old_val ^ data)  & MSR_IA32_MISC_ENABLE_MWAIT)) {
3931 			if (!guest_cpuid_has(vcpu, X86_FEATURE_XMM3))
3932 				return 1;
3933 			vcpu->arch.ia32_misc_enable_msr = data;
3934 			kvm_update_cpuid_runtime(vcpu);
3935 		} else {
3936 			vcpu->arch.ia32_misc_enable_msr = data;
3937 		}
3938 		break;
3939 	}
3940 	case MSR_IA32_SMBASE:
3941 		if (!IS_ENABLED(CONFIG_KVM_SMM) || !msr_info->host_initiated)
3942 			return 1;
3943 		vcpu->arch.smbase = data;
3944 		break;
3945 	case MSR_IA32_POWER_CTL:
3946 		vcpu->arch.msr_ia32_power_ctl = data;
3947 		break;
3948 	case MSR_IA32_TSC:
3949 		if (msr_info->host_initiated) {
3950 			kvm_synchronize_tsc(vcpu, &data);
3951 		} else {
3952 			u64 adj = kvm_compute_l1_tsc_offset(vcpu, data) - vcpu->arch.l1_tsc_offset;
3953 			adjust_tsc_offset_guest(vcpu, adj);
3954 			vcpu->arch.ia32_tsc_adjust_msr += adj;
3955 		}
3956 		break;
3957 	case MSR_IA32_XSS:
3958 		if (!msr_info->host_initiated &&
3959 		    !guest_cpuid_has(vcpu, X86_FEATURE_XSAVES))
3960 			return 1;
3961 		/*
3962 		 * KVM supports exposing PT to the guest, but does not support
3963 		 * IA32_XSS[bit 8]. Guests have to use RDMSR/WRMSR rather than
3964 		 * XSAVES/XRSTORS to save/restore PT MSRs.
3965 		 */
3966 		if (data & ~kvm_caps.supported_xss)
3967 			return 1;
3968 		vcpu->arch.ia32_xss = data;
3969 		kvm_update_cpuid_runtime(vcpu);
3970 		break;
3971 	case MSR_SMI_COUNT:
3972 		if (!msr_info->host_initiated)
3973 			return 1;
3974 		vcpu->arch.smi_count = data;
3975 		break;
3976 	case MSR_KVM_WALL_CLOCK_NEW:
3977 		if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
3978 			return 1;
3979 
3980 		vcpu->kvm->arch.wall_clock = data;
3981 		kvm_write_wall_clock(vcpu->kvm, data, 0);
3982 		break;
3983 	case MSR_KVM_WALL_CLOCK:
3984 		if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
3985 			return 1;
3986 
3987 		vcpu->kvm->arch.wall_clock = data;
3988 		kvm_write_wall_clock(vcpu->kvm, data, 0);
3989 		break;
3990 	case MSR_KVM_SYSTEM_TIME_NEW:
3991 		if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
3992 			return 1;
3993 
3994 		kvm_write_system_time(vcpu, data, false, msr_info->host_initiated);
3995 		break;
3996 	case MSR_KVM_SYSTEM_TIME:
3997 		if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
3998 			return 1;
3999 
4000 		kvm_write_system_time(vcpu, data, true,  msr_info->host_initiated);
4001 		break;
4002 	case MSR_KVM_ASYNC_PF_EN:
4003 		if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF))
4004 			return 1;
4005 
4006 		if (kvm_pv_enable_async_pf(vcpu, data))
4007 			return 1;
4008 		break;
4009 	case MSR_KVM_ASYNC_PF_INT:
4010 		if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT))
4011 			return 1;
4012 
4013 		if (kvm_pv_enable_async_pf_int(vcpu, data))
4014 			return 1;
4015 		break;
4016 	case MSR_KVM_ASYNC_PF_ACK:
4017 		if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT))
4018 			return 1;
4019 		if (data & 0x1) {
4020 			vcpu->arch.apf.pageready_pending = false;
4021 			kvm_check_async_pf_completion(vcpu);
4022 		}
4023 		break;
4024 	case MSR_KVM_STEAL_TIME:
4025 		if (!guest_pv_has(vcpu, KVM_FEATURE_STEAL_TIME))
4026 			return 1;
4027 
4028 		if (unlikely(!sched_info_on()))
4029 			return 1;
4030 
4031 		if (data & KVM_STEAL_RESERVED_MASK)
4032 			return 1;
4033 
4034 		vcpu->arch.st.msr_val = data;
4035 
4036 		if (!(data & KVM_MSR_ENABLED))
4037 			break;
4038 
4039 		kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu);
4040 
4041 		break;
4042 	case MSR_KVM_PV_EOI_EN:
4043 		if (!guest_pv_has(vcpu, KVM_FEATURE_PV_EOI))
4044 			return 1;
4045 
4046 		if (kvm_lapic_set_pv_eoi(vcpu, data, sizeof(u8)))
4047 			return 1;
4048 		break;
4049 
4050 	case MSR_KVM_POLL_CONTROL:
4051 		if (!guest_pv_has(vcpu, KVM_FEATURE_POLL_CONTROL))
4052 			return 1;
4053 
4054 		/* only enable bit supported */
4055 		if (data & (-1ULL << 1))
4056 			return 1;
4057 
4058 		vcpu->arch.msr_kvm_poll_control = data;
4059 		break;
4060 
4061 	case MSR_IA32_MCG_CTL:
4062 	case MSR_IA32_MCG_STATUS:
4063 	case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1:
4064 	case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1:
4065 		return set_msr_mce(vcpu, msr_info);
4066 
4067 	case MSR_K7_PERFCTR0 ... MSR_K7_PERFCTR3:
4068 	case MSR_P6_PERFCTR0 ... MSR_P6_PERFCTR1:
4069 	case MSR_K7_EVNTSEL0 ... MSR_K7_EVNTSEL3:
4070 	case MSR_P6_EVNTSEL0 ... MSR_P6_EVNTSEL1:
4071 		if (kvm_pmu_is_valid_msr(vcpu, msr))
4072 			return kvm_pmu_set_msr(vcpu, msr_info);
4073 
4074 		if (data)
4075 			kvm_pr_unimpl_wrmsr(vcpu, msr, data);
4076 		break;
4077 	case MSR_K7_CLK_CTL:
4078 		/*
4079 		 * Ignore all writes to this no longer documented MSR.
4080 		 * Writes are only relevant for old K7 processors,
4081 		 * all pre-dating SVM, but a recommended workaround from
4082 		 * AMD for these chips. It is possible to specify the
4083 		 * affected processor models on the command line, hence
4084 		 * the need to ignore the workaround.
4085 		 */
4086 		break;
4087 #ifdef CONFIG_KVM_HYPERV
4088 	case HV_X64_MSR_GUEST_OS_ID ... HV_X64_MSR_SINT15:
4089 	case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
4090 	case HV_X64_MSR_SYNDBG_OPTIONS:
4091 	case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
4092 	case HV_X64_MSR_CRASH_CTL:
4093 	case HV_X64_MSR_STIMER0_CONFIG ... HV_X64_MSR_STIMER3_COUNT:
4094 	case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
4095 	case HV_X64_MSR_TSC_EMULATION_CONTROL:
4096 	case HV_X64_MSR_TSC_EMULATION_STATUS:
4097 	case HV_X64_MSR_TSC_INVARIANT_CONTROL:
4098 		return kvm_hv_set_msr_common(vcpu, msr, data,
4099 					     msr_info->host_initiated);
4100 #endif
4101 	case MSR_IA32_BBL_CR_CTL3:
4102 		/* Drop writes to this legacy MSR -- see rdmsr
4103 		 * counterpart for further detail.
4104 		 */
4105 		kvm_pr_unimpl_wrmsr(vcpu, msr, data);
4106 		break;
4107 	case MSR_AMD64_OSVW_ID_LENGTH:
4108 		if (!guest_cpuid_has(vcpu, X86_FEATURE_OSVW))
4109 			return 1;
4110 		vcpu->arch.osvw.length = data;
4111 		break;
4112 	case MSR_AMD64_OSVW_STATUS:
4113 		if (!guest_cpuid_has(vcpu, X86_FEATURE_OSVW))
4114 			return 1;
4115 		vcpu->arch.osvw.status = data;
4116 		break;
4117 	case MSR_PLATFORM_INFO:
4118 		if (!msr_info->host_initiated ||
4119 		    (!(data & MSR_PLATFORM_INFO_CPUID_FAULT) &&
4120 		     cpuid_fault_enabled(vcpu)))
4121 			return 1;
4122 		vcpu->arch.msr_platform_info = data;
4123 		break;
4124 	case MSR_MISC_FEATURES_ENABLES:
4125 		if (data & ~MSR_MISC_FEATURES_ENABLES_CPUID_FAULT ||
4126 		    (data & MSR_MISC_FEATURES_ENABLES_CPUID_FAULT &&
4127 		     !supports_cpuid_fault(vcpu)))
4128 			return 1;
4129 		vcpu->arch.msr_misc_features_enables = data;
4130 		break;
4131 #ifdef CONFIG_X86_64
4132 	case MSR_IA32_XFD:
4133 		if (!msr_info->host_initiated &&
4134 		    !guest_cpuid_has(vcpu, X86_FEATURE_XFD))
4135 			return 1;
4136 
4137 		if (data & ~kvm_guest_supported_xfd(vcpu))
4138 			return 1;
4139 
4140 		fpu_update_guest_xfd(&vcpu->arch.guest_fpu, data);
4141 		break;
4142 	case MSR_IA32_XFD_ERR:
4143 		if (!msr_info->host_initiated &&
4144 		    !guest_cpuid_has(vcpu, X86_FEATURE_XFD))
4145 			return 1;
4146 
4147 		if (data & ~kvm_guest_supported_xfd(vcpu))
4148 			return 1;
4149 
4150 		vcpu->arch.guest_fpu.xfd_err = data;
4151 		break;
4152 #endif
4153 	default:
4154 		if (kvm_pmu_is_valid_msr(vcpu, msr))
4155 			return kvm_pmu_set_msr(vcpu, msr_info);
4156 
4157 		/*
4158 		 * Userspace is allowed to write '0' to MSRs that KVM reports
4159 		 * as to-be-saved, even if an MSRs isn't fully supported.
4160 		 */
4161 		if (msr_info->host_initiated && !data &&
4162 		    kvm_is_msr_to_save(msr))
4163 			break;
4164 
4165 		return KVM_MSR_RET_INVALID;
4166 	}
4167 	return 0;
4168 }
4169 EXPORT_SYMBOL_GPL(kvm_set_msr_common);
4170 
get_msr_mce(struct kvm_vcpu * vcpu,u32 msr,u64 * pdata,bool host)4171 static int get_msr_mce(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host)
4172 {
4173 	u64 data;
4174 	u64 mcg_cap = vcpu->arch.mcg_cap;
4175 	unsigned bank_num = mcg_cap & 0xff;
4176 	u32 offset, last_msr;
4177 
4178 	switch (msr) {
4179 	case MSR_IA32_P5_MC_ADDR:
4180 	case MSR_IA32_P5_MC_TYPE:
4181 		data = 0;
4182 		break;
4183 	case MSR_IA32_MCG_CAP:
4184 		data = vcpu->arch.mcg_cap;
4185 		break;
4186 	case MSR_IA32_MCG_CTL:
4187 		if (!(mcg_cap & MCG_CTL_P) && !host)
4188 			return 1;
4189 		data = vcpu->arch.mcg_ctl;
4190 		break;
4191 	case MSR_IA32_MCG_STATUS:
4192 		data = vcpu->arch.mcg_status;
4193 		break;
4194 	case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1:
4195 		last_msr = MSR_IA32_MCx_CTL2(bank_num) - 1;
4196 		if (msr > last_msr)
4197 			return 1;
4198 
4199 		if (!(mcg_cap & MCG_CMCI_P) && !host)
4200 			return 1;
4201 		offset = array_index_nospec(msr - MSR_IA32_MC0_CTL2,
4202 					    last_msr + 1 - MSR_IA32_MC0_CTL2);
4203 		data = vcpu->arch.mci_ctl2_banks[offset];
4204 		break;
4205 	case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1:
4206 		last_msr = MSR_IA32_MCx_CTL(bank_num) - 1;
4207 		if (msr > last_msr)
4208 			return 1;
4209 
4210 		offset = array_index_nospec(msr - MSR_IA32_MC0_CTL,
4211 					    last_msr + 1 - MSR_IA32_MC0_CTL);
4212 		data = vcpu->arch.mce_banks[offset];
4213 		break;
4214 	default:
4215 		return 1;
4216 	}
4217 	*pdata = data;
4218 	return 0;
4219 }
4220 
kvm_get_msr_common(struct kvm_vcpu * vcpu,struct msr_data * msr_info)4221 int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
4222 {
4223 	switch (msr_info->index) {
4224 	case MSR_IA32_PLATFORM_ID:
4225 	case MSR_IA32_EBL_CR_POWERON:
4226 	case MSR_IA32_LASTBRANCHFROMIP:
4227 	case MSR_IA32_LASTBRANCHTOIP:
4228 	case MSR_IA32_LASTINTFROMIP:
4229 	case MSR_IA32_LASTINTTOIP:
4230 	case MSR_AMD64_SYSCFG:
4231 	case MSR_K8_TSEG_ADDR:
4232 	case MSR_K8_TSEG_MASK:
4233 	case MSR_VM_HSAVE_PA:
4234 	case MSR_K8_INT_PENDING_MSG:
4235 	case MSR_AMD64_NB_CFG:
4236 	case MSR_FAM10H_MMIO_CONF_BASE:
4237 	case MSR_AMD64_BU_CFG2:
4238 	case MSR_IA32_PERF_CTL:
4239 	case MSR_AMD64_DC_CFG:
4240 	case MSR_AMD64_TW_CFG:
4241 	case MSR_F15H_EX_CFG:
4242 	/*
4243 	 * Intel Sandy Bridge CPUs must support the RAPL (running average power
4244 	 * limit) MSRs. Just return 0, as we do not want to expose the host
4245 	 * data here. Do not conditionalize this on CPUID, as KVM does not do
4246 	 * so for existing CPU-specific MSRs.
4247 	 */
4248 	case MSR_RAPL_POWER_UNIT:
4249 	case MSR_PP0_ENERGY_STATUS:	/* Power plane 0 (core) */
4250 	case MSR_PP1_ENERGY_STATUS:	/* Power plane 1 (graphics uncore) */
4251 	case MSR_PKG_ENERGY_STATUS:	/* Total package */
4252 	case MSR_DRAM_ENERGY_STATUS:	/* DRAM controller */
4253 		msr_info->data = 0;
4254 		break;
4255 	case MSR_K7_EVNTSEL0 ... MSR_K7_EVNTSEL3:
4256 	case MSR_K7_PERFCTR0 ... MSR_K7_PERFCTR3:
4257 	case MSR_P6_PERFCTR0 ... MSR_P6_PERFCTR1:
4258 	case MSR_P6_EVNTSEL0 ... MSR_P6_EVNTSEL1:
4259 		if (kvm_pmu_is_valid_msr(vcpu, msr_info->index))
4260 			return kvm_pmu_get_msr(vcpu, msr_info);
4261 		msr_info->data = 0;
4262 		break;
4263 	case MSR_IA32_UCODE_REV:
4264 		msr_info->data = vcpu->arch.microcode_version;
4265 		break;
4266 	case MSR_IA32_ARCH_CAPABILITIES:
4267 		if (!msr_info->host_initiated &&
4268 		    !guest_cpuid_has(vcpu, X86_FEATURE_ARCH_CAPABILITIES))
4269 			return 1;
4270 		msr_info->data = vcpu->arch.arch_capabilities;
4271 		break;
4272 	case MSR_IA32_PERF_CAPABILITIES:
4273 		if (!msr_info->host_initiated &&
4274 		    !guest_cpuid_has(vcpu, X86_FEATURE_PDCM))
4275 			return 1;
4276 		msr_info->data = vcpu->arch.perf_capabilities;
4277 		break;
4278 	case MSR_IA32_POWER_CTL:
4279 		msr_info->data = vcpu->arch.msr_ia32_power_ctl;
4280 		break;
4281 	case MSR_IA32_TSC: {
4282 		/*
4283 		 * Intel SDM states that MSR_IA32_TSC read adds the TSC offset
4284 		 * even when not intercepted. AMD manual doesn't explicitly
4285 		 * state this but appears to behave the same.
4286 		 *
4287 		 * On userspace reads and writes, however, we unconditionally
4288 		 * return L1's TSC value to ensure backwards-compatible
4289 		 * behavior for migration.
4290 		 */
4291 		u64 offset, ratio;
4292 
4293 		if (msr_info->host_initiated) {
4294 			offset = vcpu->arch.l1_tsc_offset;
4295 			ratio = vcpu->arch.l1_tsc_scaling_ratio;
4296 		} else {
4297 			offset = vcpu->arch.tsc_offset;
4298 			ratio = vcpu->arch.tsc_scaling_ratio;
4299 		}
4300 
4301 		msr_info->data = kvm_scale_tsc(rdtsc(), ratio) + offset;
4302 		break;
4303 	}
4304 	case MSR_IA32_CR_PAT:
4305 		msr_info->data = vcpu->arch.pat;
4306 		break;
4307 	case MSR_MTRRcap:
4308 	case MTRRphysBase_MSR(0) ... MSR_MTRRfix4K_F8000:
4309 	case MSR_MTRRdefType:
4310 		return kvm_mtrr_get_msr(vcpu, msr_info->index, &msr_info->data);
4311 	case 0xcd: /* fsb frequency */
4312 		msr_info->data = 3;
4313 		break;
4314 		/*
4315 		 * MSR_EBC_FREQUENCY_ID
4316 		 * Conservative value valid for even the basic CPU models.
4317 		 * Models 0,1: 000 in bits 23:21 indicating a bus speed of
4318 		 * 100MHz, model 2 000 in bits 18:16 indicating 100MHz,
4319 		 * and 266MHz for model 3, or 4. Set Core Clock
4320 		 * Frequency to System Bus Frequency Ratio to 1 (bits
4321 		 * 31:24) even though these are only valid for CPU
4322 		 * models > 2, however guests may end up dividing or
4323 		 * multiplying by zero otherwise.
4324 		 */
4325 	case MSR_EBC_FREQUENCY_ID:
4326 		msr_info->data = 1 << 24;
4327 		break;
4328 	case MSR_IA32_APICBASE:
4329 		msr_info->data = kvm_get_apic_base(vcpu);
4330 		break;
4331 	case APIC_BASE_MSR ... APIC_BASE_MSR + 0xff:
4332 		return kvm_x2apic_msr_read(vcpu, msr_info->index, &msr_info->data);
4333 	case MSR_IA32_TSC_DEADLINE:
4334 		msr_info->data = kvm_get_lapic_tscdeadline_msr(vcpu);
4335 		break;
4336 	case MSR_IA32_TSC_ADJUST:
4337 		msr_info->data = (u64)vcpu->arch.ia32_tsc_adjust_msr;
4338 		break;
4339 	case MSR_IA32_MISC_ENABLE:
4340 		msr_info->data = vcpu->arch.ia32_misc_enable_msr;
4341 		break;
4342 	case MSR_IA32_SMBASE:
4343 		if (!IS_ENABLED(CONFIG_KVM_SMM) || !msr_info->host_initiated)
4344 			return 1;
4345 		msr_info->data = vcpu->arch.smbase;
4346 		break;
4347 	case MSR_SMI_COUNT:
4348 		msr_info->data = vcpu->arch.smi_count;
4349 		break;
4350 	case MSR_IA32_PERF_STATUS:
4351 		/* TSC increment by tick */
4352 		msr_info->data = 1000ULL;
4353 		/* CPU multiplier */
4354 		msr_info->data |= (((uint64_t)4ULL) << 40);
4355 		break;
4356 	case MSR_EFER:
4357 		msr_info->data = vcpu->arch.efer;
4358 		break;
4359 	case MSR_KVM_WALL_CLOCK:
4360 		if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
4361 			return 1;
4362 
4363 		msr_info->data = vcpu->kvm->arch.wall_clock;
4364 		break;
4365 	case MSR_KVM_WALL_CLOCK_NEW:
4366 		if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
4367 			return 1;
4368 
4369 		msr_info->data = vcpu->kvm->arch.wall_clock;
4370 		break;
4371 	case MSR_KVM_SYSTEM_TIME:
4372 		if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE))
4373 			return 1;
4374 
4375 		msr_info->data = vcpu->arch.time;
4376 		break;
4377 	case MSR_KVM_SYSTEM_TIME_NEW:
4378 		if (!guest_pv_has(vcpu, KVM_FEATURE_CLOCKSOURCE2))
4379 			return 1;
4380 
4381 		msr_info->data = vcpu->arch.time;
4382 		break;
4383 	case MSR_KVM_ASYNC_PF_EN:
4384 		if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF))
4385 			return 1;
4386 
4387 		msr_info->data = vcpu->arch.apf.msr_en_val;
4388 		break;
4389 	case MSR_KVM_ASYNC_PF_INT:
4390 		if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT))
4391 			return 1;
4392 
4393 		msr_info->data = vcpu->arch.apf.msr_int_val;
4394 		break;
4395 	case MSR_KVM_ASYNC_PF_ACK:
4396 		if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT))
4397 			return 1;
4398 
4399 		msr_info->data = 0;
4400 		break;
4401 	case MSR_KVM_STEAL_TIME:
4402 		if (!guest_pv_has(vcpu, KVM_FEATURE_STEAL_TIME))
4403 			return 1;
4404 
4405 		msr_info->data = vcpu->arch.st.msr_val;
4406 		break;
4407 	case MSR_KVM_PV_EOI_EN:
4408 		if (!guest_pv_has(vcpu, KVM_FEATURE_PV_EOI))
4409 			return 1;
4410 
4411 		msr_info->data = vcpu->arch.pv_eoi.msr_val;
4412 		break;
4413 	case MSR_KVM_POLL_CONTROL:
4414 		if (!guest_pv_has(vcpu, KVM_FEATURE_POLL_CONTROL))
4415 			return 1;
4416 
4417 		msr_info->data = vcpu->arch.msr_kvm_poll_control;
4418 		break;
4419 	case MSR_IA32_P5_MC_ADDR:
4420 	case MSR_IA32_P5_MC_TYPE:
4421 	case MSR_IA32_MCG_CAP:
4422 	case MSR_IA32_MCG_CTL:
4423 	case MSR_IA32_MCG_STATUS:
4424 	case MSR_IA32_MC0_CTL ... MSR_IA32_MCx_CTL(KVM_MAX_MCE_BANKS) - 1:
4425 	case MSR_IA32_MC0_CTL2 ... MSR_IA32_MCx_CTL2(KVM_MAX_MCE_BANKS) - 1:
4426 		return get_msr_mce(vcpu, msr_info->index, &msr_info->data,
4427 				   msr_info->host_initiated);
4428 	case MSR_IA32_XSS:
4429 		if (!msr_info->host_initiated &&
4430 		    !guest_cpuid_has(vcpu, X86_FEATURE_XSAVES))
4431 			return 1;
4432 		msr_info->data = vcpu->arch.ia32_xss;
4433 		break;
4434 	case MSR_K7_CLK_CTL:
4435 		/*
4436 		 * Provide expected ramp-up count for K7. All other
4437 		 * are set to zero, indicating minimum divisors for
4438 		 * every field.
4439 		 *
4440 		 * This prevents guest kernels on AMD host with CPU
4441 		 * type 6, model 8 and higher from exploding due to
4442 		 * the rdmsr failing.
4443 		 */
4444 		msr_info->data = 0x20000000;
4445 		break;
4446 #ifdef CONFIG_KVM_HYPERV
4447 	case HV_X64_MSR_GUEST_OS_ID ... HV_X64_MSR_SINT15:
4448 	case HV_X64_MSR_SYNDBG_CONTROL ... HV_X64_MSR_SYNDBG_PENDING_BUFFER:
4449 	case HV_X64_MSR_SYNDBG_OPTIONS:
4450 	case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4:
4451 	case HV_X64_MSR_CRASH_CTL:
4452 	case HV_X64_MSR_STIMER0_CONFIG ... HV_X64_MSR_STIMER3_COUNT:
4453 	case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
4454 	case HV_X64_MSR_TSC_EMULATION_CONTROL:
4455 	case HV_X64_MSR_TSC_EMULATION_STATUS:
4456 	case HV_X64_MSR_TSC_INVARIANT_CONTROL:
4457 		return kvm_hv_get_msr_common(vcpu,
4458 					     msr_info->index, &msr_info->data,
4459 					     msr_info->host_initiated);
4460 #endif
4461 	case MSR_IA32_BBL_CR_CTL3:
4462 		/* This legacy MSR exists but isn't fully documented in current
4463 		 * silicon.  It is however accessed by winxp in very narrow
4464 		 * scenarios where it sets bit #19, itself documented as
4465 		 * a "reserved" bit.  Best effort attempt to source coherent
4466 		 * read data here should the balance of the register be
4467 		 * interpreted by the guest:
4468 		 *
4469 		 * L2 cache control register 3: 64GB range, 256KB size,
4470 		 * enabled, latency 0x1, configured
4471 		 */
4472 		msr_info->data = 0xbe702111;
4473 		break;
4474 	case MSR_AMD64_OSVW_ID_LENGTH:
4475 		if (!guest_cpuid_has(vcpu, X86_FEATURE_OSVW))
4476 			return 1;
4477 		msr_info->data = vcpu->arch.osvw.length;
4478 		break;
4479 	case MSR_AMD64_OSVW_STATUS:
4480 		if (!guest_cpuid_has(vcpu, X86_FEATURE_OSVW))
4481 			return 1;
4482 		msr_info->data = vcpu->arch.osvw.status;
4483 		break;
4484 	case MSR_PLATFORM_INFO:
4485 		if (!msr_info->host_initiated &&
4486 		    !vcpu->kvm->arch.guest_can_read_msr_platform_info)
4487 			return 1;
4488 		msr_info->data = vcpu->arch.msr_platform_info;
4489 		break;
4490 	case MSR_MISC_FEATURES_ENABLES:
4491 		msr_info->data = vcpu->arch.msr_misc_features_enables;
4492 		break;
4493 	case MSR_K7_HWCR:
4494 		msr_info->data = vcpu->arch.msr_hwcr;
4495 		break;
4496 #ifdef CONFIG_X86_64
4497 	case MSR_IA32_XFD:
4498 		if (!msr_info->host_initiated &&
4499 		    !guest_cpuid_has(vcpu, X86_FEATURE_XFD))
4500 			return 1;
4501 
4502 		msr_info->data = vcpu->arch.guest_fpu.fpstate->xfd;
4503 		break;
4504 	case MSR_IA32_XFD_ERR:
4505 		if (!msr_info->host_initiated &&
4506 		    !guest_cpuid_has(vcpu, X86_FEATURE_XFD))
4507 			return 1;
4508 
4509 		msr_info->data = vcpu->arch.guest_fpu.xfd_err;
4510 		break;
4511 #endif
4512 	default:
4513 		if (kvm_pmu_is_valid_msr(vcpu, msr_info->index))
4514 			return kvm_pmu_get_msr(vcpu, msr_info);
4515 
4516 		/*
4517 		 * Userspace is allowed to read MSRs that KVM reports as
4518 		 * to-be-saved, even if an MSR isn't fully supported.
4519 		 */
4520 		if (msr_info->host_initiated &&
4521 		    kvm_is_msr_to_save(msr_info->index)) {
4522 			msr_info->data = 0;
4523 			break;
4524 		}
4525 
4526 		return KVM_MSR_RET_INVALID;
4527 	}
4528 	return 0;
4529 }
4530 EXPORT_SYMBOL_GPL(kvm_get_msr_common);
4531 
4532 /*
4533  * Read or write a bunch of msrs. All parameters are kernel addresses.
4534  *
4535  * @return number of msrs set successfully.
4536  */
__msr_io(struct kvm_vcpu * vcpu,struct kvm_msrs * msrs,struct kvm_msr_entry * entries,int (* do_msr)(struct kvm_vcpu * vcpu,unsigned index,u64 * data))4537 static int __msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs *msrs,
4538 		    struct kvm_msr_entry *entries,
4539 		    int (*do_msr)(struct kvm_vcpu *vcpu,
4540 				  unsigned index, u64 *data))
4541 {
4542 	int i;
4543 
4544 	for (i = 0; i < msrs->nmsrs; ++i)
4545 		if (do_msr(vcpu, entries[i].index, &entries[i].data))
4546 			break;
4547 
4548 	return i;
4549 }
4550 
4551 /*
4552  * Read or write a bunch of msrs. Parameters are user addresses.
4553  *
4554  * @return number of msrs set successfully.
4555  */
msr_io(struct kvm_vcpu * vcpu,struct kvm_msrs __user * user_msrs,int (* do_msr)(struct kvm_vcpu * vcpu,unsigned index,u64 * data),int writeback)4556 static int msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs __user *user_msrs,
4557 		  int (*do_msr)(struct kvm_vcpu *vcpu,
4558 				unsigned index, u64 *data),
4559 		  int writeback)
4560 {
4561 	struct kvm_msrs msrs;
4562 	struct kvm_msr_entry *entries;
4563 	unsigned size;
4564 	int r;
4565 
4566 	r = -EFAULT;
4567 	if (copy_from_user(&msrs, user_msrs, sizeof(msrs)))
4568 		goto out;
4569 
4570 	r = -E2BIG;
4571 	if (msrs.nmsrs >= MAX_IO_MSRS)
4572 		goto out;
4573 
4574 	size = sizeof(struct kvm_msr_entry) * msrs.nmsrs;
4575 	entries = memdup_user(user_msrs->entries, size);
4576 	if (IS_ERR(entries)) {
4577 		r = PTR_ERR(entries);
4578 		goto out;
4579 	}
4580 
4581 	r = __msr_io(vcpu, &msrs, entries, do_msr);
4582 
4583 	if (writeback && copy_to_user(user_msrs->entries, entries, size))
4584 		r = -EFAULT;
4585 
4586 	kfree(entries);
4587 out:
4588 	return r;
4589 }
4590 
kvm_can_mwait_in_guest(void)4591 static inline bool kvm_can_mwait_in_guest(void)
4592 {
4593 	return boot_cpu_has(X86_FEATURE_MWAIT) &&
4594 		!boot_cpu_has_bug(X86_BUG_MONITOR) &&
4595 		boot_cpu_has(X86_FEATURE_ARAT);
4596 }
4597 
4598 #ifdef CONFIG_KVM_HYPERV
kvm_ioctl_get_supported_hv_cpuid(struct kvm_vcpu * vcpu,struct kvm_cpuid2 __user * cpuid_arg)4599 static int kvm_ioctl_get_supported_hv_cpuid(struct kvm_vcpu *vcpu,
4600 					    struct kvm_cpuid2 __user *cpuid_arg)
4601 {
4602 	struct kvm_cpuid2 cpuid;
4603 	int r;
4604 
4605 	r = -EFAULT;
4606 	if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
4607 		return r;
4608 
4609 	r = kvm_get_hv_cpuid(vcpu, &cpuid, cpuid_arg->entries);
4610 	if (r)
4611 		return r;
4612 
4613 	r = -EFAULT;
4614 	if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid)))
4615 		return r;
4616 
4617 	return 0;
4618 }
4619 #endif
4620 
kvm_is_vm_type_supported(unsigned long type)4621 static bool kvm_is_vm_type_supported(unsigned long type)
4622 {
4623 	return type < 32 && (kvm_caps.supported_vm_types & BIT(type));
4624 }
4625 
kvm_vm_ioctl_check_extension(struct kvm * kvm,long ext)4626 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
4627 {
4628 	int r = 0;
4629 
4630 	switch (ext) {
4631 	case KVM_CAP_IRQCHIP:
4632 	case KVM_CAP_HLT:
4633 	case KVM_CAP_MMU_SHADOW_CACHE_CONTROL:
4634 	case KVM_CAP_SET_TSS_ADDR:
4635 	case KVM_CAP_EXT_CPUID:
4636 	case KVM_CAP_EXT_EMUL_CPUID:
4637 	case KVM_CAP_CLOCKSOURCE:
4638 	case KVM_CAP_PIT:
4639 	case KVM_CAP_NOP_IO_DELAY:
4640 	case KVM_CAP_MP_STATE:
4641 	case KVM_CAP_SYNC_MMU:
4642 	case KVM_CAP_USER_NMI:
4643 	case KVM_CAP_REINJECT_CONTROL:
4644 	case KVM_CAP_IRQ_INJECT_STATUS:
4645 	case KVM_CAP_IOEVENTFD:
4646 	case KVM_CAP_IOEVENTFD_NO_LENGTH:
4647 	case KVM_CAP_PIT2:
4648 	case KVM_CAP_PIT_STATE2:
4649 	case KVM_CAP_SET_IDENTITY_MAP_ADDR:
4650 	case KVM_CAP_VCPU_EVENTS:
4651 #ifdef CONFIG_KVM_HYPERV
4652 	case KVM_CAP_HYPERV:
4653 	case KVM_CAP_HYPERV_VAPIC:
4654 	case KVM_CAP_HYPERV_SPIN:
4655 	case KVM_CAP_HYPERV_TIME:
4656 	case KVM_CAP_HYPERV_SYNIC:
4657 	case KVM_CAP_HYPERV_SYNIC2:
4658 	case KVM_CAP_HYPERV_VP_INDEX:
4659 	case KVM_CAP_HYPERV_EVENTFD:
4660 	case KVM_CAP_HYPERV_TLBFLUSH:
4661 	case KVM_CAP_HYPERV_SEND_IPI:
4662 	case KVM_CAP_HYPERV_CPUID:
4663 	case KVM_CAP_HYPERV_ENFORCE_CPUID:
4664 	case KVM_CAP_SYS_HYPERV_CPUID:
4665 #endif
4666 	case KVM_CAP_PCI_SEGMENT:
4667 	case KVM_CAP_DEBUGREGS:
4668 	case KVM_CAP_X86_ROBUST_SINGLESTEP:
4669 	case KVM_CAP_XSAVE:
4670 	case KVM_CAP_ASYNC_PF:
4671 	case KVM_CAP_ASYNC_PF_INT:
4672 	case KVM_CAP_GET_TSC_KHZ:
4673 	case KVM_CAP_KVMCLOCK_CTRL:
4674 	case KVM_CAP_READONLY_MEM:
4675 	case KVM_CAP_IOAPIC_POLARITY_IGNORED:
4676 	case KVM_CAP_TSC_DEADLINE_TIMER:
4677 	case KVM_CAP_DISABLE_QUIRKS:
4678 	case KVM_CAP_SET_BOOT_CPU_ID:
4679  	case KVM_CAP_SPLIT_IRQCHIP:
4680 	case KVM_CAP_IMMEDIATE_EXIT:
4681 	case KVM_CAP_PMU_EVENT_FILTER:
4682 	case KVM_CAP_PMU_EVENT_MASKED_EVENTS:
4683 	case KVM_CAP_GET_MSR_FEATURES:
4684 	case KVM_CAP_MSR_PLATFORM_INFO:
4685 	case KVM_CAP_EXCEPTION_PAYLOAD:
4686 	case KVM_CAP_X86_TRIPLE_FAULT_EVENT:
4687 	case KVM_CAP_SET_GUEST_DEBUG:
4688 	case KVM_CAP_LAST_CPU:
4689 	case KVM_CAP_X86_USER_SPACE_MSR:
4690 	case KVM_CAP_X86_MSR_FILTER:
4691 	case KVM_CAP_ENFORCE_PV_FEATURE_CPUID:
4692 #ifdef CONFIG_X86_SGX_KVM
4693 	case KVM_CAP_SGX_ATTRIBUTE:
4694 #endif
4695 	case KVM_CAP_VM_COPY_ENC_CONTEXT_FROM:
4696 	case KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM:
4697 	case KVM_CAP_SREGS2:
4698 	case KVM_CAP_EXIT_ON_EMULATION_FAILURE:
4699 	case KVM_CAP_VCPU_ATTRIBUTES:
4700 	case KVM_CAP_SYS_ATTRIBUTES:
4701 	case KVM_CAP_VAPIC:
4702 	case KVM_CAP_ENABLE_CAP:
4703 	case KVM_CAP_VM_DISABLE_NX_HUGE_PAGES:
4704 	case KVM_CAP_IRQFD_RESAMPLE:
4705 	case KVM_CAP_MEMORY_FAULT_INFO:
4706 		r = 1;
4707 		break;
4708 	case KVM_CAP_EXIT_HYPERCALL:
4709 		r = KVM_EXIT_HYPERCALL_VALID_MASK;
4710 		break;
4711 	case KVM_CAP_SET_GUEST_DEBUG2:
4712 		return KVM_GUESTDBG_VALID_MASK;
4713 #ifdef CONFIG_KVM_XEN
4714 	case KVM_CAP_XEN_HVM:
4715 		r = KVM_XEN_HVM_CONFIG_HYPERCALL_MSR |
4716 		    KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL |
4717 		    KVM_XEN_HVM_CONFIG_SHARED_INFO |
4718 		    KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL |
4719 		    KVM_XEN_HVM_CONFIG_EVTCHN_SEND |
4720 		    KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE |
4721 		    KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA;
4722 		if (sched_info_on())
4723 			r |= KVM_XEN_HVM_CONFIG_RUNSTATE |
4724 			     KVM_XEN_HVM_CONFIG_RUNSTATE_UPDATE_FLAG;
4725 		break;
4726 #endif
4727 	case KVM_CAP_SYNC_REGS:
4728 		r = KVM_SYNC_X86_VALID_FIELDS;
4729 		break;
4730 	case KVM_CAP_ADJUST_CLOCK:
4731 		r = KVM_CLOCK_VALID_FLAGS;
4732 		break;
4733 	case KVM_CAP_X86_DISABLE_EXITS:
4734 		r = KVM_X86_DISABLE_EXITS_PAUSE;
4735 
4736 		if (!mitigate_smt_rsb) {
4737 			r |= KVM_X86_DISABLE_EXITS_HLT |
4738 			     KVM_X86_DISABLE_EXITS_CSTATE;
4739 
4740 			if (kvm_can_mwait_in_guest())
4741 				r |= KVM_X86_DISABLE_EXITS_MWAIT;
4742 		}
4743 		break;
4744 	case KVM_CAP_X86_SMM:
4745 		if (!IS_ENABLED(CONFIG_KVM_SMM))
4746 			break;
4747 
4748 		/* SMBASE is usually relocated above 1M on modern chipsets,
4749 		 * and SMM handlers might indeed rely on 4G segment limits,
4750 		 * so do not report SMM to be available if real mode is
4751 		 * emulated via vm86 mode.  Still, do not go to great lengths
4752 		 * to avoid userspace's usage of the feature, because it is a
4753 		 * fringe case that is not enabled except via specific settings
4754 		 * of the module parameters.
4755 		 */
4756 		r = static_call(kvm_x86_has_emulated_msr)(kvm, MSR_IA32_SMBASE);
4757 		break;
4758 	case KVM_CAP_NR_VCPUS:
4759 		r = min_t(unsigned int, num_online_cpus(), KVM_MAX_VCPUS);
4760 		break;
4761 	case KVM_CAP_MAX_VCPUS:
4762 		r = KVM_MAX_VCPUS;
4763 		break;
4764 	case KVM_CAP_MAX_VCPU_ID:
4765 		r = KVM_MAX_VCPU_IDS;
4766 		break;
4767 	case KVM_CAP_PV_MMU:	/* obsolete */
4768 		r = 0;
4769 		break;
4770 	case KVM_CAP_MCE:
4771 		r = KVM_MAX_MCE_BANKS;
4772 		break;
4773 	case KVM_CAP_XCRS:
4774 		r = boot_cpu_has(X86_FEATURE_XSAVE);
4775 		break;
4776 	case KVM_CAP_TSC_CONTROL:
4777 	case KVM_CAP_VM_TSC_CONTROL:
4778 		r = kvm_caps.has_tsc_control;
4779 		break;
4780 	case KVM_CAP_X2APIC_API:
4781 		r = KVM_X2APIC_API_VALID_FLAGS;
4782 		break;
4783 	case KVM_CAP_NESTED_STATE:
4784 		r = kvm_x86_ops.nested_ops->get_state ?
4785 			kvm_x86_ops.nested_ops->get_state(NULL, NULL, 0) : 0;
4786 		break;
4787 #ifdef CONFIG_KVM_HYPERV
4788 	case KVM_CAP_HYPERV_DIRECT_TLBFLUSH:
4789 		r = kvm_x86_ops.enable_l2_tlb_flush != NULL;
4790 		break;
4791 	case KVM_CAP_HYPERV_ENLIGHTENED_VMCS:
4792 		r = kvm_x86_ops.nested_ops->enable_evmcs != NULL;
4793 		break;
4794 #endif
4795 	case KVM_CAP_SMALLER_MAXPHYADDR:
4796 		r = (int) allow_smaller_maxphyaddr;
4797 		break;
4798 	case KVM_CAP_STEAL_TIME:
4799 		r = sched_info_on();
4800 		break;
4801 	case KVM_CAP_X86_BUS_LOCK_EXIT:
4802 		if (kvm_caps.has_bus_lock_exit)
4803 			r = KVM_BUS_LOCK_DETECTION_OFF |
4804 			    KVM_BUS_LOCK_DETECTION_EXIT;
4805 		else
4806 			r = 0;
4807 		break;
4808 	case KVM_CAP_XSAVE2: {
4809 		r = xstate_required_size(kvm_get_filtered_xcr0(), false);
4810 		if (r < sizeof(struct kvm_xsave))
4811 			r = sizeof(struct kvm_xsave);
4812 		break;
4813 	}
4814 	case KVM_CAP_PMU_CAPABILITY:
4815 		r = enable_pmu ? KVM_CAP_PMU_VALID_MASK : 0;
4816 		break;
4817 	case KVM_CAP_DISABLE_QUIRKS2:
4818 		r = KVM_X86_VALID_QUIRKS;
4819 		break;
4820 	case KVM_CAP_X86_NOTIFY_VMEXIT:
4821 		r = kvm_caps.has_notify_vmexit;
4822 		break;
4823 	case KVM_CAP_VM_TYPES:
4824 		r = kvm_caps.supported_vm_types;
4825 		break;
4826 	default:
4827 		break;
4828 	}
4829 	return r;
4830 }
4831 
__kvm_x86_dev_get_attr(struct kvm_device_attr * attr,u64 * val)4832 static int __kvm_x86_dev_get_attr(struct kvm_device_attr *attr, u64 *val)
4833 {
4834 	if (attr->group) {
4835 		if (kvm_x86_ops.dev_get_attr)
4836 			return static_call(kvm_x86_dev_get_attr)(attr->group, attr->attr, val);
4837 		return -ENXIO;
4838 	}
4839 
4840 	switch (attr->attr) {
4841 	case KVM_X86_XCOMP_GUEST_SUPP:
4842 		*val = kvm_caps.supported_xcr0;
4843 		return 0;
4844 	default:
4845 		return -ENXIO;
4846 	}
4847 }
4848 
kvm_x86_dev_get_attr(struct kvm_device_attr * attr)4849 static int kvm_x86_dev_get_attr(struct kvm_device_attr *attr)
4850 {
4851 	u64 __user *uaddr = u64_to_user_ptr(attr->addr);
4852 	int r;
4853 	u64 val;
4854 
4855 	r = __kvm_x86_dev_get_attr(attr, &val);
4856 	if (r < 0)
4857 		return r;
4858 
4859 	if (put_user(val, uaddr))
4860 		return -EFAULT;
4861 
4862 	return 0;
4863 }
4864 
kvm_x86_dev_has_attr(struct kvm_device_attr * attr)4865 static int kvm_x86_dev_has_attr(struct kvm_device_attr *attr)
4866 {
4867 	u64 val;
4868 
4869 	return __kvm_x86_dev_get_attr(attr, &val);
4870 }
4871 
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)4872 long kvm_arch_dev_ioctl(struct file *filp,
4873 			unsigned int ioctl, unsigned long arg)
4874 {
4875 	void __user *argp = (void __user *)arg;
4876 	long r;
4877 
4878 	switch (ioctl) {
4879 	case KVM_GET_MSR_INDEX_LIST: {
4880 		struct kvm_msr_list __user *user_msr_list = argp;
4881 		struct kvm_msr_list msr_list;
4882 		unsigned n;
4883 
4884 		r = -EFAULT;
4885 		if (copy_from_user(&msr_list, user_msr_list, sizeof(msr_list)))
4886 			goto out;
4887 		n = msr_list.nmsrs;
4888 		msr_list.nmsrs = num_msrs_to_save + num_emulated_msrs;
4889 		if (copy_to_user(user_msr_list, &msr_list, sizeof(msr_list)))
4890 			goto out;
4891 		r = -E2BIG;
4892 		if (n < msr_list.nmsrs)
4893 			goto out;
4894 		r = -EFAULT;
4895 		if (copy_to_user(user_msr_list->indices, &msrs_to_save,
4896 				 num_msrs_to_save * sizeof(u32)))
4897 			goto out;
4898 		if (copy_to_user(user_msr_list->indices + num_msrs_to_save,
4899 				 &emulated_msrs,
4900 				 num_emulated_msrs * sizeof(u32)))
4901 			goto out;
4902 		r = 0;
4903 		break;
4904 	}
4905 	case KVM_GET_SUPPORTED_CPUID:
4906 	case KVM_GET_EMULATED_CPUID: {
4907 		struct kvm_cpuid2 __user *cpuid_arg = argp;
4908 		struct kvm_cpuid2 cpuid;
4909 
4910 		r = -EFAULT;
4911 		if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
4912 			goto out;
4913 
4914 		r = kvm_dev_ioctl_get_cpuid(&cpuid, cpuid_arg->entries,
4915 					    ioctl);
4916 		if (r)
4917 			goto out;
4918 
4919 		r = -EFAULT;
4920 		if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid)))
4921 			goto out;
4922 		r = 0;
4923 		break;
4924 	}
4925 	case KVM_X86_GET_MCE_CAP_SUPPORTED:
4926 		r = -EFAULT;
4927 		if (copy_to_user(argp, &kvm_caps.supported_mce_cap,
4928 				 sizeof(kvm_caps.supported_mce_cap)))
4929 			goto out;
4930 		r = 0;
4931 		break;
4932 	case KVM_GET_MSR_FEATURE_INDEX_LIST: {
4933 		struct kvm_msr_list __user *user_msr_list = argp;
4934 		struct kvm_msr_list msr_list;
4935 		unsigned int n;
4936 
4937 		r = -EFAULT;
4938 		if (copy_from_user(&msr_list, user_msr_list, sizeof(msr_list)))
4939 			goto out;
4940 		n = msr_list.nmsrs;
4941 		msr_list.nmsrs = num_msr_based_features;
4942 		if (copy_to_user(user_msr_list, &msr_list, sizeof(msr_list)))
4943 			goto out;
4944 		r = -E2BIG;
4945 		if (n < msr_list.nmsrs)
4946 			goto out;
4947 		r = -EFAULT;
4948 		if (copy_to_user(user_msr_list->indices, &msr_based_features,
4949 				 num_msr_based_features * sizeof(u32)))
4950 			goto out;
4951 		r = 0;
4952 		break;
4953 	}
4954 	case KVM_GET_MSRS:
4955 		r = msr_io(NULL, argp, do_get_msr_feature, 1);
4956 		break;
4957 #ifdef CONFIG_KVM_HYPERV
4958 	case KVM_GET_SUPPORTED_HV_CPUID:
4959 		r = kvm_ioctl_get_supported_hv_cpuid(NULL, argp);
4960 		break;
4961 #endif
4962 	case KVM_GET_DEVICE_ATTR: {
4963 		struct kvm_device_attr attr;
4964 		r = -EFAULT;
4965 		if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
4966 			break;
4967 		r = kvm_x86_dev_get_attr(&attr);
4968 		break;
4969 	}
4970 	case KVM_HAS_DEVICE_ATTR: {
4971 		struct kvm_device_attr attr;
4972 		r = -EFAULT;
4973 		if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
4974 			break;
4975 		r = kvm_x86_dev_has_attr(&attr);
4976 		break;
4977 	}
4978 	default:
4979 		r = -EINVAL;
4980 		break;
4981 	}
4982 out:
4983 	return r;
4984 }
4985 
wbinvd_ipi(void * garbage)4986 static void wbinvd_ipi(void *garbage)
4987 {
4988 	wbinvd();
4989 }
4990 
need_emulate_wbinvd(struct kvm_vcpu * vcpu)4991 static bool need_emulate_wbinvd(struct kvm_vcpu *vcpu)
4992 {
4993 	return kvm_arch_has_noncoherent_dma(vcpu->kvm);
4994 }
4995 
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)4996 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
4997 {
4998 	/* Address WBINVD may be executed by guest */
4999 	if (need_emulate_wbinvd(vcpu)) {
5000 		if (static_call(kvm_x86_has_wbinvd_exit)())
5001 			cpumask_set_cpu(cpu, vcpu->arch.wbinvd_dirty_mask);
5002 		else if (vcpu->cpu != -1 && vcpu->cpu != cpu)
5003 			smp_call_function_single(vcpu->cpu,
5004 					wbinvd_ipi, NULL, 1);
5005 	}
5006 
5007 	static_call(kvm_x86_vcpu_load)(vcpu, cpu);
5008 
5009 	/* Save host pkru register if supported */
5010 	vcpu->arch.host_pkru = read_pkru();
5011 
5012 	/* Apply any externally detected TSC adjustments (due to suspend) */
5013 	if (unlikely(vcpu->arch.tsc_offset_adjustment)) {
5014 		adjust_tsc_offset_host(vcpu, vcpu->arch.tsc_offset_adjustment);
5015 		vcpu->arch.tsc_offset_adjustment = 0;
5016 		kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
5017 	}
5018 
5019 	if (unlikely(vcpu->cpu != cpu) || kvm_check_tsc_unstable()) {
5020 		s64 tsc_delta = !vcpu->arch.last_host_tsc ? 0 :
5021 				rdtsc() - vcpu->arch.last_host_tsc;
5022 		if (tsc_delta < 0)
5023 			mark_tsc_unstable("KVM discovered backwards TSC");
5024 
5025 		if (kvm_check_tsc_unstable()) {
5026 			u64 offset = kvm_compute_l1_tsc_offset(vcpu,
5027 						vcpu->arch.last_guest_tsc);
5028 			kvm_vcpu_write_tsc_offset(vcpu, offset);
5029 			vcpu->arch.tsc_catchup = 1;
5030 		}
5031 
5032 		if (kvm_lapic_hv_timer_in_use(vcpu))
5033 			kvm_lapic_restart_hv_timer(vcpu);
5034 
5035 		/*
5036 		 * On a host with synchronized TSC, there is no need to update
5037 		 * kvmclock on vcpu->cpu migration
5038 		 */
5039 		if (!vcpu->kvm->arch.use_master_clock || vcpu->cpu == -1)
5040 			kvm_make_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu);
5041 		if (vcpu->cpu != cpu)
5042 			kvm_make_request(KVM_REQ_MIGRATE_TIMER, vcpu);
5043 		vcpu->cpu = cpu;
5044 	}
5045 
5046 	kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu);
5047 }
5048 
kvm_steal_time_set_preempted(struct kvm_vcpu * vcpu)5049 static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu)
5050 {
5051 	struct gfn_to_hva_cache *ghc = &vcpu->arch.st.cache;
5052 	struct kvm_steal_time __user *st;
5053 	struct kvm_memslots *slots;
5054 	static const u8 preempted = KVM_VCPU_PREEMPTED;
5055 	gpa_t gpa = vcpu->arch.st.msr_val & KVM_STEAL_VALID_BITS;
5056 
5057 	/*
5058 	 * The vCPU can be marked preempted if and only if the VM-Exit was on
5059 	 * an instruction boundary and will not trigger guest emulation of any
5060 	 * kind (see vcpu_run).  Vendor specific code controls (conservatively)
5061 	 * when this is true, for example allowing the vCPU to be marked
5062 	 * preempted if and only if the VM-Exit was due to a host interrupt.
5063 	 */
5064 	if (!vcpu->arch.at_instruction_boundary) {
5065 		vcpu->stat.preemption_other++;
5066 		return;
5067 	}
5068 
5069 	vcpu->stat.preemption_reported++;
5070 	if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED))
5071 		return;
5072 
5073 	if (vcpu->arch.st.preempted)
5074 		return;
5075 
5076 	/* This happens on process exit */
5077 	if (unlikely(current->mm != vcpu->kvm->mm))
5078 		return;
5079 
5080 	slots = kvm_memslots(vcpu->kvm);
5081 
5082 	if (unlikely(slots->generation != ghc->generation ||
5083 		     gpa != ghc->gpa ||
5084 		     kvm_is_error_hva(ghc->hva) || !ghc->memslot))
5085 		return;
5086 
5087 	st = (struct kvm_steal_time __user *)ghc->hva;
5088 	BUILD_BUG_ON(sizeof(st->preempted) != sizeof(preempted));
5089 
5090 	if (!copy_to_user_nofault(&st->preempted, &preempted, sizeof(preempted)))
5091 		vcpu->arch.st.preempted = KVM_VCPU_PREEMPTED;
5092 
5093 	mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa));
5094 }
5095 
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)5096 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
5097 {
5098 	int idx;
5099 
5100 	if (vcpu->preempted) {
5101 		vcpu->arch.preempted_in_kernel = kvm_arch_vcpu_in_kernel(vcpu);
5102 
5103 		/*
5104 		 * Take the srcu lock as memslots will be accessed to check the gfn
5105 		 * cache generation against the memslots generation.
5106 		 */
5107 		idx = srcu_read_lock(&vcpu->kvm->srcu);
5108 		if (kvm_xen_msr_enabled(vcpu->kvm))
5109 			kvm_xen_runstate_set_preempted(vcpu);
5110 		else
5111 			kvm_steal_time_set_preempted(vcpu);
5112 		srcu_read_unlock(&vcpu->kvm->srcu, idx);
5113 	}
5114 
5115 	static_call(kvm_x86_vcpu_put)(vcpu);
5116 	vcpu->arch.last_host_tsc = rdtsc();
5117 }
5118 
kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu * vcpu,struct kvm_lapic_state * s)5119 static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu,
5120 				    struct kvm_lapic_state *s)
5121 {
5122 	static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu);
5123 
5124 	return kvm_apic_get_state(vcpu, s);
5125 }
5126 
kvm_vcpu_ioctl_set_lapic(struct kvm_vcpu * vcpu,struct kvm_lapic_state * s)5127 static int kvm_vcpu_ioctl_set_lapic(struct kvm_vcpu *vcpu,
5128 				    struct kvm_lapic_state *s)
5129 {
5130 	int r;
5131 
5132 	r = kvm_apic_set_state(vcpu, s);
5133 	if (r)
5134 		return r;
5135 	update_cr8_intercept(vcpu);
5136 
5137 	return 0;
5138 }
5139 
kvm_cpu_accept_dm_intr(struct kvm_vcpu * vcpu)5140 static int kvm_cpu_accept_dm_intr(struct kvm_vcpu *vcpu)
5141 {
5142 	/*
5143 	 * We can accept userspace's request for interrupt injection
5144 	 * as long as we have a place to store the interrupt number.
5145 	 * The actual injection will happen when the CPU is able to
5146 	 * deliver the interrupt.
5147 	 */
5148 	if (kvm_cpu_has_extint(vcpu))
5149 		return false;
5150 
5151 	/* Acknowledging ExtINT does not happen if LINT0 is masked.  */
5152 	return (!lapic_in_kernel(vcpu) ||
5153 		kvm_apic_accept_pic_intr(vcpu));
5154 }
5155 
kvm_vcpu_ready_for_interrupt_injection(struct kvm_vcpu * vcpu)5156 static int kvm_vcpu_ready_for_interrupt_injection(struct kvm_vcpu *vcpu)
5157 {
5158 	/*
5159 	 * Do not cause an interrupt window exit if an exception
5160 	 * is pending or an event needs reinjection; userspace
5161 	 * might want to inject the interrupt manually using KVM_SET_REGS
5162 	 * or KVM_SET_SREGS.  For that to work, we must be at an
5163 	 * instruction boundary and with no events half-injected.
5164 	 */
5165 	return (kvm_arch_interrupt_allowed(vcpu) &&
5166 		kvm_cpu_accept_dm_intr(vcpu) &&
5167 		!kvm_event_needs_reinjection(vcpu) &&
5168 		!kvm_is_exception_pending(vcpu));
5169 }
5170 
kvm_vcpu_ioctl_interrupt(struct kvm_vcpu * vcpu,struct kvm_interrupt * irq)5171 static int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
5172 				    struct kvm_interrupt *irq)
5173 {
5174 	if (irq->irq >= KVM_NR_INTERRUPTS)
5175 		return -EINVAL;
5176 
5177 	if (!irqchip_in_kernel(vcpu->kvm)) {
5178 		kvm_queue_interrupt(vcpu, irq->irq, false);
5179 		kvm_make_request(KVM_REQ_EVENT, vcpu);
5180 		return 0;
5181 	}
5182 
5183 	/*
5184 	 * With in-kernel LAPIC, we only use this to inject EXTINT, so
5185 	 * fail for in-kernel 8259.
5186 	 */
5187 	if (pic_in_kernel(vcpu->kvm))
5188 		return -ENXIO;
5189 
5190 	if (vcpu->arch.pending_external_vector != -1)
5191 		return -EEXIST;
5192 
5193 	vcpu->arch.pending_external_vector = irq->irq;
5194 	kvm_make_request(KVM_REQ_EVENT, vcpu);
5195 	return 0;
5196 }
5197 
kvm_vcpu_ioctl_nmi(struct kvm_vcpu * vcpu)5198 static int kvm_vcpu_ioctl_nmi(struct kvm_vcpu *vcpu)
5199 {
5200 	kvm_inject_nmi(vcpu);
5201 
5202 	return 0;
5203 }
5204 
vcpu_ioctl_tpr_access_reporting(struct kvm_vcpu * vcpu,struct kvm_tpr_access_ctl * tac)5205 static int vcpu_ioctl_tpr_access_reporting(struct kvm_vcpu *vcpu,
5206 					   struct kvm_tpr_access_ctl *tac)
5207 {
5208 	if (tac->flags)
5209 		return -EINVAL;
5210 	vcpu->arch.tpr_access_reporting = !!tac->enabled;
5211 	return 0;
5212 }
5213 
kvm_vcpu_ioctl_x86_setup_mce(struct kvm_vcpu * vcpu,u64 mcg_cap)5214 static int kvm_vcpu_ioctl_x86_setup_mce(struct kvm_vcpu *vcpu,
5215 					u64 mcg_cap)
5216 {
5217 	int r;
5218 	unsigned bank_num = mcg_cap & 0xff, bank;
5219 
5220 	r = -EINVAL;
5221 	if (!bank_num || bank_num > KVM_MAX_MCE_BANKS)
5222 		goto out;
5223 	if (mcg_cap & ~(kvm_caps.supported_mce_cap | 0xff | 0xff0000))
5224 		goto out;
5225 	r = 0;
5226 	vcpu->arch.mcg_cap = mcg_cap;
5227 	/* Init IA32_MCG_CTL to all 1s */
5228 	if (mcg_cap & MCG_CTL_P)
5229 		vcpu->arch.mcg_ctl = ~(u64)0;
5230 	/* Init IA32_MCi_CTL to all 1s, IA32_MCi_CTL2 to all 0s */
5231 	for (bank = 0; bank < bank_num; bank++) {
5232 		vcpu->arch.mce_banks[bank*4] = ~(u64)0;
5233 		if (mcg_cap & MCG_CMCI_P)
5234 			vcpu->arch.mci_ctl2_banks[bank] = 0;
5235 	}
5236 
5237 	kvm_apic_after_set_mcg_cap(vcpu);
5238 
5239 	static_call(kvm_x86_setup_mce)(vcpu);
5240 out:
5241 	return r;
5242 }
5243 
5244 /*
5245  * Validate this is an UCNA (uncorrectable no action) error by checking the
5246  * MCG_STATUS and MCi_STATUS registers:
5247  * - none of the bits for Machine Check Exceptions are set
5248  * - both the VAL (valid) and UC (uncorrectable) bits are set
5249  * MCI_STATUS_PCC - Processor Context Corrupted
5250  * MCI_STATUS_S - Signaled as a Machine Check Exception
5251  * MCI_STATUS_AR - Software recoverable Action Required
5252  */
is_ucna(struct kvm_x86_mce * mce)5253 static bool is_ucna(struct kvm_x86_mce *mce)
5254 {
5255 	return	!mce->mcg_status &&
5256 		!(mce->status & (MCI_STATUS_PCC | MCI_STATUS_S | MCI_STATUS_AR)) &&
5257 		(mce->status & MCI_STATUS_VAL) &&
5258 		(mce->status & MCI_STATUS_UC);
5259 }
5260 
kvm_vcpu_x86_set_ucna(struct kvm_vcpu * vcpu,struct kvm_x86_mce * mce,u64 * banks)5261 static int kvm_vcpu_x86_set_ucna(struct kvm_vcpu *vcpu, struct kvm_x86_mce *mce, u64* banks)
5262 {
5263 	u64 mcg_cap = vcpu->arch.mcg_cap;
5264 
5265 	banks[1] = mce->status;
5266 	banks[2] = mce->addr;
5267 	banks[3] = mce->misc;
5268 	vcpu->arch.mcg_status = mce->mcg_status;
5269 
5270 	if (!(mcg_cap & MCG_CMCI_P) ||
5271 	    !(vcpu->arch.mci_ctl2_banks[mce->bank] & MCI_CTL2_CMCI_EN))
5272 		return 0;
5273 
5274 	if (lapic_in_kernel(vcpu))
5275 		kvm_apic_local_deliver(vcpu->arch.apic, APIC_LVTCMCI);
5276 
5277 	return 0;
5278 }
5279 
kvm_vcpu_ioctl_x86_set_mce(struct kvm_vcpu * vcpu,struct kvm_x86_mce * mce)5280 static int kvm_vcpu_ioctl_x86_set_mce(struct kvm_vcpu *vcpu,
5281 				      struct kvm_x86_mce *mce)
5282 {
5283 	u64 mcg_cap = vcpu->arch.mcg_cap;
5284 	unsigned bank_num = mcg_cap & 0xff;
5285 	u64 *banks = vcpu->arch.mce_banks;
5286 
5287 	if (mce->bank >= bank_num || !(mce->status & MCI_STATUS_VAL))
5288 		return -EINVAL;
5289 
5290 	banks += array_index_nospec(4 * mce->bank, 4 * bank_num);
5291 
5292 	if (is_ucna(mce))
5293 		return kvm_vcpu_x86_set_ucna(vcpu, mce, banks);
5294 
5295 	/*
5296 	 * if IA32_MCG_CTL is not all 1s, the uncorrected error
5297 	 * reporting is disabled
5298 	 */
5299 	if ((mce->status & MCI_STATUS_UC) && (mcg_cap & MCG_CTL_P) &&
5300 	    vcpu->arch.mcg_ctl != ~(u64)0)
5301 		return 0;
5302 	/*
5303 	 * if IA32_MCi_CTL is not all 1s, the uncorrected error
5304 	 * reporting is disabled for the bank
5305 	 */
5306 	if ((mce->status & MCI_STATUS_UC) && banks[0] != ~(u64)0)
5307 		return 0;
5308 	if (mce->status & MCI_STATUS_UC) {
5309 		if ((vcpu->arch.mcg_status & MCG_STATUS_MCIP) ||
5310 		    !kvm_is_cr4_bit_set(vcpu, X86_CR4_MCE)) {
5311 			kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
5312 			return 0;
5313 		}
5314 		if (banks[1] & MCI_STATUS_VAL)
5315 			mce->status |= MCI_STATUS_OVER;
5316 		banks[2] = mce->addr;
5317 		banks[3] = mce->misc;
5318 		vcpu->arch.mcg_status = mce->mcg_status;
5319 		banks[1] = mce->status;
5320 		kvm_queue_exception(vcpu, MC_VECTOR);
5321 	} else if (!(banks[1] & MCI_STATUS_VAL)
5322 		   || !(banks[1] & MCI_STATUS_UC)) {
5323 		if (banks[1] & MCI_STATUS_VAL)
5324 			mce->status |= MCI_STATUS_OVER;
5325 		banks[2] = mce->addr;
5326 		banks[3] = mce->misc;
5327 		banks[1] = mce->status;
5328 	} else
5329 		banks[1] |= MCI_STATUS_OVER;
5330 	return 0;
5331 }
5332 
kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)5333 static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
5334 					       struct kvm_vcpu_events *events)
5335 {
5336 	struct kvm_queued_exception *ex;
5337 
5338 	process_nmi(vcpu);
5339 
5340 #ifdef CONFIG_KVM_SMM
5341 	if (kvm_check_request(KVM_REQ_SMI, vcpu))
5342 		process_smi(vcpu);
5343 #endif
5344 
5345 	/*
5346 	 * KVM's ABI only allows for one exception to be migrated.  Luckily,
5347 	 * the only time there can be two queued exceptions is if there's a
5348 	 * non-exiting _injected_ exception, and a pending exiting exception.
5349 	 * In that case, ignore the VM-Exiting exception as it's an extension
5350 	 * of the injected exception.
5351 	 */
5352 	if (vcpu->arch.exception_vmexit.pending &&
5353 	    !vcpu->arch.exception.pending &&
5354 	    !vcpu->arch.exception.injected)
5355 		ex = &vcpu->arch.exception_vmexit;
5356 	else
5357 		ex = &vcpu->arch.exception;
5358 
5359 	/*
5360 	 * In guest mode, payload delivery should be deferred if the exception
5361 	 * will be intercepted by L1, e.g. KVM should not modifying CR2 if L1
5362 	 * intercepts #PF, ditto for DR6 and #DBs.  If the per-VM capability,
5363 	 * KVM_CAP_EXCEPTION_PAYLOAD, is not set, userspace may or may not
5364 	 * propagate the payload and so it cannot be safely deferred.  Deliver
5365 	 * the payload if the capability hasn't been requested.
5366 	 */
5367 	if (!vcpu->kvm->arch.exception_payload_enabled &&
5368 	    ex->pending && ex->has_payload)
5369 		kvm_deliver_exception_payload(vcpu, ex);
5370 
5371 	memset(events, 0, sizeof(*events));
5372 
5373 	/*
5374 	 * The API doesn't provide the instruction length for software
5375 	 * exceptions, so don't report them. As long as the guest RIP
5376 	 * isn't advanced, we should expect to encounter the exception
5377 	 * again.
5378 	 */
5379 	if (!kvm_exception_is_soft(ex->vector)) {
5380 		events->exception.injected = ex->injected;
5381 		events->exception.pending = ex->pending;
5382 		/*
5383 		 * For ABI compatibility, deliberately conflate
5384 		 * pending and injected exceptions when
5385 		 * KVM_CAP_EXCEPTION_PAYLOAD isn't enabled.
5386 		 */
5387 		if (!vcpu->kvm->arch.exception_payload_enabled)
5388 			events->exception.injected |= ex->pending;
5389 	}
5390 	events->exception.nr = ex->vector;
5391 	events->exception.has_error_code = ex->has_error_code;
5392 	events->exception.error_code = ex->error_code;
5393 	events->exception_has_payload = ex->has_payload;
5394 	events->exception_payload = ex->payload;
5395 
5396 	events->interrupt.injected =
5397 		vcpu->arch.interrupt.injected && !vcpu->arch.interrupt.soft;
5398 	events->interrupt.nr = vcpu->arch.interrupt.nr;
5399 	events->interrupt.shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu);
5400 
5401 	events->nmi.injected = vcpu->arch.nmi_injected;
5402 	events->nmi.pending = kvm_get_nr_pending_nmis(vcpu);
5403 	events->nmi.masked = static_call(kvm_x86_get_nmi_mask)(vcpu);
5404 
5405 	/* events->sipi_vector is never valid when reporting to user space */
5406 
5407 #ifdef CONFIG_KVM_SMM
5408 	events->smi.smm = is_smm(vcpu);
5409 	events->smi.pending = vcpu->arch.smi_pending;
5410 	events->smi.smm_inside_nmi =
5411 		!!(vcpu->arch.hflags & HF_SMM_INSIDE_NMI_MASK);
5412 #endif
5413 	events->smi.latched_init = kvm_lapic_latched_init(vcpu);
5414 
5415 	events->flags = (KVM_VCPUEVENT_VALID_NMI_PENDING
5416 			 | KVM_VCPUEVENT_VALID_SHADOW
5417 			 | KVM_VCPUEVENT_VALID_SMM);
5418 	if (vcpu->kvm->arch.exception_payload_enabled)
5419 		events->flags |= KVM_VCPUEVENT_VALID_PAYLOAD;
5420 	if (vcpu->kvm->arch.triple_fault_event) {
5421 		events->triple_fault.pending = kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu);
5422 		events->flags |= KVM_VCPUEVENT_VALID_TRIPLE_FAULT;
5423 	}
5424 }
5425 
kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)5426 static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
5427 					      struct kvm_vcpu_events *events)
5428 {
5429 	if (events->flags & ~(KVM_VCPUEVENT_VALID_NMI_PENDING
5430 			      | KVM_VCPUEVENT_VALID_SIPI_VECTOR
5431 			      | KVM_VCPUEVENT_VALID_SHADOW
5432 			      | KVM_VCPUEVENT_VALID_SMM
5433 			      | KVM_VCPUEVENT_VALID_PAYLOAD
5434 			      | KVM_VCPUEVENT_VALID_TRIPLE_FAULT))
5435 		return -EINVAL;
5436 
5437 	if (events->flags & KVM_VCPUEVENT_VALID_PAYLOAD) {
5438 		if (!vcpu->kvm->arch.exception_payload_enabled)
5439 			return -EINVAL;
5440 		if (events->exception.pending)
5441 			events->exception.injected = 0;
5442 		else
5443 			events->exception_has_payload = 0;
5444 	} else {
5445 		events->exception.pending = 0;
5446 		events->exception_has_payload = 0;
5447 	}
5448 
5449 	if ((events->exception.injected || events->exception.pending) &&
5450 	    (events->exception.nr > 31 || events->exception.nr == NMI_VECTOR))
5451 		return -EINVAL;
5452 
5453 	/* INITs are latched while in SMM */
5454 	if (events->flags & KVM_VCPUEVENT_VALID_SMM &&
5455 	    (events->smi.smm || events->smi.pending) &&
5456 	    vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED)
5457 		return -EINVAL;
5458 
5459 	process_nmi(vcpu);
5460 
5461 	/*
5462 	 * Flag that userspace is stuffing an exception, the next KVM_RUN will
5463 	 * morph the exception to a VM-Exit if appropriate.  Do this only for
5464 	 * pending exceptions, already-injected exceptions are not subject to
5465 	 * intercpetion.  Note, userspace that conflates pending and injected
5466 	 * is hosed, and will incorrectly convert an injected exception into a
5467 	 * pending exception, which in turn may cause a spurious VM-Exit.
5468 	 */
5469 	vcpu->arch.exception_from_userspace = events->exception.pending;
5470 
5471 	vcpu->arch.exception_vmexit.pending = false;
5472 
5473 	vcpu->arch.exception.injected = events->exception.injected;
5474 	vcpu->arch.exception.pending = events->exception.pending;
5475 	vcpu->arch.exception.vector = events->exception.nr;
5476 	vcpu->arch.exception.has_error_code = events->exception.has_error_code;
5477 	vcpu->arch.exception.error_code = events->exception.error_code;
5478 	vcpu->arch.exception.has_payload = events->exception_has_payload;
5479 	vcpu->arch.exception.payload = events->exception_payload;
5480 
5481 	vcpu->arch.interrupt.injected = events->interrupt.injected;
5482 	vcpu->arch.interrupt.nr = events->interrupt.nr;
5483 	vcpu->arch.interrupt.soft = events->interrupt.soft;
5484 	if (events->flags & KVM_VCPUEVENT_VALID_SHADOW)
5485 		static_call(kvm_x86_set_interrupt_shadow)(vcpu,
5486 						events->interrupt.shadow);
5487 
5488 	vcpu->arch.nmi_injected = events->nmi.injected;
5489 	if (events->flags & KVM_VCPUEVENT_VALID_NMI_PENDING) {
5490 		vcpu->arch.nmi_pending = 0;
5491 		atomic_set(&vcpu->arch.nmi_queued, events->nmi.pending);
5492 		if (events->nmi.pending)
5493 			kvm_make_request(KVM_REQ_NMI, vcpu);
5494 	}
5495 	static_call(kvm_x86_set_nmi_mask)(vcpu, events->nmi.masked);
5496 
5497 	if (events->flags & KVM_VCPUEVENT_VALID_SIPI_VECTOR &&
5498 	    lapic_in_kernel(vcpu))
5499 		vcpu->arch.apic->sipi_vector = events->sipi_vector;
5500 
5501 	if (events->flags & KVM_VCPUEVENT_VALID_SMM) {
5502 #ifdef CONFIG_KVM_SMM
5503 		if (!!(vcpu->arch.hflags & HF_SMM_MASK) != events->smi.smm) {
5504 			kvm_leave_nested(vcpu);
5505 			kvm_smm_changed(vcpu, events->smi.smm);
5506 		}
5507 
5508 		vcpu->arch.smi_pending = events->smi.pending;
5509 
5510 		if (events->smi.smm) {
5511 			if (events->smi.smm_inside_nmi)
5512 				vcpu->arch.hflags |= HF_SMM_INSIDE_NMI_MASK;
5513 			else
5514 				vcpu->arch.hflags &= ~HF_SMM_INSIDE_NMI_MASK;
5515 		}
5516 
5517 #else
5518 		if (events->smi.smm || events->smi.pending ||
5519 		    events->smi.smm_inside_nmi)
5520 			return -EINVAL;
5521 #endif
5522 
5523 		if (lapic_in_kernel(vcpu)) {
5524 			if (events->smi.latched_init)
5525 				set_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
5526 			else
5527 				clear_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
5528 		}
5529 	}
5530 
5531 	if (events->flags & KVM_VCPUEVENT_VALID_TRIPLE_FAULT) {
5532 		if (!vcpu->kvm->arch.triple_fault_event)
5533 			return -EINVAL;
5534 		if (events->triple_fault.pending)
5535 			kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
5536 		else
5537 			kvm_clear_request(KVM_REQ_TRIPLE_FAULT, vcpu);
5538 	}
5539 
5540 	kvm_make_request(KVM_REQ_EVENT, vcpu);
5541 
5542 	return 0;
5543 }
5544 
kvm_vcpu_ioctl_x86_get_debugregs(struct kvm_vcpu * vcpu,struct kvm_debugregs * dbgregs)5545 static int kvm_vcpu_ioctl_x86_get_debugregs(struct kvm_vcpu *vcpu,
5546 					    struct kvm_debugregs *dbgregs)
5547 {
5548 	unsigned int i;
5549 
5550 	if (vcpu->kvm->arch.has_protected_state &&
5551 	    vcpu->arch.guest_state_protected)
5552 		return -EINVAL;
5553 
5554 	memset(dbgregs, 0, sizeof(*dbgregs));
5555 
5556 	BUILD_BUG_ON(ARRAY_SIZE(vcpu->arch.db) != ARRAY_SIZE(dbgregs->db));
5557 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.db); i++)
5558 		dbgregs->db[i] = vcpu->arch.db[i];
5559 
5560 	dbgregs->dr6 = vcpu->arch.dr6;
5561 	dbgregs->dr7 = vcpu->arch.dr7;
5562 	return 0;
5563 }
5564 
kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu * vcpu,struct kvm_debugregs * dbgregs)5565 static int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu,
5566 					    struct kvm_debugregs *dbgregs)
5567 {
5568 	unsigned int i;
5569 
5570 	if (vcpu->kvm->arch.has_protected_state &&
5571 	    vcpu->arch.guest_state_protected)
5572 		return -EINVAL;
5573 
5574 	if (dbgregs->flags)
5575 		return -EINVAL;
5576 
5577 	if (!kvm_dr6_valid(dbgregs->dr6))
5578 		return -EINVAL;
5579 	if (!kvm_dr7_valid(dbgregs->dr7))
5580 		return -EINVAL;
5581 
5582 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.db); i++)
5583 		vcpu->arch.db[i] = dbgregs->db[i];
5584 
5585 	kvm_update_dr0123(vcpu);
5586 	vcpu->arch.dr6 = dbgregs->dr6;
5587 	vcpu->arch.dr7 = dbgregs->dr7;
5588 	kvm_update_dr7(vcpu);
5589 
5590 	return 0;
5591 }
5592 
5593 
kvm_vcpu_ioctl_x86_get_xsave2(struct kvm_vcpu * vcpu,u8 * state,unsigned int size)5594 static int kvm_vcpu_ioctl_x86_get_xsave2(struct kvm_vcpu *vcpu,
5595 					 u8 *state, unsigned int size)
5596 {
5597 	/*
5598 	 * Only copy state for features that are enabled for the guest.  The
5599 	 * state itself isn't problematic, but setting bits in the header for
5600 	 * features that are supported in *this* host but not exposed to the
5601 	 * guest can result in KVM_SET_XSAVE failing when live migrating to a
5602 	 * compatible host without the features that are NOT exposed to the
5603 	 * guest.
5604 	 *
5605 	 * FP+SSE can always be saved/restored via KVM_{G,S}ET_XSAVE, even if
5606 	 * XSAVE/XCRO are not exposed to the guest, and even if XSAVE isn't
5607 	 * supported by the host.
5608 	 */
5609 	u64 supported_xcr0 = vcpu->arch.guest_supported_xcr0 |
5610 			     XFEATURE_MASK_FPSSE;
5611 
5612 	if (fpstate_is_confidential(&vcpu->arch.guest_fpu))
5613 		return vcpu->kvm->arch.has_protected_state ? -EINVAL : 0;
5614 
5615 	fpu_copy_guest_fpstate_to_uabi(&vcpu->arch.guest_fpu, state, size,
5616 				       supported_xcr0, vcpu->arch.pkru);
5617 	return 0;
5618 }
5619 
kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu * vcpu,struct kvm_xsave * guest_xsave)5620 static int kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu *vcpu,
5621 					struct kvm_xsave *guest_xsave)
5622 {
5623 	return kvm_vcpu_ioctl_x86_get_xsave2(vcpu, (void *)guest_xsave->region,
5624 					     sizeof(guest_xsave->region));
5625 }
5626 
kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu * vcpu,struct kvm_xsave * guest_xsave)5627 static int kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu *vcpu,
5628 					struct kvm_xsave *guest_xsave)
5629 {
5630 	if (fpstate_is_confidential(&vcpu->arch.guest_fpu))
5631 		return vcpu->kvm->arch.has_protected_state ? -EINVAL : 0;
5632 
5633 	return fpu_copy_uabi_to_guest_fpstate(&vcpu->arch.guest_fpu,
5634 					      guest_xsave->region,
5635 					      kvm_caps.supported_xcr0,
5636 					      &vcpu->arch.pkru);
5637 }
5638 
kvm_vcpu_ioctl_x86_get_xcrs(struct kvm_vcpu * vcpu,struct kvm_xcrs * guest_xcrs)5639 static int kvm_vcpu_ioctl_x86_get_xcrs(struct kvm_vcpu *vcpu,
5640 				       struct kvm_xcrs *guest_xcrs)
5641 {
5642 	if (vcpu->kvm->arch.has_protected_state &&
5643 	    vcpu->arch.guest_state_protected)
5644 		return -EINVAL;
5645 
5646 	if (!boot_cpu_has(X86_FEATURE_XSAVE)) {
5647 		guest_xcrs->nr_xcrs = 0;
5648 		return 0;
5649 	}
5650 
5651 	guest_xcrs->nr_xcrs = 1;
5652 	guest_xcrs->flags = 0;
5653 	guest_xcrs->xcrs[0].xcr = XCR_XFEATURE_ENABLED_MASK;
5654 	guest_xcrs->xcrs[0].value = vcpu->arch.xcr0;
5655 	return 0;
5656 }
5657 
kvm_vcpu_ioctl_x86_set_xcrs(struct kvm_vcpu * vcpu,struct kvm_xcrs * guest_xcrs)5658 static int kvm_vcpu_ioctl_x86_set_xcrs(struct kvm_vcpu *vcpu,
5659 				       struct kvm_xcrs *guest_xcrs)
5660 {
5661 	int i, r = 0;
5662 
5663 	if (vcpu->kvm->arch.has_protected_state &&
5664 	    vcpu->arch.guest_state_protected)
5665 		return -EINVAL;
5666 
5667 	if (!boot_cpu_has(X86_FEATURE_XSAVE))
5668 		return -EINVAL;
5669 
5670 	if (guest_xcrs->nr_xcrs > KVM_MAX_XCRS || guest_xcrs->flags)
5671 		return -EINVAL;
5672 
5673 	for (i = 0; i < guest_xcrs->nr_xcrs; i++)
5674 		/* Only support XCR0 currently */
5675 		if (guest_xcrs->xcrs[i].xcr == XCR_XFEATURE_ENABLED_MASK) {
5676 			r = __kvm_set_xcr(vcpu, XCR_XFEATURE_ENABLED_MASK,
5677 				guest_xcrs->xcrs[i].value);
5678 			break;
5679 		}
5680 	if (r)
5681 		r = -EINVAL;
5682 	return r;
5683 }
5684 
5685 /*
5686  * kvm_set_guest_paused() indicates to the guest kernel that it has been
5687  * stopped by the hypervisor.  This function will be called from the host only.
5688  * EINVAL is returned when the host attempts to set the flag for a guest that
5689  * does not support pv clocks.
5690  */
kvm_set_guest_paused(struct kvm_vcpu * vcpu)5691 static int kvm_set_guest_paused(struct kvm_vcpu *vcpu)
5692 {
5693 	if (!vcpu->arch.pv_time.active)
5694 		return -EINVAL;
5695 	vcpu->arch.pvclock_set_guest_stopped_request = true;
5696 	kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
5697 	return 0;
5698 }
5699 
kvm_arch_tsc_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)5700 static int kvm_arch_tsc_has_attr(struct kvm_vcpu *vcpu,
5701 				 struct kvm_device_attr *attr)
5702 {
5703 	int r;
5704 
5705 	switch (attr->attr) {
5706 	case KVM_VCPU_TSC_OFFSET:
5707 		r = 0;
5708 		break;
5709 	default:
5710 		r = -ENXIO;
5711 	}
5712 
5713 	return r;
5714 }
5715 
kvm_arch_tsc_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)5716 static int kvm_arch_tsc_get_attr(struct kvm_vcpu *vcpu,
5717 				 struct kvm_device_attr *attr)
5718 {
5719 	u64 __user *uaddr = u64_to_user_ptr(attr->addr);
5720 	int r;
5721 
5722 	switch (attr->attr) {
5723 	case KVM_VCPU_TSC_OFFSET:
5724 		r = -EFAULT;
5725 		if (put_user(vcpu->arch.l1_tsc_offset, uaddr))
5726 			break;
5727 		r = 0;
5728 		break;
5729 	default:
5730 		r = -ENXIO;
5731 	}
5732 
5733 	return r;
5734 }
5735 
kvm_arch_tsc_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)5736 static int kvm_arch_tsc_set_attr(struct kvm_vcpu *vcpu,
5737 				 struct kvm_device_attr *attr)
5738 {
5739 	u64 __user *uaddr = u64_to_user_ptr(attr->addr);
5740 	struct kvm *kvm = vcpu->kvm;
5741 	int r;
5742 
5743 	switch (attr->attr) {
5744 	case KVM_VCPU_TSC_OFFSET: {
5745 		u64 offset, tsc, ns;
5746 		unsigned long flags;
5747 		bool matched;
5748 
5749 		r = -EFAULT;
5750 		if (get_user(offset, uaddr))
5751 			break;
5752 
5753 		raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags);
5754 
5755 		matched = (vcpu->arch.virtual_tsc_khz &&
5756 			   kvm->arch.last_tsc_khz == vcpu->arch.virtual_tsc_khz &&
5757 			   kvm->arch.last_tsc_offset == offset);
5758 
5759 		tsc = kvm_scale_tsc(rdtsc(), vcpu->arch.l1_tsc_scaling_ratio) + offset;
5760 		ns = get_kvmclock_base_ns();
5761 
5762 		kvm->arch.user_set_tsc = true;
5763 		__kvm_synchronize_tsc(vcpu, offset, tsc, ns, matched);
5764 		raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags);
5765 
5766 		r = 0;
5767 		break;
5768 	}
5769 	default:
5770 		r = -ENXIO;
5771 	}
5772 
5773 	return r;
5774 }
5775 
kvm_vcpu_ioctl_device_attr(struct kvm_vcpu * vcpu,unsigned int ioctl,void __user * argp)5776 static int kvm_vcpu_ioctl_device_attr(struct kvm_vcpu *vcpu,
5777 				      unsigned int ioctl,
5778 				      void __user *argp)
5779 {
5780 	struct kvm_device_attr attr;
5781 	int r;
5782 
5783 	if (copy_from_user(&attr, argp, sizeof(attr)))
5784 		return -EFAULT;
5785 
5786 	if (attr.group != KVM_VCPU_TSC_CTRL)
5787 		return -ENXIO;
5788 
5789 	switch (ioctl) {
5790 	case KVM_HAS_DEVICE_ATTR:
5791 		r = kvm_arch_tsc_has_attr(vcpu, &attr);
5792 		break;
5793 	case KVM_GET_DEVICE_ATTR:
5794 		r = kvm_arch_tsc_get_attr(vcpu, &attr);
5795 		break;
5796 	case KVM_SET_DEVICE_ATTR:
5797 		r = kvm_arch_tsc_set_attr(vcpu, &attr);
5798 		break;
5799 	}
5800 
5801 	return r;
5802 }
5803 
kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu * vcpu,struct kvm_enable_cap * cap)5804 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
5805 				     struct kvm_enable_cap *cap)
5806 {
5807 	if (cap->flags)
5808 		return -EINVAL;
5809 
5810 	switch (cap->cap) {
5811 #ifdef CONFIG_KVM_HYPERV
5812 	case KVM_CAP_HYPERV_SYNIC2:
5813 		if (cap->args[0])
5814 			return -EINVAL;
5815 		fallthrough;
5816 
5817 	case KVM_CAP_HYPERV_SYNIC:
5818 		if (!irqchip_in_kernel(vcpu->kvm))
5819 			return -EINVAL;
5820 		return kvm_hv_activate_synic(vcpu, cap->cap ==
5821 					     KVM_CAP_HYPERV_SYNIC2);
5822 	case KVM_CAP_HYPERV_ENLIGHTENED_VMCS:
5823 		{
5824 			int r;
5825 			uint16_t vmcs_version;
5826 			void __user *user_ptr;
5827 
5828 			if (!kvm_x86_ops.nested_ops->enable_evmcs)
5829 				return -ENOTTY;
5830 			r = kvm_x86_ops.nested_ops->enable_evmcs(vcpu, &vmcs_version);
5831 			if (!r) {
5832 				user_ptr = (void __user *)(uintptr_t)cap->args[0];
5833 				if (copy_to_user(user_ptr, &vmcs_version,
5834 						 sizeof(vmcs_version)))
5835 					r = -EFAULT;
5836 			}
5837 			return r;
5838 		}
5839 	case KVM_CAP_HYPERV_DIRECT_TLBFLUSH:
5840 		if (!kvm_x86_ops.enable_l2_tlb_flush)
5841 			return -ENOTTY;
5842 
5843 		return static_call(kvm_x86_enable_l2_tlb_flush)(vcpu);
5844 
5845 	case KVM_CAP_HYPERV_ENFORCE_CPUID:
5846 		return kvm_hv_set_enforce_cpuid(vcpu, cap->args[0]);
5847 #endif
5848 
5849 	case KVM_CAP_ENFORCE_PV_FEATURE_CPUID:
5850 		vcpu->arch.pv_cpuid.enforce = cap->args[0];
5851 		if (vcpu->arch.pv_cpuid.enforce)
5852 			kvm_update_pv_runtime(vcpu);
5853 
5854 		return 0;
5855 	default:
5856 		return -EINVAL;
5857 	}
5858 }
5859 
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)5860 long kvm_arch_vcpu_ioctl(struct file *filp,
5861 			 unsigned int ioctl, unsigned long arg)
5862 {
5863 	struct kvm_vcpu *vcpu = filp->private_data;
5864 	void __user *argp = (void __user *)arg;
5865 	int r;
5866 	union {
5867 		struct kvm_sregs2 *sregs2;
5868 		struct kvm_lapic_state *lapic;
5869 		struct kvm_xsave *xsave;
5870 		struct kvm_xcrs *xcrs;
5871 		void *buffer;
5872 	} u;
5873 
5874 	vcpu_load(vcpu);
5875 
5876 	u.buffer = NULL;
5877 	switch (ioctl) {
5878 	case KVM_GET_LAPIC: {
5879 		r = -EINVAL;
5880 		if (!lapic_in_kernel(vcpu))
5881 			goto out;
5882 		u.lapic = kzalloc(sizeof(struct kvm_lapic_state),
5883 				GFP_KERNEL_ACCOUNT);
5884 
5885 		r = -ENOMEM;
5886 		if (!u.lapic)
5887 			goto out;
5888 		r = kvm_vcpu_ioctl_get_lapic(vcpu, u.lapic);
5889 		if (r)
5890 			goto out;
5891 		r = -EFAULT;
5892 		if (copy_to_user(argp, u.lapic, sizeof(struct kvm_lapic_state)))
5893 			goto out;
5894 		r = 0;
5895 		break;
5896 	}
5897 	case KVM_SET_LAPIC: {
5898 		r = -EINVAL;
5899 		if (!lapic_in_kernel(vcpu))
5900 			goto out;
5901 		u.lapic = memdup_user(argp, sizeof(*u.lapic));
5902 		if (IS_ERR(u.lapic)) {
5903 			r = PTR_ERR(u.lapic);
5904 			goto out_nofree;
5905 		}
5906 
5907 		r = kvm_vcpu_ioctl_set_lapic(vcpu, u.lapic);
5908 		break;
5909 	}
5910 	case KVM_INTERRUPT: {
5911 		struct kvm_interrupt irq;
5912 
5913 		r = -EFAULT;
5914 		if (copy_from_user(&irq, argp, sizeof(irq)))
5915 			goto out;
5916 		r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
5917 		break;
5918 	}
5919 	case KVM_NMI: {
5920 		r = kvm_vcpu_ioctl_nmi(vcpu);
5921 		break;
5922 	}
5923 	case KVM_SMI: {
5924 		r = kvm_inject_smi(vcpu);
5925 		break;
5926 	}
5927 	case KVM_SET_CPUID: {
5928 		struct kvm_cpuid __user *cpuid_arg = argp;
5929 		struct kvm_cpuid cpuid;
5930 
5931 		r = -EFAULT;
5932 		if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
5933 			goto out;
5934 		r = kvm_vcpu_ioctl_set_cpuid(vcpu, &cpuid, cpuid_arg->entries);
5935 		break;
5936 	}
5937 	case KVM_SET_CPUID2: {
5938 		struct kvm_cpuid2 __user *cpuid_arg = argp;
5939 		struct kvm_cpuid2 cpuid;
5940 
5941 		r = -EFAULT;
5942 		if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
5943 			goto out;
5944 		r = kvm_vcpu_ioctl_set_cpuid2(vcpu, &cpuid,
5945 					      cpuid_arg->entries);
5946 		break;
5947 	}
5948 	case KVM_GET_CPUID2: {
5949 		struct kvm_cpuid2 __user *cpuid_arg = argp;
5950 		struct kvm_cpuid2 cpuid;
5951 
5952 		r = -EFAULT;
5953 		if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
5954 			goto out;
5955 		r = kvm_vcpu_ioctl_get_cpuid2(vcpu, &cpuid,
5956 					      cpuid_arg->entries);
5957 		if (r)
5958 			goto out;
5959 		r = -EFAULT;
5960 		if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid)))
5961 			goto out;
5962 		r = 0;
5963 		break;
5964 	}
5965 	case KVM_GET_MSRS: {
5966 		int idx = srcu_read_lock(&vcpu->kvm->srcu);
5967 		r = msr_io(vcpu, argp, do_get_msr, 1);
5968 		srcu_read_unlock(&vcpu->kvm->srcu, idx);
5969 		break;
5970 	}
5971 	case KVM_SET_MSRS: {
5972 		int idx = srcu_read_lock(&vcpu->kvm->srcu);
5973 		r = msr_io(vcpu, argp, do_set_msr, 0);
5974 		srcu_read_unlock(&vcpu->kvm->srcu, idx);
5975 		break;
5976 	}
5977 	case KVM_TPR_ACCESS_REPORTING: {
5978 		struct kvm_tpr_access_ctl tac;
5979 
5980 		r = -EFAULT;
5981 		if (copy_from_user(&tac, argp, sizeof(tac)))
5982 			goto out;
5983 		r = vcpu_ioctl_tpr_access_reporting(vcpu, &tac);
5984 		if (r)
5985 			goto out;
5986 		r = -EFAULT;
5987 		if (copy_to_user(argp, &tac, sizeof(tac)))
5988 			goto out;
5989 		r = 0;
5990 		break;
5991 	};
5992 	case KVM_SET_VAPIC_ADDR: {
5993 		struct kvm_vapic_addr va;
5994 		int idx;
5995 
5996 		r = -EINVAL;
5997 		if (!lapic_in_kernel(vcpu))
5998 			goto out;
5999 		r = -EFAULT;
6000 		if (copy_from_user(&va, argp, sizeof(va)))
6001 			goto out;
6002 		idx = srcu_read_lock(&vcpu->kvm->srcu);
6003 		r = kvm_lapic_set_vapic_addr(vcpu, va.vapic_addr);
6004 		srcu_read_unlock(&vcpu->kvm->srcu, idx);
6005 		break;
6006 	}
6007 	case KVM_X86_SETUP_MCE: {
6008 		u64 mcg_cap;
6009 
6010 		r = -EFAULT;
6011 		if (copy_from_user(&mcg_cap, argp, sizeof(mcg_cap)))
6012 			goto out;
6013 		r = kvm_vcpu_ioctl_x86_setup_mce(vcpu, mcg_cap);
6014 		break;
6015 	}
6016 	case KVM_X86_SET_MCE: {
6017 		struct kvm_x86_mce mce;
6018 
6019 		r = -EFAULT;
6020 		if (copy_from_user(&mce, argp, sizeof(mce)))
6021 			goto out;
6022 		r = kvm_vcpu_ioctl_x86_set_mce(vcpu, &mce);
6023 		break;
6024 	}
6025 	case KVM_GET_VCPU_EVENTS: {
6026 		struct kvm_vcpu_events events;
6027 
6028 		kvm_vcpu_ioctl_x86_get_vcpu_events(vcpu, &events);
6029 
6030 		r = -EFAULT;
6031 		if (copy_to_user(argp, &events, sizeof(struct kvm_vcpu_events)))
6032 			break;
6033 		r = 0;
6034 		break;
6035 	}
6036 	case KVM_SET_VCPU_EVENTS: {
6037 		struct kvm_vcpu_events events;
6038 
6039 		r = -EFAULT;
6040 		if (copy_from_user(&events, argp, sizeof(struct kvm_vcpu_events)))
6041 			break;
6042 
6043 		r = kvm_vcpu_ioctl_x86_set_vcpu_events(vcpu, &events);
6044 		break;
6045 	}
6046 	case KVM_GET_DEBUGREGS: {
6047 		struct kvm_debugregs dbgregs;
6048 
6049 		r = kvm_vcpu_ioctl_x86_get_debugregs(vcpu, &dbgregs);
6050 		if (r < 0)
6051 			break;
6052 
6053 		r = -EFAULT;
6054 		if (copy_to_user(argp, &dbgregs,
6055 				 sizeof(struct kvm_debugregs)))
6056 			break;
6057 		r = 0;
6058 		break;
6059 	}
6060 	case KVM_SET_DEBUGREGS: {
6061 		struct kvm_debugregs dbgregs;
6062 
6063 		r = -EFAULT;
6064 		if (copy_from_user(&dbgregs, argp,
6065 				   sizeof(struct kvm_debugregs)))
6066 			break;
6067 
6068 		r = kvm_vcpu_ioctl_x86_set_debugregs(vcpu, &dbgregs);
6069 		break;
6070 	}
6071 	case KVM_GET_XSAVE: {
6072 		r = -EINVAL;
6073 		if (vcpu->arch.guest_fpu.uabi_size > sizeof(struct kvm_xsave))
6074 			break;
6075 
6076 		u.xsave = kzalloc(sizeof(struct kvm_xsave), GFP_KERNEL_ACCOUNT);
6077 		r = -ENOMEM;
6078 		if (!u.xsave)
6079 			break;
6080 
6081 		r = kvm_vcpu_ioctl_x86_get_xsave(vcpu, u.xsave);
6082 		if (r < 0)
6083 			break;
6084 
6085 		r = -EFAULT;
6086 		if (copy_to_user(argp, u.xsave, sizeof(struct kvm_xsave)))
6087 			break;
6088 		r = 0;
6089 		break;
6090 	}
6091 	case KVM_SET_XSAVE: {
6092 		int size = vcpu->arch.guest_fpu.uabi_size;
6093 
6094 		u.xsave = memdup_user(argp, size);
6095 		if (IS_ERR(u.xsave)) {
6096 			r = PTR_ERR(u.xsave);
6097 			goto out_nofree;
6098 		}
6099 
6100 		r = kvm_vcpu_ioctl_x86_set_xsave(vcpu, u.xsave);
6101 		break;
6102 	}
6103 
6104 	case KVM_GET_XSAVE2: {
6105 		int size = vcpu->arch.guest_fpu.uabi_size;
6106 
6107 		u.xsave = kzalloc(size, GFP_KERNEL_ACCOUNT);
6108 		r = -ENOMEM;
6109 		if (!u.xsave)
6110 			break;
6111 
6112 		r = kvm_vcpu_ioctl_x86_get_xsave2(vcpu, u.buffer, size);
6113 		if (r < 0)
6114 			break;
6115 
6116 		r = -EFAULT;
6117 		if (copy_to_user(argp, u.xsave, size))
6118 			break;
6119 
6120 		r = 0;
6121 		break;
6122 	}
6123 
6124 	case KVM_GET_XCRS: {
6125 		u.xcrs = kzalloc(sizeof(struct kvm_xcrs), GFP_KERNEL_ACCOUNT);
6126 		r = -ENOMEM;
6127 		if (!u.xcrs)
6128 			break;
6129 
6130 		r = kvm_vcpu_ioctl_x86_get_xcrs(vcpu, u.xcrs);
6131 		if (r < 0)
6132 			break;
6133 
6134 		r = -EFAULT;
6135 		if (copy_to_user(argp, u.xcrs,
6136 				 sizeof(struct kvm_xcrs)))
6137 			break;
6138 		r = 0;
6139 		break;
6140 	}
6141 	case KVM_SET_XCRS: {
6142 		u.xcrs = memdup_user(argp, sizeof(*u.xcrs));
6143 		if (IS_ERR(u.xcrs)) {
6144 			r = PTR_ERR(u.xcrs);
6145 			goto out_nofree;
6146 		}
6147 
6148 		r = kvm_vcpu_ioctl_x86_set_xcrs(vcpu, u.xcrs);
6149 		break;
6150 	}
6151 	case KVM_SET_TSC_KHZ: {
6152 		u32 user_tsc_khz;
6153 
6154 		r = -EINVAL;
6155 		user_tsc_khz = (u32)arg;
6156 
6157 		if (kvm_caps.has_tsc_control &&
6158 		    user_tsc_khz >= kvm_caps.max_guest_tsc_khz)
6159 			goto out;
6160 
6161 		if (user_tsc_khz == 0)
6162 			user_tsc_khz = tsc_khz;
6163 
6164 		if (!kvm_set_tsc_khz(vcpu, user_tsc_khz))
6165 			r = 0;
6166 
6167 		goto out;
6168 	}
6169 	case KVM_GET_TSC_KHZ: {
6170 		r = vcpu->arch.virtual_tsc_khz;
6171 		goto out;
6172 	}
6173 	case KVM_KVMCLOCK_CTRL: {
6174 		r = kvm_set_guest_paused(vcpu);
6175 		goto out;
6176 	}
6177 	case KVM_ENABLE_CAP: {
6178 		struct kvm_enable_cap cap;
6179 
6180 		r = -EFAULT;
6181 		if (copy_from_user(&cap, argp, sizeof(cap)))
6182 			goto out;
6183 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
6184 		break;
6185 	}
6186 	case KVM_GET_NESTED_STATE: {
6187 		struct kvm_nested_state __user *user_kvm_nested_state = argp;
6188 		u32 user_data_size;
6189 
6190 		r = -EINVAL;
6191 		if (!kvm_x86_ops.nested_ops->get_state)
6192 			break;
6193 
6194 		BUILD_BUG_ON(sizeof(user_data_size) != sizeof(user_kvm_nested_state->size));
6195 		r = -EFAULT;
6196 		if (get_user(user_data_size, &user_kvm_nested_state->size))
6197 			break;
6198 
6199 		r = kvm_x86_ops.nested_ops->get_state(vcpu, user_kvm_nested_state,
6200 						     user_data_size);
6201 		if (r < 0)
6202 			break;
6203 
6204 		if (r > user_data_size) {
6205 			if (put_user(r, &user_kvm_nested_state->size))
6206 				r = -EFAULT;
6207 			else
6208 				r = -E2BIG;
6209 			break;
6210 		}
6211 
6212 		r = 0;
6213 		break;
6214 	}
6215 	case KVM_SET_NESTED_STATE: {
6216 		struct kvm_nested_state __user *user_kvm_nested_state = argp;
6217 		struct kvm_nested_state kvm_state;
6218 		int idx;
6219 
6220 		r = -EINVAL;
6221 		if (!kvm_x86_ops.nested_ops->set_state)
6222 			break;
6223 
6224 		r = -EFAULT;
6225 		if (copy_from_user(&kvm_state, user_kvm_nested_state, sizeof(kvm_state)))
6226 			break;
6227 
6228 		r = -EINVAL;
6229 		if (kvm_state.size < sizeof(kvm_state))
6230 			break;
6231 
6232 		if (kvm_state.flags &
6233 		    ~(KVM_STATE_NESTED_RUN_PENDING | KVM_STATE_NESTED_GUEST_MODE
6234 		      | KVM_STATE_NESTED_EVMCS | KVM_STATE_NESTED_MTF_PENDING
6235 		      | KVM_STATE_NESTED_GIF_SET))
6236 			break;
6237 
6238 		/* nested_run_pending implies guest_mode.  */
6239 		if ((kvm_state.flags & KVM_STATE_NESTED_RUN_PENDING)
6240 		    && !(kvm_state.flags & KVM_STATE_NESTED_GUEST_MODE))
6241 			break;
6242 
6243 		idx = srcu_read_lock(&vcpu->kvm->srcu);
6244 		r = kvm_x86_ops.nested_ops->set_state(vcpu, user_kvm_nested_state, &kvm_state);
6245 		srcu_read_unlock(&vcpu->kvm->srcu, idx);
6246 		break;
6247 	}
6248 #ifdef CONFIG_KVM_HYPERV
6249 	case KVM_GET_SUPPORTED_HV_CPUID:
6250 		r = kvm_ioctl_get_supported_hv_cpuid(vcpu, argp);
6251 		break;
6252 #endif
6253 #ifdef CONFIG_KVM_XEN
6254 	case KVM_XEN_VCPU_GET_ATTR: {
6255 		struct kvm_xen_vcpu_attr xva;
6256 
6257 		r = -EFAULT;
6258 		if (copy_from_user(&xva, argp, sizeof(xva)))
6259 			goto out;
6260 		r = kvm_xen_vcpu_get_attr(vcpu, &xva);
6261 		if (!r && copy_to_user(argp, &xva, sizeof(xva)))
6262 			r = -EFAULT;
6263 		break;
6264 	}
6265 	case KVM_XEN_VCPU_SET_ATTR: {
6266 		struct kvm_xen_vcpu_attr xva;
6267 
6268 		r = -EFAULT;
6269 		if (copy_from_user(&xva, argp, sizeof(xva)))
6270 			goto out;
6271 		r = kvm_xen_vcpu_set_attr(vcpu, &xva);
6272 		break;
6273 	}
6274 #endif
6275 	case KVM_GET_SREGS2: {
6276 		r = -EINVAL;
6277 		if (vcpu->kvm->arch.has_protected_state &&
6278 		    vcpu->arch.guest_state_protected)
6279 			goto out;
6280 
6281 		u.sregs2 = kzalloc(sizeof(struct kvm_sregs2), GFP_KERNEL);
6282 		r = -ENOMEM;
6283 		if (!u.sregs2)
6284 			goto out;
6285 		__get_sregs2(vcpu, u.sregs2);
6286 		r = -EFAULT;
6287 		if (copy_to_user(argp, u.sregs2, sizeof(struct kvm_sregs2)))
6288 			goto out;
6289 		r = 0;
6290 		break;
6291 	}
6292 	case KVM_SET_SREGS2: {
6293 		r = -EINVAL;
6294 		if (vcpu->kvm->arch.has_protected_state &&
6295 		    vcpu->arch.guest_state_protected)
6296 			goto out;
6297 
6298 		u.sregs2 = memdup_user(argp, sizeof(struct kvm_sregs2));
6299 		if (IS_ERR(u.sregs2)) {
6300 			r = PTR_ERR(u.sregs2);
6301 			u.sregs2 = NULL;
6302 			goto out;
6303 		}
6304 		r = __set_sregs2(vcpu, u.sregs2);
6305 		break;
6306 	}
6307 	case KVM_HAS_DEVICE_ATTR:
6308 	case KVM_GET_DEVICE_ATTR:
6309 	case KVM_SET_DEVICE_ATTR:
6310 		r = kvm_vcpu_ioctl_device_attr(vcpu, ioctl, argp);
6311 		break;
6312 	default:
6313 		r = -EINVAL;
6314 	}
6315 out:
6316 	kfree(u.buffer);
6317 out_nofree:
6318 	vcpu_put(vcpu);
6319 	return r;
6320 }
6321 
kvm_arch_vcpu_fault(struct kvm_vcpu * vcpu,struct vm_fault * vmf)6322 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
6323 {
6324 	return VM_FAULT_SIGBUS;
6325 }
6326 
kvm_vm_ioctl_set_tss_addr(struct kvm * kvm,unsigned long addr)6327 static int kvm_vm_ioctl_set_tss_addr(struct kvm *kvm, unsigned long addr)
6328 {
6329 	int ret;
6330 
6331 	if (addr > (unsigned int)(-3 * PAGE_SIZE))
6332 		return -EINVAL;
6333 	ret = static_call(kvm_x86_set_tss_addr)(kvm, addr);
6334 	return ret;
6335 }
6336 
kvm_vm_ioctl_set_identity_map_addr(struct kvm * kvm,u64 ident_addr)6337 static int kvm_vm_ioctl_set_identity_map_addr(struct kvm *kvm,
6338 					      u64 ident_addr)
6339 {
6340 	return static_call(kvm_x86_set_identity_map_addr)(kvm, ident_addr);
6341 }
6342 
kvm_vm_ioctl_set_nr_mmu_pages(struct kvm * kvm,unsigned long kvm_nr_mmu_pages)6343 static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm,
6344 					 unsigned long kvm_nr_mmu_pages)
6345 {
6346 	if (kvm_nr_mmu_pages < KVM_MIN_ALLOC_MMU_PAGES)
6347 		return -EINVAL;
6348 
6349 	mutex_lock(&kvm->slots_lock);
6350 
6351 	kvm_mmu_change_mmu_pages(kvm, kvm_nr_mmu_pages);
6352 	kvm->arch.n_requested_mmu_pages = kvm_nr_mmu_pages;
6353 
6354 	mutex_unlock(&kvm->slots_lock);
6355 	return 0;
6356 }
6357 
kvm_vm_ioctl_get_irqchip(struct kvm * kvm,struct kvm_irqchip * chip)6358 static int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
6359 {
6360 	struct kvm_pic *pic = kvm->arch.vpic;
6361 	int r;
6362 
6363 	r = 0;
6364 	switch (chip->chip_id) {
6365 	case KVM_IRQCHIP_PIC_MASTER:
6366 		memcpy(&chip->chip.pic, &pic->pics[0],
6367 			sizeof(struct kvm_pic_state));
6368 		break;
6369 	case KVM_IRQCHIP_PIC_SLAVE:
6370 		memcpy(&chip->chip.pic, &pic->pics[1],
6371 			sizeof(struct kvm_pic_state));
6372 		break;
6373 	case KVM_IRQCHIP_IOAPIC:
6374 		kvm_get_ioapic(kvm, &chip->chip.ioapic);
6375 		break;
6376 	default:
6377 		r = -EINVAL;
6378 		break;
6379 	}
6380 	return r;
6381 }
6382 
kvm_vm_ioctl_set_irqchip(struct kvm * kvm,struct kvm_irqchip * chip)6383 static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
6384 {
6385 	struct kvm_pic *pic = kvm->arch.vpic;
6386 	int r;
6387 
6388 	r = 0;
6389 	switch (chip->chip_id) {
6390 	case KVM_IRQCHIP_PIC_MASTER:
6391 		spin_lock(&pic->lock);
6392 		memcpy(&pic->pics[0], &chip->chip.pic,
6393 			sizeof(struct kvm_pic_state));
6394 		spin_unlock(&pic->lock);
6395 		break;
6396 	case KVM_IRQCHIP_PIC_SLAVE:
6397 		spin_lock(&pic->lock);
6398 		memcpy(&pic->pics[1], &chip->chip.pic,
6399 			sizeof(struct kvm_pic_state));
6400 		spin_unlock(&pic->lock);
6401 		break;
6402 	case KVM_IRQCHIP_IOAPIC:
6403 		kvm_set_ioapic(kvm, &chip->chip.ioapic);
6404 		break;
6405 	default:
6406 		r = -EINVAL;
6407 		break;
6408 	}
6409 	kvm_pic_update_irq(pic);
6410 	return r;
6411 }
6412 
kvm_vm_ioctl_get_pit(struct kvm * kvm,struct kvm_pit_state * ps)6413 static int kvm_vm_ioctl_get_pit(struct kvm *kvm, struct kvm_pit_state *ps)
6414 {
6415 	struct kvm_kpit_state *kps = &kvm->arch.vpit->pit_state;
6416 
6417 	BUILD_BUG_ON(sizeof(*ps) != sizeof(kps->channels));
6418 
6419 	mutex_lock(&kps->lock);
6420 	memcpy(ps, &kps->channels, sizeof(*ps));
6421 	mutex_unlock(&kps->lock);
6422 	return 0;
6423 }
6424 
kvm_vm_ioctl_set_pit(struct kvm * kvm,struct kvm_pit_state * ps)6425 static int kvm_vm_ioctl_set_pit(struct kvm *kvm, struct kvm_pit_state *ps)
6426 {
6427 	int i;
6428 	struct kvm_pit *pit = kvm->arch.vpit;
6429 
6430 	mutex_lock(&pit->pit_state.lock);
6431 	memcpy(&pit->pit_state.channels, ps, sizeof(*ps));
6432 	for (i = 0; i < 3; i++)
6433 		kvm_pit_load_count(pit, i, ps->channels[i].count, 0);
6434 	mutex_unlock(&pit->pit_state.lock);
6435 	return 0;
6436 }
6437 
kvm_vm_ioctl_get_pit2(struct kvm * kvm,struct kvm_pit_state2 * ps)6438 static int kvm_vm_ioctl_get_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps)
6439 {
6440 	mutex_lock(&kvm->arch.vpit->pit_state.lock);
6441 	memcpy(ps->channels, &kvm->arch.vpit->pit_state.channels,
6442 		sizeof(ps->channels));
6443 	ps->flags = kvm->arch.vpit->pit_state.flags;
6444 	mutex_unlock(&kvm->arch.vpit->pit_state.lock);
6445 	memset(&ps->reserved, 0, sizeof(ps->reserved));
6446 	return 0;
6447 }
6448 
kvm_vm_ioctl_set_pit2(struct kvm * kvm,struct kvm_pit_state2 * ps)6449 static int kvm_vm_ioctl_set_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps)
6450 {
6451 	int start = 0;
6452 	int i;
6453 	u32 prev_legacy, cur_legacy;
6454 	struct kvm_pit *pit = kvm->arch.vpit;
6455 
6456 	mutex_lock(&pit->pit_state.lock);
6457 	prev_legacy = pit->pit_state.flags & KVM_PIT_FLAGS_HPET_LEGACY;
6458 	cur_legacy = ps->flags & KVM_PIT_FLAGS_HPET_LEGACY;
6459 	if (!prev_legacy && cur_legacy)
6460 		start = 1;
6461 	memcpy(&pit->pit_state.channels, &ps->channels,
6462 	       sizeof(pit->pit_state.channels));
6463 	pit->pit_state.flags = ps->flags;
6464 	for (i = 0; i < 3; i++)
6465 		kvm_pit_load_count(pit, i, pit->pit_state.channels[i].count,
6466 				   start && i == 0);
6467 	mutex_unlock(&pit->pit_state.lock);
6468 	return 0;
6469 }
6470 
kvm_vm_ioctl_reinject(struct kvm * kvm,struct kvm_reinject_control * control)6471 static int kvm_vm_ioctl_reinject(struct kvm *kvm,
6472 				 struct kvm_reinject_control *control)
6473 {
6474 	struct kvm_pit *pit = kvm->arch.vpit;
6475 
6476 	/* pit->pit_state.lock was overloaded to prevent userspace from getting
6477 	 * an inconsistent state after running multiple KVM_REINJECT_CONTROL
6478 	 * ioctls in parallel.  Use a separate lock if that ioctl isn't rare.
6479 	 */
6480 	mutex_lock(&pit->pit_state.lock);
6481 	kvm_pit_set_reinject(pit, control->pit_reinject);
6482 	mutex_unlock(&pit->pit_state.lock);
6483 
6484 	return 0;
6485 }
6486 
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)6487 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
6488 {
6489 
6490 	/*
6491 	 * Flush all CPUs' dirty log buffers to the  dirty_bitmap.  Called
6492 	 * before reporting dirty_bitmap to userspace.  KVM flushes the buffers
6493 	 * on all VM-Exits, thus we only need to kick running vCPUs to force a
6494 	 * VM-Exit.
6495 	 */
6496 	struct kvm_vcpu *vcpu;
6497 	unsigned long i;
6498 
6499 	if (!kvm_x86_ops.cpu_dirty_log_size)
6500 		return;
6501 
6502 	kvm_for_each_vcpu(i, vcpu, kvm)
6503 		kvm_vcpu_kick(vcpu);
6504 }
6505 
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_event,bool line_status)6506 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_event,
6507 			bool line_status)
6508 {
6509 	if (!irqchip_in_kernel(kvm))
6510 		return -ENXIO;
6511 
6512 	irq_event->status = kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID,
6513 					irq_event->irq, irq_event->level,
6514 					line_status);
6515 	return 0;
6516 }
6517 
kvm_vm_ioctl_enable_cap(struct kvm * kvm,struct kvm_enable_cap * cap)6518 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
6519 			    struct kvm_enable_cap *cap)
6520 {
6521 	int r;
6522 
6523 	if (cap->flags)
6524 		return -EINVAL;
6525 
6526 	switch (cap->cap) {
6527 	case KVM_CAP_DISABLE_QUIRKS2:
6528 		r = -EINVAL;
6529 		if (cap->args[0] & ~KVM_X86_VALID_QUIRKS)
6530 			break;
6531 		fallthrough;
6532 	case KVM_CAP_DISABLE_QUIRKS:
6533 		kvm->arch.disabled_quirks = cap->args[0];
6534 		r = 0;
6535 		break;
6536 	case KVM_CAP_SPLIT_IRQCHIP: {
6537 		mutex_lock(&kvm->lock);
6538 		r = -EINVAL;
6539 		if (cap->args[0] > MAX_NR_RESERVED_IOAPIC_PINS)
6540 			goto split_irqchip_unlock;
6541 		r = -EEXIST;
6542 		if (irqchip_in_kernel(kvm))
6543 			goto split_irqchip_unlock;
6544 		if (kvm->created_vcpus)
6545 			goto split_irqchip_unlock;
6546 		r = kvm_setup_empty_irq_routing(kvm);
6547 		if (r)
6548 			goto split_irqchip_unlock;
6549 		/* Pairs with irqchip_in_kernel. */
6550 		smp_wmb();
6551 		kvm->arch.irqchip_mode = KVM_IRQCHIP_SPLIT;
6552 		kvm->arch.nr_reserved_ioapic_pins = cap->args[0];
6553 		kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_ABSENT);
6554 		r = 0;
6555 split_irqchip_unlock:
6556 		mutex_unlock(&kvm->lock);
6557 		break;
6558 	}
6559 	case KVM_CAP_X2APIC_API:
6560 		r = -EINVAL;
6561 		if (cap->args[0] & ~KVM_X2APIC_API_VALID_FLAGS)
6562 			break;
6563 
6564 		if (cap->args[0] & KVM_X2APIC_API_USE_32BIT_IDS)
6565 			kvm->arch.x2apic_format = true;
6566 		if (cap->args[0] & KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK)
6567 			kvm->arch.x2apic_broadcast_quirk_disabled = true;
6568 
6569 		r = 0;
6570 		break;
6571 	case KVM_CAP_X86_DISABLE_EXITS:
6572 		r = -EINVAL;
6573 		if (cap->args[0] & ~KVM_X86_DISABLE_VALID_EXITS)
6574 			break;
6575 
6576 		if (cap->args[0] & KVM_X86_DISABLE_EXITS_PAUSE)
6577 			kvm->arch.pause_in_guest = true;
6578 
6579 #define SMT_RSB_MSG "This processor is affected by the Cross-Thread Return Predictions vulnerability. " \
6580 		    "KVM_CAP_X86_DISABLE_EXITS should only be used with SMT disabled or trusted guests."
6581 
6582 		if (!mitigate_smt_rsb) {
6583 			if (boot_cpu_has_bug(X86_BUG_SMT_RSB) && cpu_smt_possible() &&
6584 			    (cap->args[0] & ~KVM_X86_DISABLE_EXITS_PAUSE))
6585 				pr_warn_once(SMT_RSB_MSG);
6586 
6587 			if ((cap->args[0] & KVM_X86_DISABLE_EXITS_MWAIT) &&
6588 			    kvm_can_mwait_in_guest())
6589 				kvm->arch.mwait_in_guest = true;
6590 			if (cap->args[0] & KVM_X86_DISABLE_EXITS_HLT)
6591 				kvm->arch.hlt_in_guest = true;
6592 			if (cap->args[0] & KVM_X86_DISABLE_EXITS_CSTATE)
6593 				kvm->arch.cstate_in_guest = true;
6594 		}
6595 
6596 		r = 0;
6597 		break;
6598 	case KVM_CAP_MSR_PLATFORM_INFO:
6599 		kvm->arch.guest_can_read_msr_platform_info = cap->args[0];
6600 		r = 0;
6601 		break;
6602 	case KVM_CAP_EXCEPTION_PAYLOAD:
6603 		kvm->arch.exception_payload_enabled = cap->args[0];
6604 		r = 0;
6605 		break;
6606 	case KVM_CAP_X86_TRIPLE_FAULT_EVENT:
6607 		kvm->arch.triple_fault_event = cap->args[0];
6608 		r = 0;
6609 		break;
6610 	case KVM_CAP_X86_USER_SPACE_MSR:
6611 		r = -EINVAL;
6612 		if (cap->args[0] & ~KVM_MSR_EXIT_REASON_VALID_MASK)
6613 			break;
6614 		kvm->arch.user_space_msr_mask = cap->args[0];
6615 		r = 0;
6616 		break;
6617 	case KVM_CAP_X86_BUS_LOCK_EXIT:
6618 		r = -EINVAL;
6619 		if (cap->args[0] & ~KVM_BUS_LOCK_DETECTION_VALID_MODE)
6620 			break;
6621 
6622 		if ((cap->args[0] & KVM_BUS_LOCK_DETECTION_OFF) &&
6623 		    (cap->args[0] & KVM_BUS_LOCK_DETECTION_EXIT))
6624 			break;
6625 
6626 		if (kvm_caps.has_bus_lock_exit &&
6627 		    cap->args[0] & KVM_BUS_LOCK_DETECTION_EXIT)
6628 			kvm->arch.bus_lock_detection_enabled = true;
6629 		r = 0;
6630 		break;
6631 #ifdef CONFIG_X86_SGX_KVM
6632 	case KVM_CAP_SGX_ATTRIBUTE: {
6633 		unsigned long allowed_attributes = 0;
6634 
6635 		r = sgx_set_attribute(&allowed_attributes, cap->args[0]);
6636 		if (r)
6637 			break;
6638 
6639 		/* KVM only supports the PROVISIONKEY privileged attribute. */
6640 		if ((allowed_attributes & SGX_ATTR_PROVISIONKEY) &&
6641 		    !(allowed_attributes & ~SGX_ATTR_PROVISIONKEY))
6642 			kvm->arch.sgx_provisioning_allowed = true;
6643 		else
6644 			r = -EINVAL;
6645 		break;
6646 	}
6647 #endif
6648 	case KVM_CAP_VM_COPY_ENC_CONTEXT_FROM:
6649 		r = -EINVAL;
6650 		if (!kvm_x86_ops.vm_copy_enc_context_from)
6651 			break;
6652 
6653 		r = static_call(kvm_x86_vm_copy_enc_context_from)(kvm, cap->args[0]);
6654 		break;
6655 	case KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM:
6656 		r = -EINVAL;
6657 		if (!kvm_x86_ops.vm_move_enc_context_from)
6658 			break;
6659 
6660 		r = static_call(kvm_x86_vm_move_enc_context_from)(kvm, cap->args[0]);
6661 		break;
6662 	case KVM_CAP_EXIT_HYPERCALL:
6663 		if (cap->args[0] & ~KVM_EXIT_HYPERCALL_VALID_MASK) {
6664 			r = -EINVAL;
6665 			break;
6666 		}
6667 		kvm->arch.hypercall_exit_enabled = cap->args[0];
6668 		r = 0;
6669 		break;
6670 	case KVM_CAP_EXIT_ON_EMULATION_FAILURE:
6671 		r = -EINVAL;
6672 		if (cap->args[0] & ~1)
6673 			break;
6674 		kvm->arch.exit_on_emulation_error = cap->args[0];
6675 		r = 0;
6676 		break;
6677 	case KVM_CAP_PMU_CAPABILITY:
6678 		r = -EINVAL;
6679 		if (!enable_pmu || (cap->args[0] & ~KVM_CAP_PMU_VALID_MASK))
6680 			break;
6681 
6682 		mutex_lock(&kvm->lock);
6683 		if (!kvm->created_vcpus) {
6684 			kvm->arch.enable_pmu = !(cap->args[0] & KVM_PMU_CAP_DISABLE);
6685 			r = 0;
6686 		}
6687 		mutex_unlock(&kvm->lock);
6688 		break;
6689 	case KVM_CAP_MAX_VCPU_ID:
6690 		r = -EINVAL;
6691 		if (cap->args[0] > KVM_MAX_VCPU_IDS)
6692 			break;
6693 
6694 		mutex_lock(&kvm->lock);
6695 		if (kvm->arch.max_vcpu_ids == cap->args[0]) {
6696 			r = 0;
6697 		} else if (!kvm->arch.max_vcpu_ids) {
6698 			kvm->arch.max_vcpu_ids = cap->args[0];
6699 			r = 0;
6700 		}
6701 		mutex_unlock(&kvm->lock);
6702 		break;
6703 	case KVM_CAP_X86_NOTIFY_VMEXIT:
6704 		r = -EINVAL;
6705 		if ((u32)cap->args[0] & ~KVM_X86_NOTIFY_VMEXIT_VALID_BITS)
6706 			break;
6707 		if (!kvm_caps.has_notify_vmexit)
6708 			break;
6709 		if (!((u32)cap->args[0] & KVM_X86_NOTIFY_VMEXIT_ENABLED))
6710 			break;
6711 		mutex_lock(&kvm->lock);
6712 		if (!kvm->created_vcpus) {
6713 			kvm->arch.notify_window = cap->args[0] >> 32;
6714 			kvm->arch.notify_vmexit_flags = (u32)cap->args[0];
6715 			r = 0;
6716 		}
6717 		mutex_unlock(&kvm->lock);
6718 		break;
6719 	case KVM_CAP_VM_DISABLE_NX_HUGE_PAGES:
6720 		r = -EINVAL;
6721 
6722 		/*
6723 		 * Since the risk of disabling NX hugepages is a guest crashing
6724 		 * the system, ensure the userspace process has permission to
6725 		 * reboot the system.
6726 		 *
6727 		 * Note that unlike the reboot() syscall, the process must have
6728 		 * this capability in the root namespace because exposing
6729 		 * /dev/kvm into a container does not limit the scope of the
6730 		 * iTLB multihit bug to that container. In other words,
6731 		 * this must use capable(), not ns_capable().
6732 		 */
6733 		if (!capable(CAP_SYS_BOOT)) {
6734 			r = -EPERM;
6735 			break;
6736 		}
6737 
6738 		if (cap->args[0])
6739 			break;
6740 
6741 		mutex_lock(&kvm->lock);
6742 		if (!kvm->created_vcpus) {
6743 			kvm->arch.disable_nx_huge_pages = true;
6744 			r = 0;
6745 		}
6746 		mutex_unlock(&kvm->lock);
6747 		break;
6748 	default:
6749 		r = -EINVAL;
6750 		break;
6751 	}
6752 	return r;
6753 }
6754 
kvm_alloc_msr_filter(bool default_allow)6755 static struct kvm_x86_msr_filter *kvm_alloc_msr_filter(bool default_allow)
6756 {
6757 	struct kvm_x86_msr_filter *msr_filter;
6758 
6759 	msr_filter = kzalloc(sizeof(*msr_filter), GFP_KERNEL_ACCOUNT);
6760 	if (!msr_filter)
6761 		return NULL;
6762 
6763 	msr_filter->default_allow = default_allow;
6764 	return msr_filter;
6765 }
6766 
kvm_free_msr_filter(struct kvm_x86_msr_filter * msr_filter)6767 static void kvm_free_msr_filter(struct kvm_x86_msr_filter *msr_filter)
6768 {
6769 	u32 i;
6770 
6771 	if (!msr_filter)
6772 		return;
6773 
6774 	for (i = 0; i < msr_filter->count; i++)
6775 		kfree(msr_filter->ranges[i].bitmap);
6776 
6777 	kfree(msr_filter);
6778 }
6779 
kvm_add_msr_filter(struct kvm_x86_msr_filter * msr_filter,struct kvm_msr_filter_range * user_range)6780 static int kvm_add_msr_filter(struct kvm_x86_msr_filter *msr_filter,
6781 			      struct kvm_msr_filter_range *user_range)
6782 {
6783 	unsigned long *bitmap;
6784 	size_t bitmap_size;
6785 
6786 	if (!user_range->nmsrs)
6787 		return 0;
6788 
6789 	if (user_range->flags & ~KVM_MSR_FILTER_RANGE_VALID_MASK)
6790 		return -EINVAL;
6791 
6792 	if (!user_range->flags)
6793 		return -EINVAL;
6794 
6795 	bitmap_size = BITS_TO_LONGS(user_range->nmsrs) * sizeof(long);
6796 	if (!bitmap_size || bitmap_size > KVM_MSR_FILTER_MAX_BITMAP_SIZE)
6797 		return -EINVAL;
6798 
6799 	bitmap = memdup_user((__user u8*)user_range->bitmap, bitmap_size);
6800 	if (IS_ERR(bitmap))
6801 		return PTR_ERR(bitmap);
6802 
6803 	msr_filter->ranges[msr_filter->count] = (struct msr_bitmap_range) {
6804 		.flags = user_range->flags,
6805 		.base = user_range->base,
6806 		.nmsrs = user_range->nmsrs,
6807 		.bitmap = bitmap,
6808 	};
6809 
6810 	msr_filter->count++;
6811 	return 0;
6812 }
6813 
kvm_vm_ioctl_set_msr_filter(struct kvm * kvm,struct kvm_msr_filter * filter)6814 static int kvm_vm_ioctl_set_msr_filter(struct kvm *kvm,
6815 				       struct kvm_msr_filter *filter)
6816 {
6817 	struct kvm_x86_msr_filter *new_filter, *old_filter;
6818 	bool default_allow;
6819 	bool empty = true;
6820 	int r;
6821 	u32 i;
6822 
6823 	if (filter->flags & ~KVM_MSR_FILTER_VALID_MASK)
6824 		return -EINVAL;
6825 
6826 	for (i = 0; i < ARRAY_SIZE(filter->ranges); i++)
6827 		empty &= !filter->ranges[i].nmsrs;
6828 
6829 	default_allow = !(filter->flags & KVM_MSR_FILTER_DEFAULT_DENY);
6830 	if (empty && !default_allow)
6831 		return -EINVAL;
6832 
6833 	new_filter = kvm_alloc_msr_filter(default_allow);
6834 	if (!new_filter)
6835 		return -ENOMEM;
6836 
6837 	for (i = 0; i < ARRAY_SIZE(filter->ranges); i++) {
6838 		r = kvm_add_msr_filter(new_filter, &filter->ranges[i]);
6839 		if (r) {
6840 			kvm_free_msr_filter(new_filter);
6841 			return r;
6842 		}
6843 	}
6844 
6845 	mutex_lock(&kvm->lock);
6846 	old_filter = rcu_replace_pointer(kvm->arch.msr_filter, new_filter,
6847 					 mutex_is_locked(&kvm->lock));
6848 	mutex_unlock(&kvm->lock);
6849 	synchronize_srcu(&kvm->srcu);
6850 
6851 	kvm_free_msr_filter(old_filter);
6852 
6853 	kvm_make_all_cpus_request(kvm, KVM_REQ_MSR_FILTER_CHANGED);
6854 
6855 	return 0;
6856 }
6857 
6858 #ifdef CONFIG_KVM_COMPAT
6859 /* for KVM_X86_SET_MSR_FILTER */
6860 struct kvm_msr_filter_range_compat {
6861 	__u32 flags;
6862 	__u32 nmsrs;
6863 	__u32 base;
6864 	__u32 bitmap;
6865 };
6866 
6867 struct kvm_msr_filter_compat {
6868 	__u32 flags;
6869 	struct kvm_msr_filter_range_compat ranges[KVM_MSR_FILTER_MAX_RANGES];
6870 };
6871 
6872 #define KVM_X86_SET_MSR_FILTER_COMPAT _IOW(KVMIO, 0xc6, struct kvm_msr_filter_compat)
6873 
kvm_arch_vm_compat_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)6874 long kvm_arch_vm_compat_ioctl(struct file *filp, unsigned int ioctl,
6875 			      unsigned long arg)
6876 {
6877 	void __user *argp = (void __user *)arg;
6878 	struct kvm *kvm = filp->private_data;
6879 	long r = -ENOTTY;
6880 
6881 	switch (ioctl) {
6882 	case KVM_X86_SET_MSR_FILTER_COMPAT: {
6883 		struct kvm_msr_filter __user *user_msr_filter = argp;
6884 		struct kvm_msr_filter_compat filter_compat;
6885 		struct kvm_msr_filter filter;
6886 		int i;
6887 
6888 		if (copy_from_user(&filter_compat, user_msr_filter,
6889 				   sizeof(filter_compat)))
6890 			return -EFAULT;
6891 
6892 		filter.flags = filter_compat.flags;
6893 		for (i = 0; i < ARRAY_SIZE(filter.ranges); i++) {
6894 			struct kvm_msr_filter_range_compat *cr;
6895 
6896 			cr = &filter_compat.ranges[i];
6897 			filter.ranges[i] = (struct kvm_msr_filter_range) {
6898 				.flags = cr->flags,
6899 				.nmsrs = cr->nmsrs,
6900 				.base = cr->base,
6901 				.bitmap = (__u8 *)(ulong)cr->bitmap,
6902 			};
6903 		}
6904 
6905 		r = kvm_vm_ioctl_set_msr_filter(kvm, &filter);
6906 		break;
6907 	}
6908 	}
6909 
6910 	return r;
6911 }
6912 #endif
6913 
6914 #ifdef CONFIG_HAVE_KVM_PM_NOTIFIER
kvm_arch_suspend_notifier(struct kvm * kvm)6915 static int kvm_arch_suspend_notifier(struct kvm *kvm)
6916 {
6917 	struct kvm_vcpu *vcpu;
6918 	unsigned long i;
6919 	int ret = 0;
6920 
6921 	mutex_lock(&kvm->lock);
6922 	kvm_for_each_vcpu(i, vcpu, kvm) {
6923 		if (!vcpu->arch.pv_time.active)
6924 			continue;
6925 
6926 		ret = kvm_set_guest_paused(vcpu);
6927 		if (ret) {
6928 			kvm_err("Failed to pause guest VCPU%d: %d\n",
6929 				vcpu->vcpu_id, ret);
6930 			break;
6931 		}
6932 	}
6933 	mutex_unlock(&kvm->lock);
6934 
6935 	return ret ? NOTIFY_BAD : NOTIFY_DONE;
6936 }
6937 
kvm_arch_pm_notifier(struct kvm * kvm,unsigned long state)6938 int kvm_arch_pm_notifier(struct kvm *kvm, unsigned long state)
6939 {
6940 	switch (state) {
6941 	case PM_HIBERNATION_PREPARE:
6942 	case PM_SUSPEND_PREPARE:
6943 		return kvm_arch_suspend_notifier(kvm);
6944 	}
6945 
6946 	return NOTIFY_DONE;
6947 }
6948 #endif /* CONFIG_HAVE_KVM_PM_NOTIFIER */
6949 
kvm_vm_ioctl_get_clock(struct kvm * kvm,void __user * argp)6950 static int kvm_vm_ioctl_get_clock(struct kvm *kvm, void __user *argp)
6951 {
6952 	struct kvm_clock_data data = { 0 };
6953 
6954 	get_kvmclock(kvm, &data);
6955 	if (copy_to_user(argp, &data, sizeof(data)))
6956 		return -EFAULT;
6957 
6958 	return 0;
6959 }
6960 
kvm_vm_ioctl_set_clock(struct kvm * kvm,void __user * argp)6961 static int kvm_vm_ioctl_set_clock(struct kvm *kvm, void __user *argp)
6962 {
6963 	struct kvm_arch *ka = &kvm->arch;
6964 	struct kvm_clock_data data;
6965 	u64 now_raw_ns;
6966 
6967 	if (copy_from_user(&data, argp, sizeof(data)))
6968 		return -EFAULT;
6969 
6970 	/*
6971 	 * Only KVM_CLOCK_REALTIME is used, but allow passing the
6972 	 * result of KVM_GET_CLOCK back to KVM_SET_CLOCK.
6973 	 */
6974 	if (data.flags & ~KVM_CLOCK_VALID_FLAGS)
6975 		return -EINVAL;
6976 
6977 	kvm_hv_request_tsc_page_update(kvm);
6978 	kvm_start_pvclock_update(kvm);
6979 	pvclock_update_vm_gtod_copy(kvm);
6980 
6981 	/*
6982 	 * This pairs with kvm_guest_time_update(): when masterclock is
6983 	 * in use, we use master_kernel_ns + kvmclock_offset to set
6984 	 * unsigned 'system_time' so if we use get_kvmclock_ns() (which
6985 	 * is slightly ahead) here we risk going negative on unsigned
6986 	 * 'system_time' when 'data.clock' is very small.
6987 	 */
6988 	if (data.flags & KVM_CLOCK_REALTIME) {
6989 		u64 now_real_ns = ktime_get_real_ns();
6990 
6991 		/*
6992 		 * Avoid stepping the kvmclock backwards.
6993 		 */
6994 		if (now_real_ns > data.realtime)
6995 			data.clock += now_real_ns - data.realtime;
6996 	}
6997 
6998 	if (ka->use_master_clock)
6999 		now_raw_ns = ka->master_kernel_ns;
7000 	else
7001 		now_raw_ns = get_kvmclock_base_ns();
7002 	ka->kvmclock_offset = data.clock - now_raw_ns;
7003 	kvm_end_pvclock_update(kvm);
7004 	return 0;
7005 }
7006 
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)7007 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
7008 {
7009 	struct kvm *kvm = filp->private_data;
7010 	void __user *argp = (void __user *)arg;
7011 	int r = -ENOTTY;
7012 	/*
7013 	 * This union makes it completely explicit to gcc-3.x
7014 	 * that these two variables' stack usage should be
7015 	 * combined, not added together.
7016 	 */
7017 	union {
7018 		struct kvm_pit_state ps;
7019 		struct kvm_pit_state2 ps2;
7020 		struct kvm_pit_config pit_config;
7021 	} u;
7022 
7023 	switch (ioctl) {
7024 	case KVM_SET_TSS_ADDR:
7025 		r = kvm_vm_ioctl_set_tss_addr(kvm, arg);
7026 		break;
7027 	case KVM_SET_IDENTITY_MAP_ADDR: {
7028 		u64 ident_addr;
7029 
7030 		mutex_lock(&kvm->lock);
7031 		r = -EINVAL;
7032 		if (kvm->created_vcpus)
7033 			goto set_identity_unlock;
7034 		r = -EFAULT;
7035 		if (copy_from_user(&ident_addr, argp, sizeof(ident_addr)))
7036 			goto set_identity_unlock;
7037 		r = kvm_vm_ioctl_set_identity_map_addr(kvm, ident_addr);
7038 set_identity_unlock:
7039 		mutex_unlock(&kvm->lock);
7040 		break;
7041 	}
7042 	case KVM_SET_NR_MMU_PAGES:
7043 		r = kvm_vm_ioctl_set_nr_mmu_pages(kvm, arg);
7044 		break;
7045 	case KVM_CREATE_IRQCHIP: {
7046 		mutex_lock(&kvm->lock);
7047 
7048 		r = -EEXIST;
7049 		if (irqchip_in_kernel(kvm))
7050 			goto create_irqchip_unlock;
7051 
7052 		r = -EINVAL;
7053 		if (kvm->created_vcpus)
7054 			goto create_irqchip_unlock;
7055 
7056 		r = kvm_pic_init(kvm);
7057 		if (r)
7058 			goto create_irqchip_unlock;
7059 
7060 		r = kvm_ioapic_init(kvm);
7061 		if (r) {
7062 			kvm_pic_destroy(kvm);
7063 			goto create_irqchip_unlock;
7064 		}
7065 
7066 		r = kvm_setup_default_irq_routing(kvm);
7067 		if (r) {
7068 			kvm_ioapic_destroy(kvm);
7069 			kvm_pic_destroy(kvm);
7070 			goto create_irqchip_unlock;
7071 		}
7072 		/* Write kvm->irq_routing before enabling irqchip_in_kernel. */
7073 		smp_wmb();
7074 		kvm->arch.irqchip_mode = KVM_IRQCHIP_KERNEL;
7075 		kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_ABSENT);
7076 	create_irqchip_unlock:
7077 		mutex_unlock(&kvm->lock);
7078 		break;
7079 	}
7080 	case KVM_CREATE_PIT:
7081 		u.pit_config.flags = KVM_PIT_SPEAKER_DUMMY;
7082 		goto create_pit;
7083 	case KVM_CREATE_PIT2:
7084 		r = -EFAULT;
7085 		if (copy_from_user(&u.pit_config, argp,
7086 				   sizeof(struct kvm_pit_config)))
7087 			goto out;
7088 	create_pit:
7089 		mutex_lock(&kvm->lock);
7090 		r = -EEXIST;
7091 		if (kvm->arch.vpit)
7092 			goto create_pit_unlock;
7093 		r = -ENOENT;
7094 		if (!pic_in_kernel(kvm))
7095 			goto create_pit_unlock;
7096 		r = -ENOMEM;
7097 		kvm->arch.vpit = kvm_create_pit(kvm, u.pit_config.flags);
7098 		if (kvm->arch.vpit)
7099 			r = 0;
7100 	create_pit_unlock:
7101 		mutex_unlock(&kvm->lock);
7102 		break;
7103 	case KVM_GET_IRQCHIP: {
7104 		/* 0: PIC master, 1: PIC slave, 2: IOAPIC */
7105 		struct kvm_irqchip *chip;
7106 
7107 		chip = memdup_user(argp, sizeof(*chip));
7108 		if (IS_ERR(chip)) {
7109 			r = PTR_ERR(chip);
7110 			goto out;
7111 		}
7112 
7113 		r = -ENXIO;
7114 		if (!irqchip_kernel(kvm))
7115 			goto get_irqchip_out;
7116 		r = kvm_vm_ioctl_get_irqchip(kvm, chip);
7117 		if (r)
7118 			goto get_irqchip_out;
7119 		r = -EFAULT;
7120 		if (copy_to_user(argp, chip, sizeof(*chip)))
7121 			goto get_irqchip_out;
7122 		r = 0;
7123 	get_irqchip_out:
7124 		kfree(chip);
7125 		break;
7126 	}
7127 	case KVM_SET_IRQCHIP: {
7128 		/* 0: PIC master, 1: PIC slave, 2: IOAPIC */
7129 		struct kvm_irqchip *chip;
7130 
7131 		chip = memdup_user(argp, sizeof(*chip));
7132 		if (IS_ERR(chip)) {
7133 			r = PTR_ERR(chip);
7134 			goto out;
7135 		}
7136 
7137 		r = -ENXIO;
7138 		if (!irqchip_kernel(kvm))
7139 			goto set_irqchip_out;
7140 		r = kvm_vm_ioctl_set_irqchip(kvm, chip);
7141 	set_irqchip_out:
7142 		kfree(chip);
7143 		break;
7144 	}
7145 	case KVM_GET_PIT: {
7146 		r = -EFAULT;
7147 		if (copy_from_user(&u.ps, argp, sizeof(struct kvm_pit_state)))
7148 			goto out;
7149 		r = -ENXIO;
7150 		if (!kvm->arch.vpit)
7151 			goto out;
7152 		r = kvm_vm_ioctl_get_pit(kvm, &u.ps);
7153 		if (r)
7154 			goto out;
7155 		r = -EFAULT;
7156 		if (copy_to_user(argp, &u.ps, sizeof(struct kvm_pit_state)))
7157 			goto out;
7158 		r = 0;
7159 		break;
7160 	}
7161 	case KVM_SET_PIT: {
7162 		r = -EFAULT;
7163 		if (copy_from_user(&u.ps, argp, sizeof(u.ps)))
7164 			goto out;
7165 		mutex_lock(&kvm->lock);
7166 		r = -ENXIO;
7167 		if (!kvm->arch.vpit)
7168 			goto set_pit_out;
7169 		r = kvm_vm_ioctl_set_pit(kvm, &u.ps);
7170 set_pit_out:
7171 		mutex_unlock(&kvm->lock);
7172 		break;
7173 	}
7174 	case KVM_GET_PIT2: {
7175 		r = -ENXIO;
7176 		if (!kvm->arch.vpit)
7177 			goto out;
7178 		r = kvm_vm_ioctl_get_pit2(kvm, &u.ps2);
7179 		if (r)
7180 			goto out;
7181 		r = -EFAULT;
7182 		if (copy_to_user(argp, &u.ps2, sizeof(u.ps2)))
7183 			goto out;
7184 		r = 0;
7185 		break;
7186 	}
7187 	case KVM_SET_PIT2: {
7188 		r = -EFAULT;
7189 		if (copy_from_user(&u.ps2, argp, sizeof(u.ps2)))
7190 			goto out;
7191 		mutex_lock(&kvm->lock);
7192 		r = -ENXIO;
7193 		if (!kvm->arch.vpit)
7194 			goto set_pit2_out;
7195 		r = kvm_vm_ioctl_set_pit2(kvm, &u.ps2);
7196 set_pit2_out:
7197 		mutex_unlock(&kvm->lock);
7198 		break;
7199 	}
7200 	case KVM_REINJECT_CONTROL: {
7201 		struct kvm_reinject_control control;
7202 		r =  -EFAULT;
7203 		if (copy_from_user(&control, argp, sizeof(control)))
7204 			goto out;
7205 		r = -ENXIO;
7206 		if (!kvm->arch.vpit)
7207 			goto out;
7208 		r = kvm_vm_ioctl_reinject(kvm, &control);
7209 		break;
7210 	}
7211 	case KVM_SET_BOOT_CPU_ID:
7212 		r = 0;
7213 		mutex_lock(&kvm->lock);
7214 		if (kvm->created_vcpus)
7215 			r = -EBUSY;
7216 		else
7217 			kvm->arch.bsp_vcpu_id = arg;
7218 		mutex_unlock(&kvm->lock);
7219 		break;
7220 #ifdef CONFIG_KVM_XEN
7221 	case KVM_XEN_HVM_CONFIG: {
7222 		struct kvm_xen_hvm_config xhc;
7223 		r = -EFAULT;
7224 		if (copy_from_user(&xhc, argp, sizeof(xhc)))
7225 			goto out;
7226 		r = kvm_xen_hvm_config(kvm, &xhc);
7227 		break;
7228 	}
7229 	case KVM_XEN_HVM_GET_ATTR: {
7230 		struct kvm_xen_hvm_attr xha;
7231 
7232 		r = -EFAULT;
7233 		if (copy_from_user(&xha, argp, sizeof(xha)))
7234 			goto out;
7235 		r = kvm_xen_hvm_get_attr(kvm, &xha);
7236 		if (!r && copy_to_user(argp, &xha, sizeof(xha)))
7237 			r = -EFAULT;
7238 		break;
7239 	}
7240 	case KVM_XEN_HVM_SET_ATTR: {
7241 		struct kvm_xen_hvm_attr xha;
7242 
7243 		r = -EFAULT;
7244 		if (copy_from_user(&xha, argp, sizeof(xha)))
7245 			goto out;
7246 		r = kvm_xen_hvm_set_attr(kvm, &xha);
7247 		break;
7248 	}
7249 	case KVM_XEN_HVM_EVTCHN_SEND: {
7250 		struct kvm_irq_routing_xen_evtchn uxe;
7251 
7252 		r = -EFAULT;
7253 		if (copy_from_user(&uxe, argp, sizeof(uxe)))
7254 			goto out;
7255 		r = kvm_xen_hvm_evtchn_send(kvm, &uxe);
7256 		break;
7257 	}
7258 #endif
7259 	case KVM_SET_CLOCK:
7260 		r = kvm_vm_ioctl_set_clock(kvm, argp);
7261 		break;
7262 	case KVM_GET_CLOCK:
7263 		r = kvm_vm_ioctl_get_clock(kvm, argp);
7264 		break;
7265 	case KVM_SET_TSC_KHZ: {
7266 		u32 user_tsc_khz;
7267 
7268 		r = -EINVAL;
7269 		user_tsc_khz = (u32)arg;
7270 
7271 		if (kvm_caps.has_tsc_control &&
7272 		    user_tsc_khz >= kvm_caps.max_guest_tsc_khz)
7273 			goto out;
7274 
7275 		if (user_tsc_khz == 0)
7276 			user_tsc_khz = tsc_khz;
7277 
7278 		WRITE_ONCE(kvm->arch.default_tsc_khz, user_tsc_khz);
7279 		r = 0;
7280 
7281 		goto out;
7282 	}
7283 	case KVM_GET_TSC_KHZ: {
7284 		r = READ_ONCE(kvm->arch.default_tsc_khz);
7285 		goto out;
7286 	}
7287 	case KVM_MEMORY_ENCRYPT_OP: {
7288 		r = -ENOTTY;
7289 		if (!kvm_x86_ops.mem_enc_ioctl)
7290 			goto out;
7291 
7292 		r = static_call(kvm_x86_mem_enc_ioctl)(kvm, argp);
7293 		break;
7294 	}
7295 	case KVM_MEMORY_ENCRYPT_REG_REGION: {
7296 		struct kvm_enc_region region;
7297 
7298 		r = -EFAULT;
7299 		if (copy_from_user(&region, argp, sizeof(region)))
7300 			goto out;
7301 
7302 		r = -ENOTTY;
7303 		if (!kvm_x86_ops.mem_enc_register_region)
7304 			goto out;
7305 
7306 		r = static_call(kvm_x86_mem_enc_register_region)(kvm, &region);
7307 		break;
7308 	}
7309 	case KVM_MEMORY_ENCRYPT_UNREG_REGION: {
7310 		struct kvm_enc_region region;
7311 
7312 		r = -EFAULT;
7313 		if (copy_from_user(&region, argp, sizeof(region)))
7314 			goto out;
7315 
7316 		r = -ENOTTY;
7317 		if (!kvm_x86_ops.mem_enc_unregister_region)
7318 			goto out;
7319 
7320 		r = static_call(kvm_x86_mem_enc_unregister_region)(kvm, &region);
7321 		break;
7322 	}
7323 #ifdef CONFIG_KVM_HYPERV
7324 	case KVM_HYPERV_EVENTFD: {
7325 		struct kvm_hyperv_eventfd hvevfd;
7326 
7327 		r = -EFAULT;
7328 		if (copy_from_user(&hvevfd, argp, sizeof(hvevfd)))
7329 			goto out;
7330 		r = kvm_vm_ioctl_hv_eventfd(kvm, &hvevfd);
7331 		break;
7332 	}
7333 #endif
7334 	case KVM_SET_PMU_EVENT_FILTER:
7335 		r = kvm_vm_ioctl_set_pmu_event_filter(kvm, argp);
7336 		break;
7337 	case KVM_X86_SET_MSR_FILTER: {
7338 		struct kvm_msr_filter __user *user_msr_filter = argp;
7339 		struct kvm_msr_filter filter;
7340 
7341 		if (copy_from_user(&filter, user_msr_filter, sizeof(filter)))
7342 			return -EFAULT;
7343 
7344 		r = kvm_vm_ioctl_set_msr_filter(kvm, &filter);
7345 		break;
7346 	}
7347 	default:
7348 		r = -ENOTTY;
7349 	}
7350 out:
7351 	return r;
7352 }
7353 
kvm_probe_feature_msr(u32 msr_index)7354 static void kvm_probe_feature_msr(u32 msr_index)
7355 {
7356 	struct kvm_msr_entry msr = {
7357 		.index = msr_index,
7358 	};
7359 
7360 	if (kvm_get_msr_feature(&msr))
7361 		return;
7362 
7363 	msr_based_features[num_msr_based_features++] = msr_index;
7364 }
7365 
kvm_probe_msr_to_save(u32 msr_index)7366 static void kvm_probe_msr_to_save(u32 msr_index)
7367 {
7368 	u32 dummy[2];
7369 
7370 	if (rdmsr_safe(msr_index, &dummy[0], &dummy[1]))
7371 		return;
7372 
7373 	/*
7374 	 * Even MSRs that are valid in the host may not be exposed to guests in
7375 	 * some cases.
7376 	 */
7377 	switch (msr_index) {
7378 	case MSR_IA32_BNDCFGS:
7379 		if (!kvm_mpx_supported())
7380 			return;
7381 		break;
7382 	case MSR_TSC_AUX:
7383 		if (!kvm_cpu_cap_has(X86_FEATURE_RDTSCP) &&
7384 		    !kvm_cpu_cap_has(X86_FEATURE_RDPID))
7385 			return;
7386 		break;
7387 	case MSR_IA32_UMWAIT_CONTROL:
7388 		if (!kvm_cpu_cap_has(X86_FEATURE_WAITPKG))
7389 			return;
7390 		break;
7391 	case MSR_IA32_RTIT_CTL:
7392 	case MSR_IA32_RTIT_STATUS:
7393 		if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT))
7394 			return;
7395 		break;
7396 	case MSR_IA32_RTIT_CR3_MATCH:
7397 		if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT) ||
7398 		    !intel_pt_validate_hw_cap(PT_CAP_cr3_filtering))
7399 			return;
7400 		break;
7401 	case MSR_IA32_RTIT_OUTPUT_BASE:
7402 	case MSR_IA32_RTIT_OUTPUT_MASK:
7403 		if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT) ||
7404 		    (!intel_pt_validate_hw_cap(PT_CAP_topa_output) &&
7405 		     !intel_pt_validate_hw_cap(PT_CAP_single_range_output)))
7406 			return;
7407 		break;
7408 	case MSR_IA32_RTIT_ADDR0_A ... MSR_IA32_RTIT_ADDR3_B:
7409 		if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT) ||
7410 		    (msr_index - MSR_IA32_RTIT_ADDR0_A >=
7411 		     intel_pt_validate_hw_cap(PT_CAP_num_address_ranges) * 2))
7412 			return;
7413 		break;
7414 	case MSR_ARCH_PERFMON_PERFCTR0 ... MSR_ARCH_PERFMON_PERFCTR_MAX:
7415 		if (msr_index - MSR_ARCH_PERFMON_PERFCTR0 >=
7416 		    kvm_pmu_cap.num_counters_gp)
7417 			return;
7418 		break;
7419 	case MSR_ARCH_PERFMON_EVENTSEL0 ... MSR_ARCH_PERFMON_EVENTSEL_MAX:
7420 		if (msr_index - MSR_ARCH_PERFMON_EVENTSEL0 >=
7421 		    kvm_pmu_cap.num_counters_gp)
7422 			return;
7423 		break;
7424 	case MSR_ARCH_PERFMON_FIXED_CTR0 ... MSR_ARCH_PERFMON_FIXED_CTR_MAX:
7425 		if (msr_index - MSR_ARCH_PERFMON_FIXED_CTR0 >=
7426 		    kvm_pmu_cap.num_counters_fixed)
7427 			return;
7428 		break;
7429 	case MSR_AMD64_PERF_CNTR_GLOBAL_CTL:
7430 	case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS:
7431 	case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR:
7432 		if (!kvm_cpu_cap_has(X86_FEATURE_PERFMON_V2))
7433 			return;
7434 		break;
7435 	case MSR_IA32_XFD:
7436 	case MSR_IA32_XFD_ERR:
7437 		if (!kvm_cpu_cap_has(X86_FEATURE_XFD))
7438 			return;
7439 		break;
7440 	case MSR_IA32_TSX_CTRL:
7441 		if (!(kvm_get_arch_capabilities() & ARCH_CAP_TSX_CTRL_MSR))
7442 			return;
7443 		break;
7444 	default:
7445 		break;
7446 	}
7447 
7448 	msrs_to_save[num_msrs_to_save++] = msr_index;
7449 }
7450 
kvm_init_msr_lists(void)7451 static void kvm_init_msr_lists(void)
7452 {
7453 	unsigned i;
7454 
7455 	BUILD_BUG_ON_MSG(KVM_PMC_MAX_FIXED != 3,
7456 			 "Please update the fixed PMCs in msrs_to_save_pmu[]");
7457 
7458 	num_msrs_to_save = 0;
7459 	num_emulated_msrs = 0;
7460 	num_msr_based_features = 0;
7461 
7462 	for (i = 0; i < ARRAY_SIZE(msrs_to_save_base); i++)
7463 		kvm_probe_msr_to_save(msrs_to_save_base[i]);
7464 
7465 	if (enable_pmu) {
7466 		for (i = 0; i < ARRAY_SIZE(msrs_to_save_pmu); i++)
7467 			kvm_probe_msr_to_save(msrs_to_save_pmu[i]);
7468 	}
7469 
7470 	for (i = 0; i < ARRAY_SIZE(emulated_msrs_all); i++) {
7471 		if (!static_call(kvm_x86_has_emulated_msr)(NULL, emulated_msrs_all[i]))
7472 			continue;
7473 
7474 		emulated_msrs[num_emulated_msrs++] = emulated_msrs_all[i];
7475 	}
7476 
7477 	for (i = KVM_FIRST_EMULATED_VMX_MSR; i <= KVM_LAST_EMULATED_VMX_MSR; i++)
7478 		kvm_probe_feature_msr(i);
7479 
7480 	for (i = 0; i < ARRAY_SIZE(msr_based_features_all_except_vmx); i++)
7481 		kvm_probe_feature_msr(msr_based_features_all_except_vmx[i]);
7482 }
7483 
vcpu_mmio_write(struct kvm_vcpu * vcpu,gpa_t addr,int len,const void * v)7484 static int vcpu_mmio_write(struct kvm_vcpu *vcpu, gpa_t addr, int len,
7485 			   const void *v)
7486 {
7487 	int handled = 0;
7488 	int n;
7489 
7490 	do {
7491 		n = min(len, 8);
7492 		if (!(lapic_in_kernel(vcpu) &&
7493 		      !kvm_iodevice_write(vcpu, &vcpu->arch.apic->dev, addr, n, v))
7494 		    && kvm_io_bus_write(vcpu, KVM_MMIO_BUS, addr, n, v))
7495 			break;
7496 		handled += n;
7497 		addr += n;
7498 		len -= n;
7499 		v += n;
7500 	} while (len);
7501 
7502 	return handled;
7503 }
7504 
vcpu_mmio_read(struct kvm_vcpu * vcpu,gpa_t addr,int len,void * v)7505 static int vcpu_mmio_read(struct kvm_vcpu *vcpu, gpa_t addr, int len, void *v)
7506 {
7507 	int handled = 0;
7508 	int n;
7509 
7510 	do {
7511 		n = min(len, 8);
7512 		if (!(lapic_in_kernel(vcpu) &&
7513 		      !kvm_iodevice_read(vcpu, &vcpu->arch.apic->dev,
7514 					 addr, n, v))
7515 		    && kvm_io_bus_read(vcpu, KVM_MMIO_BUS, addr, n, v))
7516 			break;
7517 		trace_kvm_mmio(KVM_TRACE_MMIO_READ, n, addr, v);
7518 		handled += n;
7519 		addr += n;
7520 		len -= n;
7521 		v += n;
7522 	} while (len);
7523 
7524 	return handled;
7525 }
7526 
kvm_set_segment(struct kvm_vcpu * vcpu,struct kvm_segment * var,int seg)7527 void kvm_set_segment(struct kvm_vcpu *vcpu,
7528 		     struct kvm_segment *var, int seg)
7529 {
7530 	static_call(kvm_x86_set_segment)(vcpu, var, seg);
7531 }
7532 
kvm_get_segment(struct kvm_vcpu * vcpu,struct kvm_segment * var,int seg)7533 void kvm_get_segment(struct kvm_vcpu *vcpu,
7534 		     struct kvm_segment *var, int seg)
7535 {
7536 	static_call(kvm_x86_get_segment)(vcpu, var, seg);
7537 }
7538 
translate_nested_gpa(struct kvm_vcpu * vcpu,gpa_t gpa,u64 access,struct x86_exception * exception)7539 gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u64 access,
7540 			   struct x86_exception *exception)
7541 {
7542 	struct kvm_mmu *mmu = vcpu->arch.mmu;
7543 	gpa_t t_gpa;
7544 
7545 	BUG_ON(!mmu_is_nested(vcpu));
7546 
7547 	/* NPT walks are always user-walks */
7548 	access |= PFERR_USER_MASK;
7549 	t_gpa  = mmu->gva_to_gpa(vcpu, mmu, gpa, access, exception);
7550 
7551 	return t_gpa;
7552 }
7553 
kvm_mmu_gva_to_gpa_read(struct kvm_vcpu * vcpu,gva_t gva,struct x86_exception * exception)7554 gpa_t kvm_mmu_gva_to_gpa_read(struct kvm_vcpu *vcpu, gva_t gva,
7555 			      struct x86_exception *exception)
7556 {
7557 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7558 
7559 	u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
7560 	return mmu->gva_to_gpa(vcpu, mmu, gva, access, exception);
7561 }
7562 EXPORT_SYMBOL_GPL(kvm_mmu_gva_to_gpa_read);
7563 
kvm_mmu_gva_to_gpa_write(struct kvm_vcpu * vcpu,gva_t gva,struct x86_exception * exception)7564 gpa_t kvm_mmu_gva_to_gpa_write(struct kvm_vcpu *vcpu, gva_t gva,
7565 			       struct x86_exception *exception)
7566 {
7567 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7568 
7569 	u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
7570 	access |= PFERR_WRITE_MASK;
7571 	return mmu->gva_to_gpa(vcpu, mmu, gva, access, exception);
7572 }
7573 EXPORT_SYMBOL_GPL(kvm_mmu_gva_to_gpa_write);
7574 
7575 /* uses this to access any guest's mapped memory without checking CPL */
kvm_mmu_gva_to_gpa_system(struct kvm_vcpu * vcpu,gva_t gva,struct x86_exception * exception)7576 gpa_t kvm_mmu_gva_to_gpa_system(struct kvm_vcpu *vcpu, gva_t gva,
7577 				struct x86_exception *exception)
7578 {
7579 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7580 
7581 	return mmu->gva_to_gpa(vcpu, mmu, gva, 0, exception);
7582 }
7583 
kvm_read_guest_virt_helper(gva_t addr,void * val,unsigned int bytes,struct kvm_vcpu * vcpu,u64 access,struct x86_exception * exception)7584 static int kvm_read_guest_virt_helper(gva_t addr, void *val, unsigned int bytes,
7585 				      struct kvm_vcpu *vcpu, u64 access,
7586 				      struct x86_exception *exception)
7587 {
7588 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7589 	void *data = val;
7590 	int r = X86EMUL_CONTINUE;
7591 
7592 	while (bytes) {
7593 		gpa_t gpa = mmu->gva_to_gpa(vcpu, mmu, addr, access, exception);
7594 		unsigned offset = addr & (PAGE_SIZE-1);
7595 		unsigned toread = min(bytes, (unsigned)PAGE_SIZE - offset);
7596 		int ret;
7597 
7598 		if (gpa == INVALID_GPA)
7599 			return X86EMUL_PROPAGATE_FAULT;
7600 		ret = kvm_vcpu_read_guest_page(vcpu, gpa >> PAGE_SHIFT, data,
7601 					       offset, toread);
7602 		if (ret < 0) {
7603 			r = X86EMUL_IO_NEEDED;
7604 			goto out;
7605 		}
7606 
7607 		bytes -= toread;
7608 		data += toread;
7609 		addr += toread;
7610 	}
7611 out:
7612 	return r;
7613 }
7614 
7615 /* used for instruction fetching */
kvm_fetch_guest_virt(struct x86_emulate_ctxt * ctxt,gva_t addr,void * val,unsigned int bytes,struct x86_exception * exception)7616 static int kvm_fetch_guest_virt(struct x86_emulate_ctxt *ctxt,
7617 				gva_t addr, void *val, unsigned int bytes,
7618 				struct x86_exception *exception)
7619 {
7620 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
7621 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7622 	u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
7623 	unsigned offset;
7624 	int ret;
7625 
7626 	/* Inline kvm_read_guest_virt_helper for speed.  */
7627 	gpa_t gpa = mmu->gva_to_gpa(vcpu, mmu, addr, access|PFERR_FETCH_MASK,
7628 				    exception);
7629 	if (unlikely(gpa == INVALID_GPA))
7630 		return X86EMUL_PROPAGATE_FAULT;
7631 
7632 	offset = addr & (PAGE_SIZE-1);
7633 	if (WARN_ON(offset + bytes > PAGE_SIZE))
7634 		bytes = (unsigned)PAGE_SIZE - offset;
7635 	ret = kvm_vcpu_read_guest_page(vcpu, gpa >> PAGE_SHIFT, val,
7636 				       offset, bytes);
7637 	if (unlikely(ret < 0))
7638 		return X86EMUL_IO_NEEDED;
7639 
7640 	return X86EMUL_CONTINUE;
7641 }
7642 
kvm_read_guest_virt(struct kvm_vcpu * vcpu,gva_t addr,void * val,unsigned int bytes,struct x86_exception * exception)7643 int kvm_read_guest_virt(struct kvm_vcpu *vcpu,
7644 			       gva_t addr, void *val, unsigned int bytes,
7645 			       struct x86_exception *exception)
7646 {
7647 	u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
7648 
7649 	/*
7650 	 * FIXME: this should call handle_emulation_failure if X86EMUL_IO_NEEDED
7651 	 * is returned, but our callers are not ready for that and they blindly
7652 	 * call kvm_inject_page_fault.  Ensure that they at least do not leak
7653 	 * uninitialized kernel stack memory into cr2 and error code.
7654 	 */
7655 	memset(exception, 0, sizeof(*exception));
7656 	return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access,
7657 					  exception);
7658 }
7659 EXPORT_SYMBOL_GPL(kvm_read_guest_virt);
7660 
emulator_read_std(struct x86_emulate_ctxt * ctxt,gva_t addr,void * val,unsigned int bytes,struct x86_exception * exception,bool system)7661 static int emulator_read_std(struct x86_emulate_ctxt *ctxt,
7662 			     gva_t addr, void *val, unsigned int bytes,
7663 			     struct x86_exception *exception, bool system)
7664 {
7665 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
7666 	u64 access = 0;
7667 
7668 	if (system)
7669 		access |= PFERR_IMPLICIT_ACCESS;
7670 	else if (static_call(kvm_x86_get_cpl)(vcpu) == 3)
7671 		access |= PFERR_USER_MASK;
7672 
7673 	return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access, exception);
7674 }
7675 
kvm_write_guest_virt_helper(gva_t addr,void * val,unsigned int bytes,struct kvm_vcpu * vcpu,u64 access,struct x86_exception * exception)7676 static int kvm_write_guest_virt_helper(gva_t addr, void *val, unsigned int bytes,
7677 				      struct kvm_vcpu *vcpu, u64 access,
7678 				      struct x86_exception *exception)
7679 {
7680 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7681 	void *data = val;
7682 	int r = X86EMUL_CONTINUE;
7683 
7684 	while (bytes) {
7685 		gpa_t gpa = mmu->gva_to_gpa(vcpu, mmu, addr, access, exception);
7686 		unsigned offset = addr & (PAGE_SIZE-1);
7687 		unsigned towrite = min(bytes, (unsigned)PAGE_SIZE - offset);
7688 		int ret;
7689 
7690 		if (gpa == INVALID_GPA)
7691 			return X86EMUL_PROPAGATE_FAULT;
7692 		ret = kvm_vcpu_write_guest(vcpu, gpa, data, towrite);
7693 		if (ret < 0) {
7694 			r = X86EMUL_IO_NEEDED;
7695 			goto out;
7696 		}
7697 
7698 		bytes -= towrite;
7699 		data += towrite;
7700 		addr += towrite;
7701 	}
7702 out:
7703 	return r;
7704 }
7705 
emulator_write_std(struct x86_emulate_ctxt * ctxt,gva_t addr,void * val,unsigned int bytes,struct x86_exception * exception,bool system)7706 static int emulator_write_std(struct x86_emulate_ctxt *ctxt, gva_t addr, void *val,
7707 			      unsigned int bytes, struct x86_exception *exception,
7708 			      bool system)
7709 {
7710 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
7711 	u64 access = PFERR_WRITE_MASK;
7712 
7713 	if (system)
7714 		access |= PFERR_IMPLICIT_ACCESS;
7715 	else if (static_call(kvm_x86_get_cpl)(vcpu) == 3)
7716 		access |= PFERR_USER_MASK;
7717 
7718 	return kvm_write_guest_virt_helper(addr, val, bytes, vcpu,
7719 					   access, exception);
7720 }
7721 
kvm_write_guest_virt_system(struct kvm_vcpu * vcpu,gva_t addr,void * val,unsigned int bytes,struct x86_exception * exception)7722 int kvm_write_guest_virt_system(struct kvm_vcpu *vcpu, gva_t addr, void *val,
7723 				unsigned int bytes, struct x86_exception *exception)
7724 {
7725 	/* kvm_write_guest_virt_system can pull in tons of pages. */
7726 	vcpu->arch.l1tf_flush_l1d = true;
7727 
7728 	return kvm_write_guest_virt_helper(addr, val, bytes, vcpu,
7729 					   PFERR_WRITE_MASK, exception);
7730 }
7731 EXPORT_SYMBOL_GPL(kvm_write_guest_virt_system);
7732 
kvm_check_emulate_insn(struct kvm_vcpu * vcpu,int emul_type,void * insn,int insn_len)7733 static int kvm_check_emulate_insn(struct kvm_vcpu *vcpu, int emul_type,
7734 				  void *insn, int insn_len)
7735 {
7736 	return static_call(kvm_x86_check_emulate_instruction)(vcpu, emul_type,
7737 							      insn, insn_len);
7738 }
7739 
handle_ud(struct kvm_vcpu * vcpu)7740 int handle_ud(struct kvm_vcpu *vcpu)
7741 {
7742 	static const char kvm_emulate_prefix[] = { __KVM_EMULATE_PREFIX };
7743 	int fep_flags = READ_ONCE(force_emulation_prefix);
7744 	int emul_type = EMULTYPE_TRAP_UD;
7745 	char sig[5]; /* ud2; .ascii "kvm" */
7746 	struct x86_exception e;
7747 	int r;
7748 
7749 	r = kvm_check_emulate_insn(vcpu, emul_type, NULL, 0);
7750 	if (r != X86EMUL_CONTINUE)
7751 		return 1;
7752 
7753 	if (fep_flags &&
7754 	    kvm_read_guest_virt(vcpu, kvm_get_linear_rip(vcpu),
7755 				sig, sizeof(sig), &e) == 0 &&
7756 	    memcmp(sig, kvm_emulate_prefix, sizeof(sig)) == 0) {
7757 		if (fep_flags & KVM_FEP_CLEAR_RFLAGS_RF)
7758 			kvm_set_rflags(vcpu, kvm_get_rflags(vcpu) & ~X86_EFLAGS_RF);
7759 		kvm_rip_write(vcpu, kvm_rip_read(vcpu) + sizeof(sig));
7760 		emul_type = EMULTYPE_TRAP_UD_FORCED;
7761 	}
7762 
7763 	return kvm_emulate_instruction(vcpu, emul_type);
7764 }
7765 EXPORT_SYMBOL_GPL(handle_ud);
7766 
vcpu_is_mmio_gpa(struct kvm_vcpu * vcpu,unsigned long gva,gpa_t gpa,bool write)7767 static int vcpu_is_mmio_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
7768 			    gpa_t gpa, bool write)
7769 {
7770 	/* For APIC access vmexit */
7771 	if ((gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
7772 		return 1;
7773 
7774 	if (vcpu_match_mmio_gpa(vcpu, gpa)) {
7775 		trace_vcpu_match_mmio(gva, gpa, write, true);
7776 		return 1;
7777 	}
7778 
7779 	return 0;
7780 }
7781 
vcpu_mmio_gva_to_gpa(struct kvm_vcpu * vcpu,unsigned long gva,gpa_t * gpa,struct x86_exception * exception,bool write)7782 static int vcpu_mmio_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
7783 				gpa_t *gpa, struct x86_exception *exception,
7784 				bool write)
7785 {
7786 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
7787 	u64 access = ((static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0)
7788 		| (write ? PFERR_WRITE_MASK : 0);
7789 
7790 	/*
7791 	 * currently PKRU is only applied to ept enabled guest so
7792 	 * there is no pkey in EPT page table for L1 guest or EPT
7793 	 * shadow page table for L2 guest.
7794 	 */
7795 	if (vcpu_match_mmio_gva(vcpu, gva) && (!is_paging(vcpu) ||
7796 	    !permission_fault(vcpu, vcpu->arch.walk_mmu,
7797 			      vcpu->arch.mmio_access, 0, access))) {
7798 		*gpa = vcpu->arch.mmio_gfn << PAGE_SHIFT |
7799 					(gva & (PAGE_SIZE - 1));
7800 		trace_vcpu_match_mmio(gva, *gpa, write, false);
7801 		return 1;
7802 	}
7803 
7804 	*gpa = mmu->gva_to_gpa(vcpu, mmu, gva, access, exception);
7805 
7806 	if (*gpa == INVALID_GPA)
7807 		return -1;
7808 
7809 	return vcpu_is_mmio_gpa(vcpu, gva, *gpa, write);
7810 }
7811 
emulator_write_phys(struct kvm_vcpu * vcpu,gpa_t gpa,const void * val,int bytes)7812 int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa,
7813 			const void *val, int bytes)
7814 {
7815 	int ret;
7816 
7817 	ret = kvm_vcpu_write_guest(vcpu, gpa, val, bytes);
7818 	if (ret < 0)
7819 		return 0;
7820 	kvm_page_track_write(vcpu, gpa, val, bytes);
7821 	return 1;
7822 }
7823 
7824 struct read_write_emulator_ops {
7825 	int (*read_write_prepare)(struct kvm_vcpu *vcpu, void *val,
7826 				  int bytes);
7827 	int (*read_write_emulate)(struct kvm_vcpu *vcpu, gpa_t gpa,
7828 				  void *val, int bytes);
7829 	int (*read_write_mmio)(struct kvm_vcpu *vcpu, gpa_t gpa,
7830 			       int bytes, void *val);
7831 	int (*read_write_exit_mmio)(struct kvm_vcpu *vcpu, gpa_t gpa,
7832 				    void *val, int bytes);
7833 	bool write;
7834 };
7835 
read_prepare(struct kvm_vcpu * vcpu,void * val,int bytes)7836 static int read_prepare(struct kvm_vcpu *vcpu, void *val, int bytes)
7837 {
7838 	if (vcpu->mmio_read_completed) {
7839 		trace_kvm_mmio(KVM_TRACE_MMIO_READ, bytes,
7840 			       vcpu->mmio_fragments[0].gpa, val);
7841 		vcpu->mmio_read_completed = 0;
7842 		return 1;
7843 	}
7844 
7845 	return 0;
7846 }
7847 
read_emulate(struct kvm_vcpu * vcpu,gpa_t gpa,void * val,int bytes)7848 static int read_emulate(struct kvm_vcpu *vcpu, gpa_t gpa,
7849 			void *val, int bytes)
7850 {
7851 	return !kvm_vcpu_read_guest(vcpu, gpa, val, bytes);
7852 }
7853 
write_emulate(struct kvm_vcpu * vcpu,gpa_t gpa,void * val,int bytes)7854 static int write_emulate(struct kvm_vcpu *vcpu, gpa_t gpa,
7855 			 void *val, int bytes)
7856 {
7857 	return emulator_write_phys(vcpu, gpa, val, bytes);
7858 }
7859 
write_mmio(struct kvm_vcpu * vcpu,gpa_t gpa,int bytes,void * val)7860 static int write_mmio(struct kvm_vcpu *vcpu, gpa_t gpa, int bytes, void *val)
7861 {
7862 	trace_kvm_mmio(KVM_TRACE_MMIO_WRITE, bytes, gpa, val);
7863 	return vcpu_mmio_write(vcpu, gpa, bytes, val);
7864 }
7865 
read_exit_mmio(struct kvm_vcpu * vcpu,gpa_t gpa,void * val,int bytes)7866 static int read_exit_mmio(struct kvm_vcpu *vcpu, gpa_t gpa,
7867 			  void *val, int bytes)
7868 {
7869 	trace_kvm_mmio(KVM_TRACE_MMIO_READ_UNSATISFIED, bytes, gpa, NULL);
7870 	return X86EMUL_IO_NEEDED;
7871 }
7872 
write_exit_mmio(struct kvm_vcpu * vcpu,gpa_t gpa,void * val,int bytes)7873 static int write_exit_mmio(struct kvm_vcpu *vcpu, gpa_t gpa,
7874 			   void *val, int bytes)
7875 {
7876 	struct kvm_mmio_fragment *frag = &vcpu->mmio_fragments[0];
7877 
7878 	memcpy(vcpu->run->mmio.data, frag->data, min(8u, frag->len));
7879 	return X86EMUL_CONTINUE;
7880 }
7881 
7882 static const struct read_write_emulator_ops read_emultor = {
7883 	.read_write_prepare = read_prepare,
7884 	.read_write_emulate = read_emulate,
7885 	.read_write_mmio = vcpu_mmio_read,
7886 	.read_write_exit_mmio = read_exit_mmio,
7887 };
7888 
7889 static const struct read_write_emulator_ops write_emultor = {
7890 	.read_write_emulate = write_emulate,
7891 	.read_write_mmio = write_mmio,
7892 	.read_write_exit_mmio = write_exit_mmio,
7893 	.write = true,
7894 };
7895 
emulator_read_write_onepage(unsigned long addr,void * val,unsigned int bytes,struct x86_exception * exception,struct kvm_vcpu * vcpu,const struct read_write_emulator_ops * ops)7896 static int emulator_read_write_onepage(unsigned long addr, void *val,
7897 				       unsigned int bytes,
7898 				       struct x86_exception *exception,
7899 				       struct kvm_vcpu *vcpu,
7900 				       const struct read_write_emulator_ops *ops)
7901 {
7902 	gpa_t gpa;
7903 	int handled, ret;
7904 	bool write = ops->write;
7905 	struct kvm_mmio_fragment *frag;
7906 	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
7907 
7908 	/*
7909 	 * If the exit was due to a NPF we may already have a GPA.
7910 	 * If the GPA is present, use it to avoid the GVA to GPA table walk.
7911 	 * Note, this cannot be used on string operations since string
7912 	 * operation using rep will only have the initial GPA from the NPF
7913 	 * occurred.
7914 	 */
7915 	if (ctxt->gpa_available && emulator_can_use_gpa(ctxt) &&
7916 	    (addr & ~PAGE_MASK) == (ctxt->gpa_val & ~PAGE_MASK)) {
7917 		gpa = ctxt->gpa_val;
7918 		ret = vcpu_is_mmio_gpa(vcpu, addr, gpa, write);
7919 	} else {
7920 		ret = vcpu_mmio_gva_to_gpa(vcpu, addr, &gpa, exception, write);
7921 		if (ret < 0)
7922 			return X86EMUL_PROPAGATE_FAULT;
7923 	}
7924 
7925 	if (!ret && ops->read_write_emulate(vcpu, gpa, val, bytes))
7926 		return X86EMUL_CONTINUE;
7927 
7928 	/*
7929 	 * Is this MMIO handled locally?
7930 	 */
7931 	handled = ops->read_write_mmio(vcpu, gpa, bytes, val);
7932 	if (handled == bytes)
7933 		return X86EMUL_CONTINUE;
7934 
7935 	gpa += handled;
7936 	bytes -= handled;
7937 	val += handled;
7938 
7939 	WARN_ON(vcpu->mmio_nr_fragments >= KVM_MAX_MMIO_FRAGMENTS);
7940 	frag = &vcpu->mmio_fragments[vcpu->mmio_nr_fragments++];
7941 	frag->gpa = gpa;
7942 	frag->data = val;
7943 	frag->len = bytes;
7944 	return X86EMUL_CONTINUE;
7945 }
7946 
emulator_read_write(struct x86_emulate_ctxt * ctxt,unsigned long addr,void * val,unsigned int bytes,struct x86_exception * exception,const struct read_write_emulator_ops * ops)7947 static int emulator_read_write(struct x86_emulate_ctxt *ctxt,
7948 			unsigned long addr,
7949 			void *val, unsigned int bytes,
7950 			struct x86_exception *exception,
7951 			const struct read_write_emulator_ops *ops)
7952 {
7953 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
7954 	gpa_t gpa;
7955 	int rc;
7956 
7957 	if (ops->read_write_prepare &&
7958 		  ops->read_write_prepare(vcpu, val, bytes))
7959 		return X86EMUL_CONTINUE;
7960 
7961 	vcpu->mmio_nr_fragments = 0;
7962 
7963 	/* Crossing a page boundary? */
7964 	if (((addr + bytes - 1) ^ addr) & PAGE_MASK) {
7965 		int now;
7966 
7967 		now = -addr & ~PAGE_MASK;
7968 		rc = emulator_read_write_onepage(addr, val, now, exception,
7969 						 vcpu, ops);
7970 
7971 		if (rc != X86EMUL_CONTINUE)
7972 			return rc;
7973 		addr += now;
7974 		if (ctxt->mode != X86EMUL_MODE_PROT64)
7975 			addr = (u32)addr;
7976 		val += now;
7977 		bytes -= now;
7978 	}
7979 
7980 	rc = emulator_read_write_onepage(addr, val, bytes, exception,
7981 					 vcpu, ops);
7982 	if (rc != X86EMUL_CONTINUE)
7983 		return rc;
7984 
7985 	if (!vcpu->mmio_nr_fragments)
7986 		return rc;
7987 
7988 	gpa = vcpu->mmio_fragments[0].gpa;
7989 
7990 	vcpu->mmio_needed = 1;
7991 	vcpu->mmio_cur_fragment = 0;
7992 
7993 	vcpu->run->mmio.len = min(8u, vcpu->mmio_fragments[0].len);
7994 	vcpu->run->mmio.is_write = vcpu->mmio_is_write = ops->write;
7995 	vcpu->run->exit_reason = KVM_EXIT_MMIO;
7996 	vcpu->run->mmio.phys_addr = gpa;
7997 
7998 	return ops->read_write_exit_mmio(vcpu, gpa, val, bytes);
7999 }
8000 
emulator_read_emulated(struct x86_emulate_ctxt * ctxt,unsigned long addr,void * val,unsigned int bytes,struct x86_exception * exception)8001 static int emulator_read_emulated(struct x86_emulate_ctxt *ctxt,
8002 				  unsigned long addr,
8003 				  void *val,
8004 				  unsigned int bytes,
8005 				  struct x86_exception *exception)
8006 {
8007 	return emulator_read_write(ctxt, addr, val, bytes,
8008 				   exception, &read_emultor);
8009 }
8010 
emulator_write_emulated(struct x86_emulate_ctxt * ctxt,unsigned long addr,const void * val,unsigned int bytes,struct x86_exception * exception)8011 static int emulator_write_emulated(struct x86_emulate_ctxt *ctxt,
8012 			    unsigned long addr,
8013 			    const void *val,
8014 			    unsigned int bytes,
8015 			    struct x86_exception *exception)
8016 {
8017 	return emulator_read_write(ctxt, addr, (void *)val, bytes,
8018 				   exception, &write_emultor);
8019 }
8020 
8021 #define emulator_try_cmpxchg_user(t, ptr, old, new) \
8022 	(__try_cmpxchg_user((t __user *)(ptr), (t *)(old), *(t *)(new), efault ## t))
8023 
emulator_cmpxchg_emulated(struct x86_emulate_ctxt * ctxt,unsigned long addr,const void * old,const void * new,unsigned int bytes,struct x86_exception * exception)8024 static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt,
8025 				     unsigned long addr,
8026 				     const void *old,
8027 				     const void *new,
8028 				     unsigned int bytes,
8029 				     struct x86_exception *exception)
8030 {
8031 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8032 	u64 page_line_mask;
8033 	unsigned long hva;
8034 	gpa_t gpa;
8035 	int r;
8036 
8037 	/* guests cmpxchg8b have to be emulated atomically */
8038 	if (bytes > 8 || (bytes & (bytes - 1)))
8039 		goto emul_write;
8040 
8041 	gpa = kvm_mmu_gva_to_gpa_write(vcpu, addr, NULL);
8042 
8043 	if (gpa == INVALID_GPA ||
8044 	    (gpa & PAGE_MASK) == APIC_DEFAULT_PHYS_BASE)
8045 		goto emul_write;
8046 
8047 	/*
8048 	 * Emulate the atomic as a straight write to avoid #AC if SLD is
8049 	 * enabled in the host and the access splits a cache line.
8050 	 */
8051 	if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT))
8052 		page_line_mask = ~(cache_line_size() - 1);
8053 	else
8054 		page_line_mask = PAGE_MASK;
8055 
8056 	if (((gpa + bytes - 1) & page_line_mask) != (gpa & page_line_mask))
8057 		goto emul_write;
8058 
8059 	hva = kvm_vcpu_gfn_to_hva(vcpu, gpa_to_gfn(gpa));
8060 	if (kvm_is_error_hva(hva))
8061 		goto emul_write;
8062 
8063 	hva += offset_in_page(gpa);
8064 
8065 	switch (bytes) {
8066 	case 1:
8067 		r = emulator_try_cmpxchg_user(u8, hva, old, new);
8068 		break;
8069 	case 2:
8070 		r = emulator_try_cmpxchg_user(u16, hva, old, new);
8071 		break;
8072 	case 4:
8073 		r = emulator_try_cmpxchg_user(u32, hva, old, new);
8074 		break;
8075 	case 8:
8076 		r = emulator_try_cmpxchg_user(u64, hva, old, new);
8077 		break;
8078 	default:
8079 		BUG();
8080 	}
8081 
8082 	if (r < 0)
8083 		return X86EMUL_UNHANDLEABLE;
8084 
8085 	/*
8086 	 * Mark the page dirty _before_ checking whether or not the CMPXCHG was
8087 	 * successful, as the old value is written back on failure.  Note, for
8088 	 * live migration, this is unnecessarily conservative as CMPXCHG writes
8089 	 * back the original value and the access is atomic, but KVM's ABI is
8090 	 * that all writes are dirty logged, regardless of the value written.
8091 	 */
8092 	kvm_vcpu_mark_page_dirty(vcpu, gpa_to_gfn(gpa));
8093 
8094 	if (r)
8095 		return X86EMUL_CMPXCHG_FAILED;
8096 
8097 	kvm_page_track_write(vcpu, gpa, new, bytes);
8098 
8099 	return X86EMUL_CONTINUE;
8100 
8101 emul_write:
8102 	pr_warn_once("emulating exchange as write\n");
8103 
8104 	return emulator_write_emulated(ctxt, addr, new, bytes, exception);
8105 }
8106 
emulator_pio_in_out(struct kvm_vcpu * vcpu,int size,unsigned short port,void * data,unsigned int count,bool in)8107 static int emulator_pio_in_out(struct kvm_vcpu *vcpu, int size,
8108 			       unsigned short port, void *data,
8109 			       unsigned int count, bool in)
8110 {
8111 	unsigned i;
8112 	int r;
8113 
8114 	WARN_ON_ONCE(vcpu->arch.pio.count);
8115 	for (i = 0; i < count; i++) {
8116 		if (in)
8117 			r = kvm_io_bus_read(vcpu, KVM_PIO_BUS, port, size, data);
8118 		else
8119 			r = kvm_io_bus_write(vcpu, KVM_PIO_BUS, port, size, data);
8120 
8121 		if (r) {
8122 			if (i == 0)
8123 				goto userspace_io;
8124 
8125 			/*
8126 			 * Userspace must have unregistered the device while PIO
8127 			 * was running.  Drop writes / read as 0.
8128 			 */
8129 			if (in)
8130 				memset(data, 0, size * (count - i));
8131 			break;
8132 		}
8133 
8134 		data += size;
8135 	}
8136 	return 1;
8137 
8138 userspace_io:
8139 	vcpu->arch.pio.port = port;
8140 	vcpu->arch.pio.in = in;
8141 	vcpu->arch.pio.count = count;
8142 	vcpu->arch.pio.size = size;
8143 
8144 	if (in)
8145 		memset(vcpu->arch.pio_data, 0, size * count);
8146 	else
8147 		memcpy(vcpu->arch.pio_data, data, size * count);
8148 
8149 	vcpu->run->exit_reason = KVM_EXIT_IO;
8150 	vcpu->run->io.direction = in ? KVM_EXIT_IO_IN : KVM_EXIT_IO_OUT;
8151 	vcpu->run->io.size = size;
8152 	vcpu->run->io.data_offset = KVM_PIO_PAGE_OFFSET * PAGE_SIZE;
8153 	vcpu->run->io.count = count;
8154 	vcpu->run->io.port = port;
8155 	return 0;
8156 }
8157 
emulator_pio_in(struct kvm_vcpu * vcpu,int size,unsigned short port,void * val,unsigned int count)8158 static int emulator_pio_in(struct kvm_vcpu *vcpu, int size,
8159       			   unsigned short port, void *val, unsigned int count)
8160 {
8161 	int r = emulator_pio_in_out(vcpu, size, port, val, count, true);
8162 	if (r)
8163 		trace_kvm_pio(KVM_PIO_IN, port, size, count, val);
8164 
8165 	return r;
8166 }
8167 
complete_emulator_pio_in(struct kvm_vcpu * vcpu,void * val)8168 static void complete_emulator_pio_in(struct kvm_vcpu *vcpu, void *val)
8169 {
8170 	int size = vcpu->arch.pio.size;
8171 	unsigned int count = vcpu->arch.pio.count;
8172 	memcpy(val, vcpu->arch.pio_data, size * count);
8173 	trace_kvm_pio(KVM_PIO_IN, vcpu->arch.pio.port, size, count, vcpu->arch.pio_data);
8174 	vcpu->arch.pio.count = 0;
8175 }
8176 
emulator_pio_in_emulated(struct x86_emulate_ctxt * ctxt,int size,unsigned short port,void * val,unsigned int count)8177 static int emulator_pio_in_emulated(struct x86_emulate_ctxt *ctxt,
8178 				    int size, unsigned short port, void *val,
8179 				    unsigned int count)
8180 {
8181 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8182 	if (vcpu->arch.pio.count) {
8183 		/*
8184 		 * Complete a previous iteration that required userspace I/O.
8185 		 * Note, @count isn't guaranteed to match pio.count as userspace
8186 		 * can modify ECX before rerunning the vCPU.  Ignore any such
8187 		 * shenanigans as KVM doesn't support modifying the rep count,
8188 		 * and the emulator ensures @count doesn't overflow the buffer.
8189 		 */
8190 		complete_emulator_pio_in(vcpu, val);
8191 		return 1;
8192 	}
8193 
8194 	return emulator_pio_in(vcpu, size, port, val, count);
8195 }
8196 
emulator_pio_out(struct kvm_vcpu * vcpu,int size,unsigned short port,const void * val,unsigned int count)8197 static int emulator_pio_out(struct kvm_vcpu *vcpu, int size,
8198 			    unsigned short port, const void *val,
8199 			    unsigned int count)
8200 {
8201 	trace_kvm_pio(KVM_PIO_OUT, port, size, count, val);
8202 	return emulator_pio_in_out(vcpu, size, port, (void *)val, count, false);
8203 }
8204 
emulator_pio_out_emulated(struct x86_emulate_ctxt * ctxt,int size,unsigned short port,const void * val,unsigned int count)8205 static int emulator_pio_out_emulated(struct x86_emulate_ctxt *ctxt,
8206 				     int size, unsigned short port,
8207 				     const void *val, unsigned int count)
8208 {
8209 	return emulator_pio_out(emul_to_vcpu(ctxt), size, port, val, count);
8210 }
8211 
get_segment_base(struct kvm_vcpu * vcpu,int seg)8212 static unsigned long get_segment_base(struct kvm_vcpu *vcpu, int seg)
8213 {
8214 	return static_call(kvm_x86_get_segment_base)(vcpu, seg);
8215 }
8216 
emulator_invlpg(struct x86_emulate_ctxt * ctxt,ulong address)8217 static void emulator_invlpg(struct x86_emulate_ctxt *ctxt, ulong address)
8218 {
8219 	kvm_mmu_invlpg(emul_to_vcpu(ctxt), address);
8220 }
8221 
kvm_emulate_wbinvd_noskip(struct kvm_vcpu * vcpu)8222 static int kvm_emulate_wbinvd_noskip(struct kvm_vcpu *vcpu)
8223 {
8224 	if (!need_emulate_wbinvd(vcpu))
8225 		return X86EMUL_CONTINUE;
8226 
8227 	if (static_call(kvm_x86_has_wbinvd_exit)()) {
8228 		int cpu = get_cpu();
8229 
8230 		cpumask_set_cpu(cpu, vcpu->arch.wbinvd_dirty_mask);
8231 		on_each_cpu_mask(vcpu->arch.wbinvd_dirty_mask,
8232 				wbinvd_ipi, NULL, 1);
8233 		put_cpu();
8234 		cpumask_clear(vcpu->arch.wbinvd_dirty_mask);
8235 	} else
8236 		wbinvd();
8237 	return X86EMUL_CONTINUE;
8238 }
8239 
kvm_emulate_wbinvd(struct kvm_vcpu * vcpu)8240 int kvm_emulate_wbinvd(struct kvm_vcpu *vcpu)
8241 {
8242 	kvm_emulate_wbinvd_noskip(vcpu);
8243 	return kvm_skip_emulated_instruction(vcpu);
8244 }
8245 EXPORT_SYMBOL_GPL(kvm_emulate_wbinvd);
8246 
8247 
8248 
emulator_wbinvd(struct x86_emulate_ctxt * ctxt)8249 static void emulator_wbinvd(struct x86_emulate_ctxt *ctxt)
8250 {
8251 	kvm_emulate_wbinvd_noskip(emul_to_vcpu(ctxt));
8252 }
8253 
emulator_get_dr(struct x86_emulate_ctxt * ctxt,int dr)8254 static unsigned long emulator_get_dr(struct x86_emulate_ctxt *ctxt, int dr)
8255 {
8256 	return kvm_get_dr(emul_to_vcpu(ctxt), dr);
8257 }
8258 
emulator_set_dr(struct x86_emulate_ctxt * ctxt,int dr,unsigned long value)8259 static int emulator_set_dr(struct x86_emulate_ctxt *ctxt, int dr,
8260 			   unsigned long value)
8261 {
8262 
8263 	return kvm_set_dr(emul_to_vcpu(ctxt), dr, value);
8264 }
8265 
mk_cr_64(u64 curr_cr,u32 new_val)8266 static u64 mk_cr_64(u64 curr_cr, u32 new_val)
8267 {
8268 	return (curr_cr & ~((1ULL << 32) - 1)) | new_val;
8269 }
8270 
emulator_get_cr(struct x86_emulate_ctxt * ctxt,int cr)8271 static unsigned long emulator_get_cr(struct x86_emulate_ctxt *ctxt, int cr)
8272 {
8273 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8274 	unsigned long value;
8275 
8276 	switch (cr) {
8277 	case 0:
8278 		value = kvm_read_cr0(vcpu);
8279 		break;
8280 	case 2:
8281 		value = vcpu->arch.cr2;
8282 		break;
8283 	case 3:
8284 		value = kvm_read_cr3(vcpu);
8285 		break;
8286 	case 4:
8287 		value = kvm_read_cr4(vcpu);
8288 		break;
8289 	case 8:
8290 		value = kvm_get_cr8(vcpu);
8291 		break;
8292 	default:
8293 		kvm_err("%s: unexpected cr %u\n", __func__, cr);
8294 		return 0;
8295 	}
8296 
8297 	return value;
8298 }
8299 
emulator_set_cr(struct x86_emulate_ctxt * ctxt,int cr,ulong val)8300 static int emulator_set_cr(struct x86_emulate_ctxt *ctxt, int cr, ulong val)
8301 {
8302 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8303 	int res = 0;
8304 
8305 	switch (cr) {
8306 	case 0:
8307 		res = kvm_set_cr0(vcpu, mk_cr_64(kvm_read_cr0(vcpu), val));
8308 		break;
8309 	case 2:
8310 		vcpu->arch.cr2 = val;
8311 		break;
8312 	case 3:
8313 		res = kvm_set_cr3(vcpu, val);
8314 		break;
8315 	case 4:
8316 		res = kvm_set_cr4(vcpu, mk_cr_64(kvm_read_cr4(vcpu), val));
8317 		break;
8318 	case 8:
8319 		res = kvm_set_cr8(vcpu, val);
8320 		break;
8321 	default:
8322 		kvm_err("%s: unexpected cr %u\n", __func__, cr);
8323 		res = -1;
8324 	}
8325 
8326 	return res;
8327 }
8328 
emulator_get_cpl(struct x86_emulate_ctxt * ctxt)8329 static int emulator_get_cpl(struct x86_emulate_ctxt *ctxt)
8330 {
8331 	return static_call(kvm_x86_get_cpl)(emul_to_vcpu(ctxt));
8332 }
8333 
emulator_get_gdt(struct x86_emulate_ctxt * ctxt,struct desc_ptr * dt)8334 static void emulator_get_gdt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt)
8335 {
8336 	static_call(kvm_x86_get_gdt)(emul_to_vcpu(ctxt), dt);
8337 }
8338 
emulator_get_idt(struct x86_emulate_ctxt * ctxt,struct desc_ptr * dt)8339 static void emulator_get_idt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt)
8340 {
8341 	static_call(kvm_x86_get_idt)(emul_to_vcpu(ctxt), dt);
8342 }
8343 
emulator_set_gdt(struct x86_emulate_ctxt * ctxt,struct desc_ptr * dt)8344 static void emulator_set_gdt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt)
8345 {
8346 	static_call(kvm_x86_set_gdt)(emul_to_vcpu(ctxt), dt);
8347 }
8348 
emulator_set_idt(struct x86_emulate_ctxt * ctxt,struct desc_ptr * dt)8349 static void emulator_set_idt(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt)
8350 {
8351 	static_call(kvm_x86_set_idt)(emul_to_vcpu(ctxt), dt);
8352 }
8353 
emulator_get_cached_segment_base(struct x86_emulate_ctxt * ctxt,int seg)8354 static unsigned long emulator_get_cached_segment_base(
8355 	struct x86_emulate_ctxt *ctxt, int seg)
8356 {
8357 	return get_segment_base(emul_to_vcpu(ctxt), seg);
8358 }
8359 
emulator_get_segment(struct x86_emulate_ctxt * ctxt,u16 * selector,struct desc_struct * desc,u32 * base3,int seg)8360 static bool emulator_get_segment(struct x86_emulate_ctxt *ctxt, u16 *selector,
8361 				 struct desc_struct *desc, u32 *base3,
8362 				 int seg)
8363 {
8364 	struct kvm_segment var;
8365 
8366 	kvm_get_segment(emul_to_vcpu(ctxt), &var, seg);
8367 	*selector = var.selector;
8368 
8369 	if (var.unusable) {
8370 		memset(desc, 0, sizeof(*desc));
8371 		if (base3)
8372 			*base3 = 0;
8373 		return false;
8374 	}
8375 
8376 	if (var.g)
8377 		var.limit >>= 12;
8378 	set_desc_limit(desc, var.limit);
8379 	set_desc_base(desc, (unsigned long)var.base);
8380 #ifdef CONFIG_X86_64
8381 	if (base3)
8382 		*base3 = var.base >> 32;
8383 #endif
8384 	desc->type = var.type;
8385 	desc->s = var.s;
8386 	desc->dpl = var.dpl;
8387 	desc->p = var.present;
8388 	desc->avl = var.avl;
8389 	desc->l = var.l;
8390 	desc->d = var.db;
8391 	desc->g = var.g;
8392 
8393 	return true;
8394 }
8395 
emulator_set_segment(struct x86_emulate_ctxt * ctxt,u16 selector,struct desc_struct * desc,u32 base3,int seg)8396 static void emulator_set_segment(struct x86_emulate_ctxt *ctxt, u16 selector,
8397 				 struct desc_struct *desc, u32 base3,
8398 				 int seg)
8399 {
8400 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8401 	struct kvm_segment var;
8402 
8403 	var.selector = selector;
8404 	var.base = get_desc_base(desc);
8405 #ifdef CONFIG_X86_64
8406 	var.base |= ((u64)base3) << 32;
8407 #endif
8408 	var.limit = get_desc_limit(desc);
8409 	if (desc->g)
8410 		var.limit = (var.limit << 12) | 0xfff;
8411 	var.type = desc->type;
8412 	var.dpl = desc->dpl;
8413 	var.db = desc->d;
8414 	var.s = desc->s;
8415 	var.l = desc->l;
8416 	var.g = desc->g;
8417 	var.avl = desc->avl;
8418 	var.present = desc->p;
8419 	var.unusable = !var.present;
8420 	var.padding = 0;
8421 
8422 	kvm_set_segment(vcpu, &var, seg);
8423 	return;
8424 }
8425 
emulator_get_msr_with_filter(struct x86_emulate_ctxt * ctxt,u32 msr_index,u64 * pdata)8426 static int emulator_get_msr_with_filter(struct x86_emulate_ctxt *ctxt,
8427 					u32 msr_index, u64 *pdata)
8428 {
8429 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8430 	int r;
8431 
8432 	r = kvm_get_msr_with_filter(vcpu, msr_index, pdata);
8433 	if (r < 0)
8434 		return X86EMUL_UNHANDLEABLE;
8435 
8436 	if (r) {
8437 		if (kvm_msr_user_space(vcpu, msr_index, KVM_EXIT_X86_RDMSR, 0,
8438 				       complete_emulated_rdmsr, r))
8439 			return X86EMUL_IO_NEEDED;
8440 
8441 		trace_kvm_msr_read_ex(msr_index);
8442 		return X86EMUL_PROPAGATE_FAULT;
8443 	}
8444 
8445 	trace_kvm_msr_read(msr_index, *pdata);
8446 	return X86EMUL_CONTINUE;
8447 }
8448 
emulator_set_msr_with_filter(struct x86_emulate_ctxt * ctxt,u32 msr_index,u64 data)8449 static int emulator_set_msr_with_filter(struct x86_emulate_ctxt *ctxt,
8450 					u32 msr_index, u64 data)
8451 {
8452 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8453 	int r;
8454 
8455 	r = kvm_set_msr_with_filter(vcpu, msr_index, data);
8456 	if (r < 0)
8457 		return X86EMUL_UNHANDLEABLE;
8458 
8459 	if (r) {
8460 		if (kvm_msr_user_space(vcpu, msr_index, KVM_EXIT_X86_WRMSR, data,
8461 				       complete_emulated_msr_access, r))
8462 			return X86EMUL_IO_NEEDED;
8463 
8464 		trace_kvm_msr_write_ex(msr_index, data);
8465 		return X86EMUL_PROPAGATE_FAULT;
8466 	}
8467 
8468 	trace_kvm_msr_write(msr_index, data);
8469 	return X86EMUL_CONTINUE;
8470 }
8471 
emulator_get_msr(struct x86_emulate_ctxt * ctxt,u32 msr_index,u64 * pdata)8472 static int emulator_get_msr(struct x86_emulate_ctxt *ctxt,
8473 			    u32 msr_index, u64 *pdata)
8474 {
8475 	return kvm_get_msr(emul_to_vcpu(ctxt), msr_index, pdata);
8476 }
8477 
emulator_check_rdpmc_early(struct x86_emulate_ctxt * ctxt,u32 pmc)8478 static int emulator_check_rdpmc_early(struct x86_emulate_ctxt *ctxt, u32 pmc)
8479 {
8480 	return kvm_pmu_check_rdpmc_early(emul_to_vcpu(ctxt), pmc);
8481 }
8482 
emulator_read_pmc(struct x86_emulate_ctxt * ctxt,u32 pmc,u64 * pdata)8483 static int emulator_read_pmc(struct x86_emulate_ctxt *ctxt,
8484 			     u32 pmc, u64 *pdata)
8485 {
8486 	return kvm_pmu_rdpmc(emul_to_vcpu(ctxt), pmc, pdata);
8487 }
8488 
emulator_halt(struct x86_emulate_ctxt * ctxt)8489 static void emulator_halt(struct x86_emulate_ctxt *ctxt)
8490 {
8491 	emul_to_vcpu(ctxt)->arch.halt_request = 1;
8492 }
8493 
emulator_intercept(struct x86_emulate_ctxt * ctxt,struct x86_instruction_info * info,enum x86_intercept_stage stage)8494 static int emulator_intercept(struct x86_emulate_ctxt *ctxt,
8495 			      struct x86_instruction_info *info,
8496 			      enum x86_intercept_stage stage)
8497 {
8498 	return static_call(kvm_x86_check_intercept)(emul_to_vcpu(ctxt), info, stage,
8499 					    &ctxt->exception);
8500 }
8501 
emulator_get_cpuid(struct x86_emulate_ctxt * ctxt,u32 * eax,u32 * ebx,u32 * ecx,u32 * edx,bool exact_only)8502 static bool emulator_get_cpuid(struct x86_emulate_ctxt *ctxt,
8503 			      u32 *eax, u32 *ebx, u32 *ecx, u32 *edx,
8504 			      bool exact_only)
8505 {
8506 	return kvm_cpuid(emul_to_vcpu(ctxt), eax, ebx, ecx, edx, exact_only);
8507 }
8508 
emulator_guest_has_movbe(struct x86_emulate_ctxt * ctxt)8509 static bool emulator_guest_has_movbe(struct x86_emulate_ctxt *ctxt)
8510 {
8511 	return guest_cpuid_has(emul_to_vcpu(ctxt), X86_FEATURE_MOVBE);
8512 }
8513 
emulator_guest_has_fxsr(struct x86_emulate_ctxt * ctxt)8514 static bool emulator_guest_has_fxsr(struct x86_emulate_ctxt *ctxt)
8515 {
8516 	return guest_cpuid_has(emul_to_vcpu(ctxt), X86_FEATURE_FXSR);
8517 }
8518 
emulator_guest_has_rdpid(struct x86_emulate_ctxt * ctxt)8519 static bool emulator_guest_has_rdpid(struct x86_emulate_ctxt *ctxt)
8520 {
8521 	return guest_cpuid_has(emul_to_vcpu(ctxt), X86_FEATURE_RDPID);
8522 }
8523 
emulator_read_gpr(struct x86_emulate_ctxt * ctxt,unsigned reg)8524 static ulong emulator_read_gpr(struct x86_emulate_ctxt *ctxt, unsigned reg)
8525 {
8526 	return kvm_register_read_raw(emul_to_vcpu(ctxt), reg);
8527 }
8528 
emulator_write_gpr(struct x86_emulate_ctxt * ctxt,unsigned reg,ulong val)8529 static void emulator_write_gpr(struct x86_emulate_ctxt *ctxt, unsigned reg, ulong val)
8530 {
8531 	kvm_register_write_raw(emul_to_vcpu(ctxt), reg, val);
8532 }
8533 
emulator_set_nmi_mask(struct x86_emulate_ctxt * ctxt,bool masked)8534 static void emulator_set_nmi_mask(struct x86_emulate_ctxt *ctxt, bool masked)
8535 {
8536 	static_call(kvm_x86_set_nmi_mask)(emul_to_vcpu(ctxt), masked);
8537 }
8538 
emulator_is_smm(struct x86_emulate_ctxt * ctxt)8539 static bool emulator_is_smm(struct x86_emulate_ctxt *ctxt)
8540 {
8541 	return is_smm(emul_to_vcpu(ctxt));
8542 }
8543 
emulator_is_guest_mode(struct x86_emulate_ctxt * ctxt)8544 static bool emulator_is_guest_mode(struct x86_emulate_ctxt *ctxt)
8545 {
8546 	return is_guest_mode(emul_to_vcpu(ctxt));
8547 }
8548 
8549 #ifndef CONFIG_KVM_SMM
emulator_leave_smm(struct x86_emulate_ctxt * ctxt)8550 static int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
8551 {
8552 	WARN_ON_ONCE(1);
8553 	return X86EMUL_UNHANDLEABLE;
8554 }
8555 #endif
8556 
emulator_triple_fault(struct x86_emulate_ctxt * ctxt)8557 static void emulator_triple_fault(struct x86_emulate_ctxt *ctxt)
8558 {
8559 	kvm_make_request(KVM_REQ_TRIPLE_FAULT, emul_to_vcpu(ctxt));
8560 }
8561 
emulator_set_xcr(struct x86_emulate_ctxt * ctxt,u32 index,u64 xcr)8562 static int emulator_set_xcr(struct x86_emulate_ctxt *ctxt, u32 index, u64 xcr)
8563 {
8564 	return __kvm_set_xcr(emul_to_vcpu(ctxt), index, xcr);
8565 }
8566 
emulator_vm_bugged(struct x86_emulate_ctxt * ctxt)8567 static void emulator_vm_bugged(struct x86_emulate_ctxt *ctxt)
8568 {
8569 	struct kvm *kvm = emul_to_vcpu(ctxt)->kvm;
8570 
8571 	if (!kvm->vm_bugged)
8572 		kvm_vm_bugged(kvm);
8573 }
8574 
emulator_get_untagged_addr(struct x86_emulate_ctxt * ctxt,gva_t addr,unsigned int flags)8575 static gva_t emulator_get_untagged_addr(struct x86_emulate_ctxt *ctxt,
8576 					gva_t addr, unsigned int flags)
8577 {
8578 	if (!kvm_x86_ops.get_untagged_addr)
8579 		return addr;
8580 
8581 	return static_call(kvm_x86_get_untagged_addr)(emul_to_vcpu(ctxt), addr, flags);
8582 }
8583 
8584 static const struct x86_emulate_ops emulate_ops = {
8585 	.vm_bugged           = emulator_vm_bugged,
8586 	.read_gpr            = emulator_read_gpr,
8587 	.write_gpr           = emulator_write_gpr,
8588 	.read_std            = emulator_read_std,
8589 	.write_std           = emulator_write_std,
8590 	.fetch               = kvm_fetch_guest_virt,
8591 	.read_emulated       = emulator_read_emulated,
8592 	.write_emulated      = emulator_write_emulated,
8593 	.cmpxchg_emulated    = emulator_cmpxchg_emulated,
8594 	.invlpg              = emulator_invlpg,
8595 	.pio_in_emulated     = emulator_pio_in_emulated,
8596 	.pio_out_emulated    = emulator_pio_out_emulated,
8597 	.get_segment         = emulator_get_segment,
8598 	.set_segment         = emulator_set_segment,
8599 	.get_cached_segment_base = emulator_get_cached_segment_base,
8600 	.get_gdt             = emulator_get_gdt,
8601 	.get_idt	     = emulator_get_idt,
8602 	.set_gdt             = emulator_set_gdt,
8603 	.set_idt	     = emulator_set_idt,
8604 	.get_cr              = emulator_get_cr,
8605 	.set_cr              = emulator_set_cr,
8606 	.cpl                 = emulator_get_cpl,
8607 	.get_dr              = emulator_get_dr,
8608 	.set_dr              = emulator_set_dr,
8609 	.set_msr_with_filter = emulator_set_msr_with_filter,
8610 	.get_msr_with_filter = emulator_get_msr_with_filter,
8611 	.get_msr             = emulator_get_msr,
8612 	.check_rdpmc_early   = emulator_check_rdpmc_early,
8613 	.read_pmc            = emulator_read_pmc,
8614 	.halt                = emulator_halt,
8615 	.wbinvd              = emulator_wbinvd,
8616 	.fix_hypercall       = emulator_fix_hypercall,
8617 	.intercept           = emulator_intercept,
8618 	.get_cpuid           = emulator_get_cpuid,
8619 	.guest_has_movbe     = emulator_guest_has_movbe,
8620 	.guest_has_fxsr      = emulator_guest_has_fxsr,
8621 	.guest_has_rdpid     = emulator_guest_has_rdpid,
8622 	.set_nmi_mask        = emulator_set_nmi_mask,
8623 	.is_smm              = emulator_is_smm,
8624 	.is_guest_mode       = emulator_is_guest_mode,
8625 	.leave_smm           = emulator_leave_smm,
8626 	.triple_fault        = emulator_triple_fault,
8627 	.set_xcr             = emulator_set_xcr,
8628 	.get_untagged_addr   = emulator_get_untagged_addr,
8629 };
8630 
toggle_interruptibility(struct kvm_vcpu * vcpu,u32 mask)8631 static void toggle_interruptibility(struct kvm_vcpu *vcpu, u32 mask)
8632 {
8633 	u32 int_shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu);
8634 	/*
8635 	 * an sti; sti; sequence only disable interrupts for the first
8636 	 * instruction. So, if the last instruction, be it emulated or
8637 	 * not, left the system with the INT_STI flag enabled, it
8638 	 * means that the last instruction is an sti. We should not
8639 	 * leave the flag on in this case. The same goes for mov ss
8640 	 */
8641 	if (int_shadow & mask)
8642 		mask = 0;
8643 	if (unlikely(int_shadow || mask)) {
8644 		static_call(kvm_x86_set_interrupt_shadow)(vcpu, mask);
8645 		if (!mask)
8646 			kvm_make_request(KVM_REQ_EVENT, vcpu);
8647 	}
8648 }
8649 
inject_emulated_exception(struct kvm_vcpu * vcpu)8650 static void inject_emulated_exception(struct kvm_vcpu *vcpu)
8651 {
8652 	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
8653 
8654 	if (ctxt->exception.vector == PF_VECTOR)
8655 		kvm_inject_emulated_page_fault(vcpu, &ctxt->exception);
8656 	else if (ctxt->exception.error_code_valid)
8657 		kvm_queue_exception_e(vcpu, ctxt->exception.vector,
8658 				      ctxt->exception.error_code);
8659 	else
8660 		kvm_queue_exception(vcpu, ctxt->exception.vector);
8661 }
8662 
alloc_emulate_ctxt(struct kvm_vcpu * vcpu)8663 static struct x86_emulate_ctxt *alloc_emulate_ctxt(struct kvm_vcpu *vcpu)
8664 {
8665 	struct x86_emulate_ctxt *ctxt;
8666 
8667 	ctxt = kmem_cache_zalloc(x86_emulator_cache, GFP_KERNEL_ACCOUNT);
8668 	if (!ctxt) {
8669 		pr_err("failed to allocate vcpu's emulator\n");
8670 		return NULL;
8671 	}
8672 
8673 	ctxt->vcpu = vcpu;
8674 	ctxt->ops = &emulate_ops;
8675 	vcpu->arch.emulate_ctxt = ctxt;
8676 
8677 	return ctxt;
8678 }
8679 
init_emulate_ctxt(struct kvm_vcpu * vcpu)8680 static void init_emulate_ctxt(struct kvm_vcpu *vcpu)
8681 {
8682 	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
8683 	int cs_db, cs_l;
8684 
8685 	static_call(kvm_x86_get_cs_db_l_bits)(vcpu, &cs_db, &cs_l);
8686 
8687 	ctxt->gpa_available = false;
8688 	ctxt->eflags = kvm_get_rflags(vcpu);
8689 	ctxt->tf = (ctxt->eflags & X86_EFLAGS_TF) != 0;
8690 
8691 	ctxt->eip = kvm_rip_read(vcpu);
8692 	ctxt->mode = (!is_protmode(vcpu))		? X86EMUL_MODE_REAL :
8693 		     (ctxt->eflags & X86_EFLAGS_VM)	? X86EMUL_MODE_VM86 :
8694 		     (cs_l && is_long_mode(vcpu))	? X86EMUL_MODE_PROT64 :
8695 		     cs_db				? X86EMUL_MODE_PROT32 :
8696 							  X86EMUL_MODE_PROT16;
8697 	ctxt->interruptibility = 0;
8698 	ctxt->have_exception = false;
8699 	ctxt->exception.vector = -1;
8700 	ctxt->perm_ok = false;
8701 
8702 	init_decode_cache(ctxt);
8703 	vcpu->arch.emulate_regs_need_sync_from_vcpu = false;
8704 }
8705 
kvm_inject_realmode_interrupt(struct kvm_vcpu * vcpu,int irq,int inc_eip)8706 void kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip)
8707 {
8708 	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
8709 	int ret;
8710 
8711 	init_emulate_ctxt(vcpu);
8712 
8713 	ctxt->op_bytes = 2;
8714 	ctxt->ad_bytes = 2;
8715 	ctxt->_eip = ctxt->eip + inc_eip;
8716 	ret = emulate_int_real(ctxt, irq);
8717 
8718 	if (ret != X86EMUL_CONTINUE) {
8719 		kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
8720 	} else {
8721 		ctxt->eip = ctxt->_eip;
8722 		kvm_rip_write(vcpu, ctxt->eip);
8723 		kvm_set_rflags(vcpu, ctxt->eflags);
8724 	}
8725 }
8726 EXPORT_SYMBOL_GPL(kvm_inject_realmode_interrupt);
8727 
prepare_emulation_failure_exit(struct kvm_vcpu * vcpu,u64 * data,u8 ndata,u8 * insn_bytes,u8 insn_size)8728 static void prepare_emulation_failure_exit(struct kvm_vcpu *vcpu, u64 *data,
8729 					   u8 ndata, u8 *insn_bytes, u8 insn_size)
8730 {
8731 	struct kvm_run *run = vcpu->run;
8732 	u64 info[5];
8733 	u8 info_start;
8734 
8735 	/*
8736 	 * Zero the whole array used to retrieve the exit info, as casting to
8737 	 * u32 for select entries will leave some chunks uninitialized.
8738 	 */
8739 	memset(&info, 0, sizeof(info));
8740 
8741 	static_call(kvm_x86_get_exit_info)(vcpu, (u32 *)&info[0], &info[1],
8742 					   &info[2], (u32 *)&info[3],
8743 					   (u32 *)&info[4]);
8744 
8745 	run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
8746 	run->emulation_failure.suberror = KVM_INTERNAL_ERROR_EMULATION;
8747 
8748 	/*
8749 	 * There's currently space for 13 entries, but 5 are used for the exit
8750 	 * reason and info.  Restrict to 4 to reduce the maintenance burden
8751 	 * when expanding kvm_run.emulation_failure in the future.
8752 	 */
8753 	if (WARN_ON_ONCE(ndata > 4))
8754 		ndata = 4;
8755 
8756 	/* Always include the flags as a 'data' entry. */
8757 	info_start = 1;
8758 	run->emulation_failure.flags = 0;
8759 
8760 	if (insn_size) {
8761 		BUILD_BUG_ON((sizeof(run->emulation_failure.insn_size) +
8762 			      sizeof(run->emulation_failure.insn_bytes) != 16));
8763 		info_start += 2;
8764 		run->emulation_failure.flags |=
8765 			KVM_INTERNAL_ERROR_EMULATION_FLAG_INSTRUCTION_BYTES;
8766 		run->emulation_failure.insn_size = insn_size;
8767 		memset(run->emulation_failure.insn_bytes, 0x90,
8768 		       sizeof(run->emulation_failure.insn_bytes));
8769 		memcpy(run->emulation_failure.insn_bytes, insn_bytes, insn_size);
8770 	}
8771 
8772 	memcpy(&run->internal.data[info_start], info, sizeof(info));
8773 	memcpy(&run->internal.data[info_start + ARRAY_SIZE(info)], data,
8774 	       ndata * sizeof(data[0]));
8775 
8776 	run->emulation_failure.ndata = info_start + ARRAY_SIZE(info) + ndata;
8777 }
8778 
prepare_emulation_ctxt_failure_exit(struct kvm_vcpu * vcpu)8779 static void prepare_emulation_ctxt_failure_exit(struct kvm_vcpu *vcpu)
8780 {
8781 	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
8782 
8783 	prepare_emulation_failure_exit(vcpu, NULL, 0, ctxt->fetch.data,
8784 				       ctxt->fetch.end - ctxt->fetch.data);
8785 }
8786 
__kvm_prepare_emulation_failure_exit(struct kvm_vcpu * vcpu,u64 * data,u8 ndata)8787 void __kvm_prepare_emulation_failure_exit(struct kvm_vcpu *vcpu, u64 *data,
8788 					  u8 ndata)
8789 {
8790 	prepare_emulation_failure_exit(vcpu, data, ndata, NULL, 0);
8791 }
8792 EXPORT_SYMBOL_GPL(__kvm_prepare_emulation_failure_exit);
8793 
kvm_prepare_emulation_failure_exit(struct kvm_vcpu * vcpu)8794 void kvm_prepare_emulation_failure_exit(struct kvm_vcpu *vcpu)
8795 {
8796 	__kvm_prepare_emulation_failure_exit(vcpu, NULL, 0);
8797 }
8798 EXPORT_SYMBOL_GPL(kvm_prepare_emulation_failure_exit);
8799 
handle_emulation_failure(struct kvm_vcpu * vcpu,int emulation_type)8800 static int handle_emulation_failure(struct kvm_vcpu *vcpu, int emulation_type)
8801 {
8802 	struct kvm *kvm = vcpu->kvm;
8803 
8804 	++vcpu->stat.insn_emulation_fail;
8805 	trace_kvm_emulate_insn_failed(vcpu);
8806 
8807 	if (emulation_type & EMULTYPE_VMWARE_GP) {
8808 		kvm_queue_exception_e(vcpu, GP_VECTOR, 0);
8809 		return 1;
8810 	}
8811 
8812 	if (kvm->arch.exit_on_emulation_error ||
8813 	    (emulation_type & EMULTYPE_SKIP)) {
8814 		prepare_emulation_ctxt_failure_exit(vcpu);
8815 		return 0;
8816 	}
8817 
8818 	kvm_queue_exception(vcpu, UD_VECTOR);
8819 
8820 	if (!is_guest_mode(vcpu) && static_call(kvm_x86_get_cpl)(vcpu) == 0) {
8821 		prepare_emulation_ctxt_failure_exit(vcpu);
8822 		return 0;
8823 	}
8824 
8825 	return 1;
8826 }
8827 
reexecute_instruction(struct kvm_vcpu * vcpu,gpa_t cr2_or_gpa,int emulation_type)8828 static bool reexecute_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
8829 				  int emulation_type)
8830 {
8831 	gpa_t gpa = cr2_or_gpa;
8832 	kvm_pfn_t pfn;
8833 
8834 	if (!(emulation_type & EMULTYPE_ALLOW_RETRY_PF))
8835 		return false;
8836 
8837 	if (WARN_ON_ONCE(is_guest_mode(vcpu)) ||
8838 	    WARN_ON_ONCE(!(emulation_type & EMULTYPE_PF)))
8839 		return false;
8840 
8841 	if (!vcpu->arch.mmu->root_role.direct) {
8842 		/*
8843 		 * Write permission should be allowed since only
8844 		 * write access need to be emulated.
8845 		 */
8846 		gpa = kvm_mmu_gva_to_gpa_write(vcpu, cr2_or_gpa, NULL);
8847 
8848 		/*
8849 		 * If the mapping is invalid in guest, let cpu retry
8850 		 * it to generate fault.
8851 		 */
8852 		if (gpa == INVALID_GPA)
8853 			return true;
8854 	}
8855 
8856 	/*
8857 	 * Do not retry the unhandleable instruction if it faults on the
8858 	 * readonly host memory, otherwise it will goto a infinite loop:
8859 	 * retry instruction -> write #PF -> emulation fail -> retry
8860 	 * instruction -> ...
8861 	 */
8862 	pfn = gfn_to_pfn(vcpu->kvm, gpa_to_gfn(gpa));
8863 
8864 	/*
8865 	 * If the instruction failed on the error pfn, it can not be fixed,
8866 	 * report the error to userspace.
8867 	 */
8868 	if (is_error_noslot_pfn(pfn))
8869 		return false;
8870 
8871 	kvm_release_pfn_clean(pfn);
8872 
8873 	/*
8874 	 * If emulation may have been triggered by a write to a shadowed page
8875 	 * table, unprotect the gfn (zap any relevant SPTEs) and re-enter the
8876 	 * guest to let the CPU re-execute the instruction in the hope that the
8877 	 * CPU can cleanly execute the instruction that KVM failed to emulate.
8878 	 */
8879 	if (vcpu->kvm->arch.indirect_shadow_pages)
8880 		kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa));
8881 
8882 	/*
8883 	 * If the failed instruction faulted on an access to page tables that
8884 	 * are used to translate any part of the instruction, KVM can't resolve
8885 	 * the issue by unprotecting the gfn, as zapping the shadow page will
8886 	 * result in the instruction taking a !PRESENT page fault and thus put
8887 	 * the vCPU into an infinite loop of page faults.  E.g. KVM will create
8888 	 * a SPTE and write-protect the gfn to resolve the !PRESENT fault, and
8889 	 * then zap the SPTE to unprotect the gfn, and then do it all over
8890 	 * again.  Report the error to userspace.
8891 	 */
8892 	return !(emulation_type & EMULTYPE_WRITE_PF_TO_SP);
8893 }
8894 
retry_instruction(struct x86_emulate_ctxt * ctxt,gpa_t cr2_or_gpa,int emulation_type)8895 static bool retry_instruction(struct x86_emulate_ctxt *ctxt,
8896 			      gpa_t cr2_or_gpa,  int emulation_type)
8897 {
8898 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
8899 	unsigned long last_retry_eip, last_retry_addr, gpa = cr2_or_gpa;
8900 
8901 	last_retry_eip = vcpu->arch.last_retry_eip;
8902 	last_retry_addr = vcpu->arch.last_retry_addr;
8903 
8904 	/*
8905 	 * If the emulation is caused by #PF and it is non-page_table
8906 	 * writing instruction, it means the VM-EXIT is caused by shadow
8907 	 * page protected, we can zap the shadow page and retry this
8908 	 * instruction directly.
8909 	 *
8910 	 * Note: if the guest uses a non-page-table modifying instruction
8911 	 * on the PDE that points to the instruction, then we will unmap
8912 	 * the instruction and go to an infinite loop. So, we cache the
8913 	 * last retried eip and the last fault address, if we meet the eip
8914 	 * and the address again, we can break out of the potential infinite
8915 	 * loop.
8916 	 */
8917 	vcpu->arch.last_retry_eip = vcpu->arch.last_retry_addr = 0;
8918 
8919 	if (!(emulation_type & EMULTYPE_ALLOW_RETRY_PF))
8920 		return false;
8921 
8922 	if (WARN_ON_ONCE(is_guest_mode(vcpu)) ||
8923 	    WARN_ON_ONCE(!(emulation_type & EMULTYPE_PF)))
8924 		return false;
8925 
8926 	if (x86_page_table_writing_insn(ctxt))
8927 		return false;
8928 
8929 	if (ctxt->eip == last_retry_eip && last_retry_addr == cr2_or_gpa)
8930 		return false;
8931 
8932 	vcpu->arch.last_retry_eip = ctxt->eip;
8933 	vcpu->arch.last_retry_addr = cr2_or_gpa;
8934 
8935 	if (!vcpu->arch.mmu->root_role.direct)
8936 		gpa = kvm_mmu_gva_to_gpa_write(vcpu, cr2_or_gpa, NULL);
8937 
8938 	kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa));
8939 
8940 	return true;
8941 }
8942 
8943 static int complete_emulated_mmio(struct kvm_vcpu *vcpu);
8944 static int complete_emulated_pio(struct kvm_vcpu *vcpu);
8945 
kvm_vcpu_check_hw_bp(unsigned long addr,u32 type,u32 dr7,unsigned long * db)8946 static int kvm_vcpu_check_hw_bp(unsigned long addr, u32 type, u32 dr7,
8947 				unsigned long *db)
8948 {
8949 	u32 dr6 = 0;
8950 	int i;
8951 	u32 enable, rwlen;
8952 
8953 	enable = dr7;
8954 	rwlen = dr7 >> 16;
8955 	for (i = 0; i < 4; i++, enable >>= 2, rwlen >>= 4)
8956 		if ((enable & 3) && (rwlen & 15) == type && db[i] == addr)
8957 			dr6 |= (1 << i);
8958 	return dr6;
8959 }
8960 
kvm_vcpu_do_singlestep(struct kvm_vcpu * vcpu)8961 static int kvm_vcpu_do_singlestep(struct kvm_vcpu *vcpu)
8962 {
8963 	struct kvm_run *kvm_run = vcpu->run;
8964 
8965 	if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
8966 		kvm_run->debug.arch.dr6 = DR6_BS | DR6_ACTIVE_LOW;
8967 		kvm_run->debug.arch.pc = kvm_get_linear_rip(vcpu);
8968 		kvm_run->debug.arch.exception = DB_VECTOR;
8969 		kvm_run->exit_reason = KVM_EXIT_DEBUG;
8970 		return 0;
8971 	}
8972 	kvm_queue_exception_p(vcpu, DB_VECTOR, DR6_BS);
8973 	return 1;
8974 }
8975 
kvm_skip_emulated_instruction(struct kvm_vcpu * vcpu)8976 int kvm_skip_emulated_instruction(struct kvm_vcpu *vcpu)
8977 {
8978 	unsigned long rflags = static_call(kvm_x86_get_rflags)(vcpu);
8979 	int r;
8980 
8981 	r = static_call(kvm_x86_skip_emulated_instruction)(vcpu);
8982 	if (unlikely(!r))
8983 		return 0;
8984 
8985 	kvm_pmu_trigger_event(vcpu, kvm_pmu_eventsel.INSTRUCTIONS_RETIRED);
8986 
8987 	/*
8988 	 * rflags is the old, "raw" value of the flags.  The new value has
8989 	 * not been saved yet.
8990 	 *
8991 	 * This is correct even for TF set by the guest, because "the
8992 	 * processor will not generate this exception after the instruction
8993 	 * that sets the TF flag".
8994 	 */
8995 	if (unlikely(rflags & X86_EFLAGS_TF))
8996 		r = kvm_vcpu_do_singlestep(vcpu);
8997 	return r;
8998 }
8999 EXPORT_SYMBOL_GPL(kvm_skip_emulated_instruction);
9000 
kvm_is_code_breakpoint_inhibited(struct kvm_vcpu * vcpu)9001 static bool kvm_is_code_breakpoint_inhibited(struct kvm_vcpu *vcpu)
9002 {
9003 	u32 shadow;
9004 
9005 	if (kvm_get_rflags(vcpu) & X86_EFLAGS_RF)
9006 		return true;
9007 
9008 	/*
9009 	 * Intel CPUs inhibit code #DBs when MOV/POP SS blocking is active,
9010 	 * but AMD CPUs do not.  MOV/POP SS blocking is rare, check that first
9011 	 * to avoid the relatively expensive CPUID lookup.
9012 	 */
9013 	shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu);
9014 	return (shadow & KVM_X86_SHADOW_INT_MOV_SS) &&
9015 	       guest_cpuid_is_intel(vcpu);
9016 }
9017 
kvm_vcpu_check_code_breakpoint(struct kvm_vcpu * vcpu,int emulation_type,int * r)9018 static bool kvm_vcpu_check_code_breakpoint(struct kvm_vcpu *vcpu,
9019 					   int emulation_type, int *r)
9020 {
9021 	WARN_ON_ONCE(emulation_type & EMULTYPE_NO_DECODE);
9022 
9023 	/*
9024 	 * Do not check for code breakpoints if hardware has already done the
9025 	 * checks, as inferred from the emulation type.  On NO_DECODE and SKIP,
9026 	 * the instruction has passed all exception checks, and all intercepted
9027 	 * exceptions that trigger emulation have lower priority than code
9028 	 * breakpoints, i.e. the fact that the intercepted exception occurred
9029 	 * means any code breakpoints have already been serviced.
9030 	 *
9031 	 * Note, KVM needs to check for code #DBs on EMULTYPE_TRAP_UD_FORCED as
9032 	 * hardware has checked the RIP of the magic prefix, but not the RIP of
9033 	 * the instruction being emulated.  The intent of forced emulation is
9034 	 * to behave as if KVM intercepted the instruction without an exception
9035 	 * and without a prefix.
9036 	 */
9037 	if (emulation_type & (EMULTYPE_NO_DECODE | EMULTYPE_SKIP |
9038 			      EMULTYPE_TRAP_UD | EMULTYPE_VMWARE_GP | EMULTYPE_PF))
9039 		return false;
9040 
9041 	if (unlikely(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) &&
9042 	    (vcpu->arch.guest_debug_dr7 & DR7_BP_EN_MASK)) {
9043 		struct kvm_run *kvm_run = vcpu->run;
9044 		unsigned long eip = kvm_get_linear_rip(vcpu);
9045 		u32 dr6 = kvm_vcpu_check_hw_bp(eip, 0,
9046 					   vcpu->arch.guest_debug_dr7,
9047 					   vcpu->arch.eff_db);
9048 
9049 		if (dr6 != 0) {
9050 			kvm_run->debug.arch.dr6 = dr6 | DR6_ACTIVE_LOW;
9051 			kvm_run->debug.arch.pc = eip;
9052 			kvm_run->debug.arch.exception = DB_VECTOR;
9053 			kvm_run->exit_reason = KVM_EXIT_DEBUG;
9054 			*r = 0;
9055 			return true;
9056 		}
9057 	}
9058 
9059 	if (unlikely(vcpu->arch.dr7 & DR7_BP_EN_MASK) &&
9060 	    !kvm_is_code_breakpoint_inhibited(vcpu)) {
9061 		unsigned long eip = kvm_get_linear_rip(vcpu);
9062 		u32 dr6 = kvm_vcpu_check_hw_bp(eip, 0,
9063 					   vcpu->arch.dr7,
9064 					   vcpu->arch.db);
9065 
9066 		if (dr6 != 0) {
9067 			kvm_queue_exception_p(vcpu, DB_VECTOR, dr6);
9068 			*r = 1;
9069 			return true;
9070 		}
9071 	}
9072 
9073 	return false;
9074 }
9075 
is_vmware_backdoor_opcode(struct x86_emulate_ctxt * ctxt)9076 static bool is_vmware_backdoor_opcode(struct x86_emulate_ctxt *ctxt)
9077 {
9078 	switch (ctxt->opcode_len) {
9079 	case 1:
9080 		switch (ctxt->b) {
9081 		case 0xe4:	/* IN */
9082 		case 0xe5:
9083 		case 0xec:
9084 		case 0xed:
9085 		case 0xe6:	/* OUT */
9086 		case 0xe7:
9087 		case 0xee:
9088 		case 0xef:
9089 		case 0x6c:	/* INS */
9090 		case 0x6d:
9091 		case 0x6e:	/* OUTS */
9092 		case 0x6f:
9093 			return true;
9094 		}
9095 		break;
9096 	case 2:
9097 		switch (ctxt->b) {
9098 		case 0x33:	/* RDPMC */
9099 			return true;
9100 		}
9101 		break;
9102 	}
9103 
9104 	return false;
9105 }
9106 
9107 /*
9108  * Decode an instruction for emulation.  The caller is responsible for handling
9109  * code breakpoints.  Note, manually detecting code breakpoints is unnecessary
9110  * (and wrong) when emulating on an intercepted fault-like exception[*], as
9111  * code breakpoints have higher priority and thus have already been done by
9112  * hardware.
9113  *
9114  * [*] Except #MC, which is higher priority, but KVM should never emulate in
9115  *     response to a machine check.
9116  */
x86_decode_emulated_instruction(struct kvm_vcpu * vcpu,int emulation_type,void * insn,int insn_len)9117 int x86_decode_emulated_instruction(struct kvm_vcpu *vcpu, int emulation_type,
9118 				    void *insn, int insn_len)
9119 {
9120 	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
9121 	int r;
9122 
9123 	init_emulate_ctxt(vcpu);
9124 
9125 	r = x86_decode_insn(ctxt, insn, insn_len, emulation_type);
9126 
9127 	trace_kvm_emulate_insn_start(vcpu);
9128 	++vcpu->stat.insn_emulation;
9129 
9130 	return r;
9131 }
9132 EXPORT_SYMBOL_GPL(x86_decode_emulated_instruction);
9133 
x86_emulate_instruction(struct kvm_vcpu * vcpu,gpa_t cr2_or_gpa,int emulation_type,void * insn,int insn_len)9134 int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
9135 			    int emulation_type, void *insn, int insn_len)
9136 {
9137 	int r;
9138 	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
9139 	bool writeback = true;
9140 
9141 	r = kvm_check_emulate_insn(vcpu, emulation_type, insn, insn_len);
9142 	if (r != X86EMUL_CONTINUE) {
9143 		if (r == X86EMUL_RETRY_INSTR || r == X86EMUL_PROPAGATE_FAULT)
9144 			return 1;
9145 
9146 		WARN_ON_ONCE(r != X86EMUL_UNHANDLEABLE);
9147 		return handle_emulation_failure(vcpu, emulation_type);
9148 	}
9149 
9150 	vcpu->arch.l1tf_flush_l1d = true;
9151 
9152 	if (!(emulation_type & EMULTYPE_NO_DECODE)) {
9153 		kvm_clear_exception_queue(vcpu);
9154 
9155 		/*
9156 		 * Return immediately if RIP hits a code breakpoint, such #DBs
9157 		 * are fault-like and are higher priority than any faults on
9158 		 * the code fetch itself.
9159 		 */
9160 		if (kvm_vcpu_check_code_breakpoint(vcpu, emulation_type, &r))
9161 			return r;
9162 
9163 		r = x86_decode_emulated_instruction(vcpu, emulation_type,
9164 						    insn, insn_len);
9165 		if (r != EMULATION_OK)  {
9166 			if ((emulation_type & EMULTYPE_TRAP_UD) ||
9167 			    (emulation_type & EMULTYPE_TRAP_UD_FORCED)) {
9168 				kvm_queue_exception(vcpu, UD_VECTOR);
9169 				return 1;
9170 			}
9171 			if (reexecute_instruction(vcpu, cr2_or_gpa,
9172 						  emulation_type))
9173 				return 1;
9174 
9175 			if (ctxt->have_exception &&
9176 			    !(emulation_type & EMULTYPE_SKIP)) {
9177 				/*
9178 				 * #UD should result in just EMULATION_FAILED, and trap-like
9179 				 * exception should not be encountered during decode.
9180 				 */
9181 				WARN_ON_ONCE(ctxt->exception.vector == UD_VECTOR ||
9182 					     exception_type(ctxt->exception.vector) == EXCPT_TRAP);
9183 				inject_emulated_exception(vcpu);
9184 				return 1;
9185 			}
9186 			return handle_emulation_failure(vcpu, emulation_type);
9187 		}
9188 	}
9189 
9190 	if ((emulation_type & EMULTYPE_VMWARE_GP) &&
9191 	    !is_vmware_backdoor_opcode(ctxt)) {
9192 		kvm_queue_exception_e(vcpu, GP_VECTOR, 0);
9193 		return 1;
9194 	}
9195 
9196 	/*
9197 	 * EMULTYPE_SKIP without EMULTYPE_COMPLETE_USER_EXIT is intended for
9198 	 * use *only* by vendor callbacks for kvm_skip_emulated_instruction().
9199 	 * The caller is responsible for updating interruptibility state and
9200 	 * injecting single-step #DBs.
9201 	 */
9202 	if (emulation_type & EMULTYPE_SKIP) {
9203 		if (ctxt->mode != X86EMUL_MODE_PROT64)
9204 			ctxt->eip = (u32)ctxt->_eip;
9205 		else
9206 			ctxt->eip = ctxt->_eip;
9207 
9208 		if (emulation_type & EMULTYPE_COMPLETE_USER_EXIT) {
9209 			r = 1;
9210 			goto writeback;
9211 		}
9212 
9213 		kvm_rip_write(vcpu, ctxt->eip);
9214 		if (ctxt->eflags & X86_EFLAGS_RF)
9215 			kvm_set_rflags(vcpu, ctxt->eflags & ~X86_EFLAGS_RF);
9216 		return 1;
9217 	}
9218 
9219 	if (retry_instruction(ctxt, cr2_or_gpa, emulation_type))
9220 		return 1;
9221 
9222 	/* this is needed for vmware backdoor interface to work since it
9223 	   changes registers values  during IO operation */
9224 	if (vcpu->arch.emulate_regs_need_sync_from_vcpu) {
9225 		vcpu->arch.emulate_regs_need_sync_from_vcpu = false;
9226 		emulator_invalidate_register_cache(ctxt);
9227 	}
9228 
9229 restart:
9230 	if (emulation_type & EMULTYPE_PF) {
9231 		/* Save the faulting GPA (cr2) in the address field */
9232 		ctxt->exception.address = cr2_or_gpa;
9233 
9234 		/* With shadow page tables, cr2 contains a GVA or nGPA. */
9235 		if (vcpu->arch.mmu->root_role.direct) {
9236 			ctxt->gpa_available = true;
9237 			ctxt->gpa_val = cr2_or_gpa;
9238 		}
9239 	} else {
9240 		/* Sanitize the address out of an abundance of paranoia. */
9241 		ctxt->exception.address = 0;
9242 	}
9243 
9244 	r = x86_emulate_insn(ctxt);
9245 
9246 	if (r == EMULATION_INTERCEPTED)
9247 		return 1;
9248 
9249 	if (r == EMULATION_FAILED) {
9250 		if (reexecute_instruction(vcpu, cr2_or_gpa, emulation_type))
9251 			return 1;
9252 
9253 		return handle_emulation_failure(vcpu, emulation_type);
9254 	}
9255 
9256 	if (ctxt->have_exception) {
9257 		WARN_ON_ONCE(vcpu->mmio_needed && !vcpu->mmio_is_write);
9258 		vcpu->mmio_needed = false;
9259 		r = 1;
9260 		inject_emulated_exception(vcpu);
9261 	} else if (vcpu->arch.pio.count) {
9262 		if (!vcpu->arch.pio.in) {
9263 			/* FIXME: return into emulator if single-stepping.  */
9264 			vcpu->arch.pio.count = 0;
9265 		} else {
9266 			writeback = false;
9267 			vcpu->arch.complete_userspace_io = complete_emulated_pio;
9268 		}
9269 		r = 0;
9270 	} else if (vcpu->mmio_needed) {
9271 		++vcpu->stat.mmio_exits;
9272 
9273 		if (!vcpu->mmio_is_write)
9274 			writeback = false;
9275 		r = 0;
9276 		vcpu->arch.complete_userspace_io = complete_emulated_mmio;
9277 	} else if (vcpu->arch.complete_userspace_io) {
9278 		writeback = false;
9279 		r = 0;
9280 	} else if (r == EMULATION_RESTART)
9281 		goto restart;
9282 	else
9283 		r = 1;
9284 
9285 writeback:
9286 	if (writeback) {
9287 		unsigned long rflags = static_call(kvm_x86_get_rflags)(vcpu);
9288 		toggle_interruptibility(vcpu, ctxt->interruptibility);
9289 		vcpu->arch.emulate_regs_need_sync_to_vcpu = false;
9290 
9291 		/*
9292 		 * Note, EXCPT_DB is assumed to be fault-like as the emulator
9293 		 * only supports code breakpoints and general detect #DB, both
9294 		 * of which are fault-like.
9295 		 */
9296 		if (!ctxt->have_exception ||
9297 		    exception_type(ctxt->exception.vector) == EXCPT_TRAP) {
9298 			kvm_pmu_trigger_event(vcpu, kvm_pmu_eventsel.INSTRUCTIONS_RETIRED);
9299 			if (ctxt->is_branch)
9300 				kvm_pmu_trigger_event(vcpu, kvm_pmu_eventsel.BRANCH_INSTRUCTIONS_RETIRED);
9301 			kvm_rip_write(vcpu, ctxt->eip);
9302 			if (r && (ctxt->tf || (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)))
9303 				r = kvm_vcpu_do_singlestep(vcpu);
9304 			static_call_cond(kvm_x86_update_emulated_instruction)(vcpu);
9305 			__kvm_set_rflags(vcpu, ctxt->eflags);
9306 		}
9307 
9308 		/*
9309 		 * For STI, interrupts are shadowed; so KVM_REQ_EVENT will
9310 		 * do nothing, and it will be requested again as soon as
9311 		 * the shadow expires.  But we still need to check here,
9312 		 * because POPF has no interrupt shadow.
9313 		 */
9314 		if (unlikely((ctxt->eflags & ~rflags) & X86_EFLAGS_IF))
9315 			kvm_make_request(KVM_REQ_EVENT, vcpu);
9316 	} else
9317 		vcpu->arch.emulate_regs_need_sync_to_vcpu = true;
9318 
9319 	return r;
9320 }
9321 
kvm_emulate_instruction(struct kvm_vcpu * vcpu,int emulation_type)9322 int kvm_emulate_instruction(struct kvm_vcpu *vcpu, int emulation_type)
9323 {
9324 	return x86_emulate_instruction(vcpu, 0, emulation_type, NULL, 0);
9325 }
9326 EXPORT_SYMBOL_GPL(kvm_emulate_instruction);
9327 
kvm_emulate_instruction_from_buffer(struct kvm_vcpu * vcpu,void * insn,int insn_len)9328 int kvm_emulate_instruction_from_buffer(struct kvm_vcpu *vcpu,
9329 					void *insn, int insn_len)
9330 {
9331 	return x86_emulate_instruction(vcpu, 0, 0, insn, insn_len);
9332 }
9333 EXPORT_SYMBOL_GPL(kvm_emulate_instruction_from_buffer);
9334 
complete_fast_pio_out_port_0x7e(struct kvm_vcpu * vcpu)9335 static int complete_fast_pio_out_port_0x7e(struct kvm_vcpu *vcpu)
9336 {
9337 	vcpu->arch.pio.count = 0;
9338 	return 1;
9339 }
9340 
complete_fast_pio_out(struct kvm_vcpu * vcpu)9341 static int complete_fast_pio_out(struct kvm_vcpu *vcpu)
9342 {
9343 	vcpu->arch.pio.count = 0;
9344 
9345 	if (unlikely(!kvm_is_linear_rip(vcpu, vcpu->arch.pio.linear_rip)))
9346 		return 1;
9347 
9348 	return kvm_skip_emulated_instruction(vcpu);
9349 }
9350 
kvm_fast_pio_out(struct kvm_vcpu * vcpu,int size,unsigned short port)9351 static int kvm_fast_pio_out(struct kvm_vcpu *vcpu, int size,
9352 			    unsigned short port)
9353 {
9354 	unsigned long val = kvm_rax_read(vcpu);
9355 	int ret = emulator_pio_out(vcpu, size, port, &val, 1);
9356 
9357 	if (ret)
9358 		return ret;
9359 
9360 	/*
9361 	 * Workaround userspace that relies on old KVM behavior of %rip being
9362 	 * incremented prior to exiting to userspace to handle "OUT 0x7e".
9363 	 */
9364 	if (port == 0x7e &&
9365 	    kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_OUT_7E_INC_RIP)) {
9366 		vcpu->arch.complete_userspace_io =
9367 			complete_fast_pio_out_port_0x7e;
9368 		kvm_skip_emulated_instruction(vcpu);
9369 	} else {
9370 		vcpu->arch.pio.linear_rip = kvm_get_linear_rip(vcpu);
9371 		vcpu->arch.complete_userspace_io = complete_fast_pio_out;
9372 	}
9373 	return 0;
9374 }
9375 
complete_fast_pio_in(struct kvm_vcpu * vcpu)9376 static int complete_fast_pio_in(struct kvm_vcpu *vcpu)
9377 {
9378 	unsigned long val;
9379 
9380 	/* We should only ever be called with arch.pio.count equal to 1 */
9381 	BUG_ON(vcpu->arch.pio.count != 1);
9382 
9383 	if (unlikely(!kvm_is_linear_rip(vcpu, vcpu->arch.pio.linear_rip))) {
9384 		vcpu->arch.pio.count = 0;
9385 		return 1;
9386 	}
9387 
9388 	/* For size less than 4 we merge, else we zero extend */
9389 	val = (vcpu->arch.pio.size < 4) ? kvm_rax_read(vcpu) : 0;
9390 
9391 	complete_emulator_pio_in(vcpu, &val);
9392 	kvm_rax_write(vcpu, val);
9393 
9394 	return kvm_skip_emulated_instruction(vcpu);
9395 }
9396 
kvm_fast_pio_in(struct kvm_vcpu * vcpu,int size,unsigned short port)9397 static int kvm_fast_pio_in(struct kvm_vcpu *vcpu, int size,
9398 			   unsigned short port)
9399 {
9400 	unsigned long val;
9401 	int ret;
9402 
9403 	/* For size less than 4 we merge, else we zero extend */
9404 	val = (size < 4) ? kvm_rax_read(vcpu) : 0;
9405 
9406 	ret = emulator_pio_in(vcpu, size, port, &val, 1);
9407 	if (ret) {
9408 		kvm_rax_write(vcpu, val);
9409 		return ret;
9410 	}
9411 
9412 	vcpu->arch.pio.linear_rip = kvm_get_linear_rip(vcpu);
9413 	vcpu->arch.complete_userspace_io = complete_fast_pio_in;
9414 
9415 	return 0;
9416 }
9417 
kvm_fast_pio(struct kvm_vcpu * vcpu,int size,unsigned short port,int in)9418 int kvm_fast_pio(struct kvm_vcpu *vcpu, int size, unsigned short port, int in)
9419 {
9420 	int ret;
9421 
9422 	if (in)
9423 		ret = kvm_fast_pio_in(vcpu, size, port);
9424 	else
9425 		ret = kvm_fast_pio_out(vcpu, size, port);
9426 	return ret && kvm_skip_emulated_instruction(vcpu);
9427 }
9428 EXPORT_SYMBOL_GPL(kvm_fast_pio);
9429 
kvmclock_cpu_down_prep(unsigned int cpu)9430 static int kvmclock_cpu_down_prep(unsigned int cpu)
9431 {
9432 	__this_cpu_write(cpu_tsc_khz, 0);
9433 	return 0;
9434 }
9435 
tsc_khz_changed(void * data)9436 static void tsc_khz_changed(void *data)
9437 {
9438 	struct cpufreq_freqs *freq = data;
9439 	unsigned long khz;
9440 
9441 	WARN_ON_ONCE(boot_cpu_has(X86_FEATURE_CONSTANT_TSC));
9442 
9443 	if (data)
9444 		khz = freq->new;
9445 	else
9446 		khz = cpufreq_quick_get(raw_smp_processor_id());
9447 	if (!khz)
9448 		khz = tsc_khz;
9449 	__this_cpu_write(cpu_tsc_khz, khz);
9450 }
9451 
9452 #ifdef CONFIG_X86_64
kvm_hyperv_tsc_notifier(void)9453 static void kvm_hyperv_tsc_notifier(void)
9454 {
9455 	struct kvm *kvm;
9456 	int cpu;
9457 
9458 	mutex_lock(&kvm_lock);
9459 	list_for_each_entry(kvm, &vm_list, vm_list)
9460 		kvm_make_mclock_inprogress_request(kvm);
9461 
9462 	/* no guest entries from this point */
9463 	hyperv_stop_tsc_emulation();
9464 
9465 	/* TSC frequency always matches when on Hyper-V */
9466 	if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
9467 		for_each_present_cpu(cpu)
9468 			per_cpu(cpu_tsc_khz, cpu) = tsc_khz;
9469 	}
9470 	kvm_caps.max_guest_tsc_khz = tsc_khz;
9471 
9472 	list_for_each_entry(kvm, &vm_list, vm_list) {
9473 		__kvm_start_pvclock_update(kvm);
9474 		pvclock_update_vm_gtod_copy(kvm);
9475 		kvm_end_pvclock_update(kvm);
9476 	}
9477 
9478 	mutex_unlock(&kvm_lock);
9479 }
9480 #endif
9481 
__kvmclock_cpufreq_notifier(struct cpufreq_freqs * freq,int cpu)9482 static void __kvmclock_cpufreq_notifier(struct cpufreq_freqs *freq, int cpu)
9483 {
9484 	struct kvm *kvm;
9485 	struct kvm_vcpu *vcpu;
9486 	int send_ipi = 0;
9487 	unsigned long i;
9488 
9489 	/*
9490 	 * We allow guests to temporarily run on slowing clocks,
9491 	 * provided we notify them after, or to run on accelerating
9492 	 * clocks, provided we notify them before.  Thus time never
9493 	 * goes backwards.
9494 	 *
9495 	 * However, we have a problem.  We can't atomically update
9496 	 * the frequency of a given CPU from this function; it is
9497 	 * merely a notifier, which can be called from any CPU.
9498 	 * Changing the TSC frequency at arbitrary points in time
9499 	 * requires a recomputation of local variables related to
9500 	 * the TSC for each VCPU.  We must flag these local variables
9501 	 * to be updated and be sure the update takes place with the
9502 	 * new frequency before any guests proceed.
9503 	 *
9504 	 * Unfortunately, the combination of hotplug CPU and frequency
9505 	 * change creates an intractable locking scenario; the order
9506 	 * of when these callouts happen is undefined with respect to
9507 	 * CPU hotplug, and they can race with each other.  As such,
9508 	 * merely setting per_cpu(cpu_tsc_khz) = X during a hotadd is
9509 	 * undefined; you can actually have a CPU frequency change take
9510 	 * place in between the computation of X and the setting of the
9511 	 * variable.  To protect against this problem, all updates of
9512 	 * the per_cpu tsc_khz variable are done in an interrupt
9513 	 * protected IPI, and all callers wishing to update the value
9514 	 * must wait for a synchronous IPI to complete (which is trivial
9515 	 * if the caller is on the CPU already).  This establishes the
9516 	 * necessary total order on variable updates.
9517 	 *
9518 	 * Note that because a guest time update may take place
9519 	 * anytime after the setting of the VCPU's request bit, the
9520 	 * correct TSC value must be set before the request.  However,
9521 	 * to ensure the update actually makes it to any guest which
9522 	 * starts running in hardware virtualization between the set
9523 	 * and the acquisition of the spinlock, we must also ping the
9524 	 * CPU after setting the request bit.
9525 	 *
9526 	 */
9527 
9528 	smp_call_function_single(cpu, tsc_khz_changed, freq, 1);
9529 
9530 	mutex_lock(&kvm_lock);
9531 	list_for_each_entry(kvm, &vm_list, vm_list) {
9532 		kvm_for_each_vcpu(i, vcpu, kvm) {
9533 			if (vcpu->cpu != cpu)
9534 				continue;
9535 			kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
9536 			if (vcpu->cpu != raw_smp_processor_id())
9537 				send_ipi = 1;
9538 		}
9539 	}
9540 	mutex_unlock(&kvm_lock);
9541 
9542 	if (freq->old < freq->new && send_ipi) {
9543 		/*
9544 		 * We upscale the frequency.  Must make the guest
9545 		 * doesn't see old kvmclock values while running with
9546 		 * the new frequency, otherwise we risk the guest sees
9547 		 * time go backwards.
9548 		 *
9549 		 * In case we update the frequency for another cpu
9550 		 * (which might be in guest context) send an interrupt
9551 		 * to kick the cpu out of guest context.  Next time
9552 		 * guest context is entered kvmclock will be updated,
9553 		 * so the guest will not see stale values.
9554 		 */
9555 		smp_call_function_single(cpu, tsc_khz_changed, freq, 1);
9556 	}
9557 }
9558 
kvmclock_cpufreq_notifier(struct notifier_block * nb,unsigned long val,void * data)9559 static int kvmclock_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
9560 				     void *data)
9561 {
9562 	struct cpufreq_freqs *freq = data;
9563 	int cpu;
9564 
9565 	if (val == CPUFREQ_PRECHANGE && freq->old > freq->new)
9566 		return 0;
9567 	if (val == CPUFREQ_POSTCHANGE && freq->old < freq->new)
9568 		return 0;
9569 
9570 	for_each_cpu(cpu, freq->policy->cpus)
9571 		__kvmclock_cpufreq_notifier(freq, cpu);
9572 
9573 	return 0;
9574 }
9575 
9576 static struct notifier_block kvmclock_cpufreq_notifier_block = {
9577 	.notifier_call  = kvmclock_cpufreq_notifier
9578 };
9579 
kvmclock_cpu_online(unsigned int cpu)9580 static int kvmclock_cpu_online(unsigned int cpu)
9581 {
9582 	tsc_khz_changed(NULL);
9583 	return 0;
9584 }
9585 
kvm_timer_init(void)9586 static void kvm_timer_init(void)
9587 {
9588 	if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
9589 		max_tsc_khz = tsc_khz;
9590 
9591 		if (IS_ENABLED(CONFIG_CPU_FREQ)) {
9592 			struct cpufreq_policy *policy;
9593 			int cpu;
9594 
9595 			cpu = get_cpu();
9596 			policy = cpufreq_cpu_get(cpu);
9597 			if (policy) {
9598 				if (policy->cpuinfo.max_freq)
9599 					max_tsc_khz = policy->cpuinfo.max_freq;
9600 				cpufreq_cpu_put(policy);
9601 			}
9602 			put_cpu();
9603 		}
9604 		cpufreq_register_notifier(&kvmclock_cpufreq_notifier_block,
9605 					  CPUFREQ_TRANSITION_NOTIFIER);
9606 
9607 		cpuhp_setup_state(CPUHP_AP_X86_KVM_CLK_ONLINE, "x86/kvm/clk:online",
9608 				  kvmclock_cpu_online, kvmclock_cpu_down_prep);
9609 	}
9610 }
9611 
9612 #ifdef CONFIG_X86_64
pvclock_gtod_update_fn(struct work_struct * work)9613 static void pvclock_gtod_update_fn(struct work_struct *work)
9614 {
9615 	struct kvm *kvm;
9616 	struct kvm_vcpu *vcpu;
9617 	unsigned long i;
9618 
9619 	mutex_lock(&kvm_lock);
9620 	list_for_each_entry(kvm, &vm_list, vm_list)
9621 		kvm_for_each_vcpu(i, vcpu, kvm)
9622 			kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
9623 	atomic_set(&kvm_guest_has_master_clock, 0);
9624 	mutex_unlock(&kvm_lock);
9625 }
9626 
9627 static DECLARE_WORK(pvclock_gtod_work, pvclock_gtod_update_fn);
9628 
9629 /*
9630  * Indirection to move queue_work() out of the tk_core.seq write held
9631  * region to prevent possible deadlocks against time accessors which
9632  * are invoked with work related locks held.
9633  */
pvclock_irq_work_fn(struct irq_work * w)9634 static void pvclock_irq_work_fn(struct irq_work *w)
9635 {
9636 	queue_work(system_long_wq, &pvclock_gtod_work);
9637 }
9638 
9639 static DEFINE_IRQ_WORK(pvclock_irq_work, pvclock_irq_work_fn);
9640 
9641 /*
9642  * Notification about pvclock gtod data update.
9643  */
pvclock_gtod_notify(struct notifier_block * nb,unsigned long unused,void * priv)9644 static int pvclock_gtod_notify(struct notifier_block *nb, unsigned long unused,
9645 			       void *priv)
9646 {
9647 	struct pvclock_gtod_data *gtod = &pvclock_gtod_data;
9648 	struct timekeeper *tk = priv;
9649 
9650 	update_pvclock_gtod(tk);
9651 
9652 	/*
9653 	 * Disable master clock if host does not trust, or does not use,
9654 	 * TSC based clocksource. Delegate queue_work() to irq_work as
9655 	 * this is invoked with tk_core.seq write held.
9656 	 */
9657 	if (!gtod_is_based_on_tsc(gtod->clock.vclock_mode) &&
9658 	    atomic_read(&kvm_guest_has_master_clock) != 0)
9659 		irq_work_queue(&pvclock_irq_work);
9660 	return 0;
9661 }
9662 
9663 static struct notifier_block pvclock_gtod_notifier = {
9664 	.notifier_call = pvclock_gtod_notify,
9665 };
9666 #endif
9667 
kvm_ops_update(struct kvm_x86_init_ops * ops)9668 static inline void kvm_ops_update(struct kvm_x86_init_ops *ops)
9669 {
9670 	memcpy(&kvm_x86_ops, ops->runtime_ops, sizeof(kvm_x86_ops));
9671 
9672 #define __KVM_X86_OP(func) \
9673 	static_call_update(kvm_x86_##func, kvm_x86_ops.func);
9674 #define KVM_X86_OP(func) \
9675 	WARN_ON(!kvm_x86_ops.func); __KVM_X86_OP(func)
9676 #define KVM_X86_OP_OPTIONAL __KVM_X86_OP
9677 #define KVM_X86_OP_OPTIONAL_RET0(func) \
9678 	static_call_update(kvm_x86_##func, (void *)kvm_x86_ops.func ? : \
9679 					   (void *)__static_call_return0);
9680 #include <asm/kvm-x86-ops.h>
9681 #undef __KVM_X86_OP
9682 
9683 	kvm_pmu_ops_update(ops->pmu_ops);
9684 }
9685 
kvm_x86_check_processor_compatibility(void)9686 static int kvm_x86_check_processor_compatibility(void)
9687 {
9688 	int cpu = smp_processor_id();
9689 	struct cpuinfo_x86 *c = &cpu_data(cpu);
9690 
9691 	/*
9692 	 * Compatibility checks are done when loading KVM and when enabling
9693 	 * hardware, e.g. during CPU hotplug, to ensure all online CPUs are
9694 	 * compatible, i.e. KVM should never perform a compatibility check on
9695 	 * an offline CPU.
9696 	 */
9697 	WARN_ON(!cpu_online(cpu));
9698 
9699 	if (__cr4_reserved_bits(cpu_has, c) !=
9700 	    __cr4_reserved_bits(cpu_has, &boot_cpu_data))
9701 		return -EIO;
9702 
9703 	return static_call(kvm_x86_check_processor_compatibility)();
9704 }
9705 
kvm_x86_check_cpu_compat(void * ret)9706 static void kvm_x86_check_cpu_compat(void *ret)
9707 {
9708 	*(int *)ret = kvm_x86_check_processor_compatibility();
9709 }
9710 
kvm_x86_vendor_init(struct kvm_x86_init_ops * ops)9711 int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
9712 {
9713 	u64 host_pat;
9714 	int r, cpu;
9715 
9716 	guard(mutex)(&vendor_module_lock);
9717 
9718 	if (kvm_x86_ops.hardware_enable) {
9719 		pr_err("already loaded vendor module '%s'\n", kvm_x86_ops.name);
9720 		return -EEXIST;
9721 	}
9722 
9723 	/*
9724 	 * KVM explicitly assumes that the guest has an FPU and
9725 	 * FXSAVE/FXRSTOR. For example, the KVM_GET_FPU explicitly casts the
9726 	 * vCPU's FPU state as a fxregs_state struct.
9727 	 */
9728 	if (!boot_cpu_has(X86_FEATURE_FPU) || !boot_cpu_has(X86_FEATURE_FXSR)) {
9729 		pr_err("inadequate fpu\n");
9730 		return -EOPNOTSUPP;
9731 	}
9732 
9733 	if (IS_ENABLED(CONFIG_PREEMPT_RT) && !boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
9734 		pr_err("RT requires X86_FEATURE_CONSTANT_TSC\n");
9735 		return -EOPNOTSUPP;
9736 	}
9737 
9738 	/*
9739 	 * KVM assumes that PAT entry '0' encodes WB memtype and simply zeroes
9740 	 * the PAT bits in SPTEs.  Bail if PAT[0] is programmed to something
9741 	 * other than WB.  Note, EPT doesn't utilize the PAT, but don't bother
9742 	 * with an exception.  PAT[0] is set to WB on RESET and also by the
9743 	 * kernel, i.e. failure indicates a kernel bug or broken firmware.
9744 	 */
9745 	if (rdmsrl_safe(MSR_IA32_CR_PAT, &host_pat) ||
9746 	    (host_pat & GENMASK(2, 0)) != 6) {
9747 		pr_err("host PAT[0] is not WB\n");
9748 		return -EIO;
9749 	}
9750 
9751 	memset(&kvm_caps, 0, sizeof(kvm_caps));
9752 
9753 	x86_emulator_cache = kvm_alloc_emulator_cache();
9754 	if (!x86_emulator_cache) {
9755 		pr_err("failed to allocate cache for x86 emulator\n");
9756 		return -ENOMEM;
9757 	}
9758 
9759 	user_return_msrs = alloc_percpu(struct kvm_user_return_msrs);
9760 	if (!user_return_msrs) {
9761 		pr_err("failed to allocate percpu kvm_user_return_msrs\n");
9762 		r = -ENOMEM;
9763 		goto out_free_x86_emulator_cache;
9764 	}
9765 	kvm_nr_uret_msrs = 0;
9766 
9767 	r = kvm_mmu_vendor_module_init();
9768 	if (r)
9769 		goto out_free_percpu;
9770 
9771 	kvm_caps.supported_vm_types = BIT(KVM_X86_DEFAULT_VM);
9772 	kvm_caps.supported_mce_cap = MCG_CTL_P | MCG_SER_P;
9773 
9774 	if (boot_cpu_has(X86_FEATURE_XSAVE)) {
9775 		host_xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
9776 		kvm_caps.supported_xcr0 = host_xcr0 & KVM_SUPPORTED_XCR0;
9777 	}
9778 
9779 	rdmsrl_safe(MSR_EFER, &host_efer);
9780 
9781 	if (boot_cpu_has(X86_FEATURE_XSAVES))
9782 		rdmsrl(MSR_IA32_XSS, host_xss);
9783 
9784 	kvm_init_pmu_capability(ops->pmu_ops);
9785 
9786 	if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES))
9787 		rdmsrl(MSR_IA32_ARCH_CAPABILITIES, host_arch_capabilities);
9788 
9789 	r = ops->hardware_setup();
9790 	if (r != 0)
9791 		goto out_mmu_exit;
9792 
9793 	kvm_ops_update(ops);
9794 
9795 	for_each_online_cpu(cpu) {
9796 		smp_call_function_single(cpu, kvm_x86_check_cpu_compat, &r, 1);
9797 		if (r < 0)
9798 			goto out_unwind_ops;
9799 	}
9800 
9801 	/*
9802 	 * Point of no return!  DO NOT add error paths below this point unless
9803 	 * absolutely necessary, as most operations from this point forward
9804 	 * require unwinding.
9805 	 */
9806 	kvm_timer_init();
9807 
9808 	if (pi_inject_timer == -1)
9809 		pi_inject_timer = housekeeping_enabled(HK_TYPE_TIMER);
9810 #ifdef CONFIG_X86_64
9811 	pvclock_gtod_register_notifier(&pvclock_gtod_notifier);
9812 
9813 	if (hypervisor_is_type(X86_HYPER_MS_HYPERV))
9814 		set_hv_tscchange_cb(kvm_hyperv_tsc_notifier);
9815 #endif
9816 
9817 	kvm_register_perf_callbacks(ops->handle_intel_pt_intr);
9818 
9819 	if (IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_mmu_enabled)
9820 		kvm_caps.supported_vm_types |= BIT(KVM_X86_SW_PROTECTED_VM);
9821 
9822 	if (!kvm_cpu_cap_has(X86_FEATURE_XSAVES))
9823 		kvm_caps.supported_xss = 0;
9824 
9825 #define __kvm_cpu_cap_has(UNUSED_, f) kvm_cpu_cap_has(f)
9826 	cr4_reserved_bits = __cr4_reserved_bits(__kvm_cpu_cap_has, UNUSED_);
9827 #undef __kvm_cpu_cap_has
9828 
9829 	if (kvm_caps.has_tsc_control) {
9830 		/*
9831 		 * Make sure the user can only configure tsc_khz values that
9832 		 * fit into a signed integer.
9833 		 * A min value is not calculated because it will always
9834 		 * be 1 on all machines.
9835 		 */
9836 		u64 max = min(0x7fffffffULL,
9837 			      __scale_tsc(kvm_caps.max_tsc_scaling_ratio, tsc_khz));
9838 		kvm_caps.max_guest_tsc_khz = max;
9839 	}
9840 	kvm_caps.default_tsc_scaling_ratio = 1ULL << kvm_caps.tsc_scaling_ratio_frac_bits;
9841 	kvm_init_msr_lists();
9842 	return 0;
9843 
9844 out_unwind_ops:
9845 	kvm_x86_ops.hardware_enable = NULL;
9846 	static_call(kvm_x86_hardware_unsetup)();
9847 out_mmu_exit:
9848 	kvm_mmu_vendor_module_exit();
9849 out_free_percpu:
9850 	free_percpu(user_return_msrs);
9851 out_free_x86_emulator_cache:
9852 	kmem_cache_destroy(x86_emulator_cache);
9853 	return r;
9854 }
9855 EXPORT_SYMBOL_GPL(kvm_x86_vendor_init);
9856 
kvm_x86_vendor_exit(void)9857 void kvm_x86_vendor_exit(void)
9858 {
9859 	kvm_unregister_perf_callbacks();
9860 
9861 #ifdef CONFIG_X86_64
9862 	if (hypervisor_is_type(X86_HYPER_MS_HYPERV))
9863 		clear_hv_tscchange_cb();
9864 #endif
9865 	kvm_lapic_exit();
9866 
9867 	if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) {
9868 		cpufreq_unregister_notifier(&kvmclock_cpufreq_notifier_block,
9869 					    CPUFREQ_TRANSITION_NOTIFIER);
9870 		cpuhp_remove_state_nocalls(CPUHP_AP_X86_KVM_CLK_ONLINE);
9871 	}
9872 #ifdef CONFIG_X86_64
9873 	pvclock_gtod_unregister_notifier(&pvclock_gtod_notifier);
9874 	irq_work_sync(&pvclock_irq_work);
9875 	cancel_work_sync(&pvclock_gtod_work);
9876 #endif
9877 	static_call(kvm_x86_hardware_unsetup)();
9878 	kvm_mmu_vendor_module_exit();
9879 	free_percpu(user_return_msrs);
9880 	kmem_cache_destroy(x86_emulator_cache);
9881 #ifdef CONFIG_KVM_XEN
9882 	static_key_deferred_flush(&kvm_xen_enabled);
9883 	WARN_ON(static_branch_unlikely(&kvm_xen_enabled.key));
9884 #endif
9885 	mutex_lock(&vendor_module_lock);
9886 	kvm_x86_ops.hardware_enable = NULL;
9887 	mutex_unlock(&vendor_module_lock);
9888 }
9889 EXPORT_SYMBOL_GPL(kvm_x86_vendor_exit);
9890 
__kvm_emulate_halt(struct kvm_vcpu * vcpu,int state,int reason)9891 static int __kvm_emulate_halt(struct kvm_vcpu *vcpu, int state, int reason)
9892 {
9893 	/*
9894 	 * The vCPU has halted, e.g. executed HLT.  Update the run state if the
9895 	 * local APIC is in-kernel, the run loop will detect the non-runnable
9896 	 * state and halt the vCPU.  Exit to userspace if the local APIC is
9897 	 * managed by userspace, in which case userspace is responsible for
9898 	 * handling wake events.
9899 	 */
9900 	++vcpu->stat.halt_exits;
9901 	if (lapic_in_kernel(vcpu)) {
9902 		vcpu->arch.mp_state = state;
9903 		return 1;
9904 	} else {
9905 		vcpu->run->exit_reason = reason;
9906 		return 0;
9907 	}
9908 }
9909 
kvm_emulate_halt_noskip(struct kvm_vcpu * vcpu)9910 int kvm_emulate_halt_noskip(struct kvm_vcpu *vcpu)
9911 {
9912 	return __kvm_emulate_halt(vcpu, KVM_MP_STATE_HALTED, KVM_EXIT_HLT);
9913 }
9914 EXPORT_SYMBOL_GPL(kvm_emulate_halt_noskip);
9915 
kvm_emulate_halt(struct kvm_vcpu * vcpu)9916 int kvm_emulate_halt(struct kvm_vcpu *vcpu)
9917 {
9918 	int ret = kvm_skip_emulated_instruction(vcpu);
9919 	/*
9920 	 * TODO: we might be squashing a GUESTDBG_SINGLESTEP-triggered
9921 	 * KVM_EXIT_DEBUG here.
9922 	 */
9923 	return kvm_emulate_halt_noskip(vcpu) && ret;
9924 }
9925 EXPORT_SYMBOL_GPL(kvm_emulate_halt);
9926 
kvm_emulate_ap_reset_hold(struct kvm_vcpu * vcpu)9927 int kvm_emulate_ap_reset_hold(struct kvm_vcpu *vcpu)
9928 {
9929 	int ret = kvm_skip_emulated_instruction(vcpu);
9930 
9931 	return __kvm_emulate_halt(vcpu, KVM_MP_STATE_AP_RESET_HOLD,
9932 					KVM_EXIT_AP_RESET_HOLD) && ret;
9933 }
9934 EXPORT_SYMBOL_GPL(kvm_emulate_ap_reset_hold);
9935 
9936 #ifdef CONFIG_X86_64
kvm_pv_clock_pairing(struct kvm_vcpu * vcpu,gpa_t paddr,unsigned long clock_type)9937 static int kvm_pv_clock_pairing(struct kvm_vcpu *vcpu, gpa_t paddr,
9938 			        unsigned long clock_type)
9939 {
9940 	struct kvm_clock_pairing clock_pairing;
9941 	struct timespec64 ts;
9942 	u64 cycle;
9943 	int ret;
9944 
9945 	if (clock_type != KVM_CLOCK_PAIRING_WALLCLOCK)
9946 		return -KVM_EOPNOTSUPP;
9947 
9948 	/*
9949 	 * When tsc is in permanent catchup mode guests won't be able to use
9950 	 * pvclock_read_retry loop to get consistent view of pvclock
9951 	 */
9952 	if (vcpu->arch.tsc_always_catchup)
9953 		return -KVM_EOPNOTSUPP;
9954 
9955 	if (!kvm_get_walltime_and_clockread(&ts, &cycle))
9956 		return -KVM_EOPNOTSUPP;
9957 
9958 	clock_pairing.sec = ts.tv_sec;
9959 	clock_pairing.nsec = ts.tv_nsec;
9960 	clock_pairing.tsc = kvm_read_l1_tsc(vcpu, cycle);
9961 	clock_pairing.flags = 0;
9962 	memset(&clock_pairing.pad, 0, sizeof(clock_pairing.pad));
9963 
9964 	ret = 0;
9965 	if (kvm_write_guest(vcpu->kvm, paddr, &clock_pairing,
9966 			    sizeof(struct kvm_clock_pairing)))
9967 		ret = -KVM_EFAULT;
9968 
9969 	return ret;
9970 }
9971 #endif
9972 
9973 /*
9974  * kvm_pv_kick_cpu_op:  Kick a vcpu.
9975  *
9976  * @apicid - apicid of vcpu to be kicked.
9977  */
kvm_pv_kick_cpu_op(struct kvm * kvm,int apicid)9978 static void kvm_pv_kick_cpu_op(struct kvm *kvm, int apicid)
9979 {
9980 	/*
9981 	 * All other fields are unused for APIC_DM_REMRD, but may be consumed by
9982 	 * common code, e.g. for tracing. Defer initialization to the compiler.
9983 	 */
9984 	struct kvm_lapic_irq lapic_irq = {
9985 		.delivery_mode = APIC_DM_REMRD,
9986 		.dest_mode = APIC_DEST_PHYSICAL,
9987 		.shorthand = APIC_DEST_NOSHORT,
9988 		.dest_id = apicid,
9989 	};
9990 
9991 	kvm_irq_delivery_to_apic(kvm, NULL, &lapic_irq, NULL);
9992 }
9993 
kvm_apicv_activated(struct kvm * kvm)9994 bool kvm_apicv_activated(struct kvm *kvm)
9995 {
9996 	return (READ_ONCE(kvm->arch.apicv_inhibit_reasons) == 0);
9997 }
9998 EXPORT_SYMBOL_GPL(kvm_apicv_activated);
9999 
kvm_vcpu_apicv_activated(struct kvm_vcpu * vcpu)10000 bool kvm_vcpu_apicv_activated(struct kvm_vcpu *vcpu)
10001 {
10002 	ulong vm_reasons = READ_ONCE(vcpu->kvm->arch.apicv_inhibit_reasons);
10003 	ulong vcpu_reasons = static_call(kvm_x86_vcpu_get_apicv_inhibit_reasons)(vcpu);
10004 
10005 	return (vm_reasons | vcpu_reasons) == 0;
10006 }
10007 EXPORT_SYMBOL_GPL(kvm_vcpu_apicv_activated);
10008 
set_or_clear_apicv_inhibit(unsigned long * inhibits,enum kvm_apicv_inhibit reason,bool set)10009 static void set_or_clear_apicv_inhibit(unsigned long *inhibits,
10010 				       enum kvm_apicv_inhibit reason, bool set)
10011 {
10012 	if (set)
10013 		__set_bit(reason, inhibits);
10014 	else
10015 		__clear_bit(reason, inhibits);
10016 
10017 	trace_kvm_apicv_inhibit_changed(reason, set, *inhibits);
10018 }
10019 
kvm_apicv_init(struct kvm * kvm)10020 static void kvm_apicv_init(struct kvm *kvm)
10021 {
10022 	enum kvm_apicv_inhibit reason = enable_apicv ? APICV_INHIBIT_REASON_ABSENT :
10023 						       APICV_INHIBIT_REASON_DISABLE;
10024 
10025 	set_or_clear_apicv_inhibit(&kvm->arch.apicv_inhibit_reasons, reason, true);
10026 
10027 	init_rwsem(&kvm->arch.apicv_update_lock);
10028 }
10029 
kvm_sched_yield(struct kvm_vcpu * vcpu,unsigned long dest_id)10030 static void kvm_sched_yield(struct kvm_vcpu *vcpu, unsigned long dest_id)
10031 {
10032 	struct kvm_vcpu *target = NULL;
10033 	struct kvm_apic_map *map;
10034 
10035 	vcpu->stat.directed_yield_attempted++;
10036 
10037 	if (single_task_running())
10038 		goto no_yield;
10039 
10040 	rcu_read_lock();
10041 	map = rcu_dereference(vcpu->kvm->arch.apic_map);
10042 
10043 	if (likely(map) && dest_id <= map->max_apic_id && map->phys_map[dest_id])
10044 		target = map->phys_map[dest_id]->vcpu;
10045 
10046 	rcu_read_unlock();
10047 
10048 	if (!target || !READ_ONCE(target->ready))
10049 		goto no_yield;
10050 
10051 	/* Ignore requests to yield to self */
10052 	if (vcpu == target)
10053 		goto no_yield;
10054 
10055 	if (kvm_vcpu_yield_to(target) <= 0)
10056 		goto no_yield;
10057 
10058 	vcpu->stat.directed_yield_successful++;
10059 
10060 no_yield:
10061 	return;
10062 }
10063 
complete_hypercall_exit(struct kvm_vcpu * vcpu)10064 static int complete_hypercall_exit(struct kvm_vcpu *vcpu)
10065 {
10066 	u64 ret = vcpu->run->hypercall.ret;
10067 
10068 	if (!is_64_bit_mode(vcpu))
10069 		ret = (u32)ret;
10070 	kvm_rax_write(vcpu, ret);
10071 	++vcpu->stat.hypercalls;
10072 	return kvm_skip_emulated_instruction(vcpu);
10073 }
10074 
__kvm_emulate_hypercall(struct kvm_vcpu * vcpu,unsigned long nr,unsigned long a0,unsigned long a1,unsigned long a2,unsigned long a3,int op_64_bit,int cpl)10075 unsigned long __kvm_emulate_hypercall(struct kvm_vcpu *vcpu, unsigned long nr,
10076 				      unsigned long a0, unsigned long a1,
10077 				      unsigned long a2, unsigned long a3,
10078 				      int op_64_bit, int cpl)
10079 {
10080 	unsigned long ret;
10081 
10082 	trace_kvm_hypercall(nr, a0, a1, a2, a3);
10083 
10084 	if (!op_64_bit) {
10085 		nr &= 0xFFFFFFFF;
10086 		a0 &= 0xFFFFFFFF;
10087 		a1 &= 0xFFFFFFFF;
10088 		a2 &= 0xFFFFFFFF;
10089 		a3 &= 0xFFFFFFFF;
10090 	}
10091 
10092 	if (cpl) {
10093 		ret = -KVM_EPERM;
10094 		goto out;
10095 	}
10096 
10097 	ret = -KVM_ENOSYS;
10098 
10099 	switch (nr) {
10100 	case KVM_HC_VAPIC_POLL_IRQ:
10101 		ret = 0;
10102 		break;
10103 	case KVM_HC_KICK_CPU:
10104 		if (!guest_pv_has(vcpu, KVM_FEATURE_PV_UNHALT))
10105 			break;
10106 
10107 		kvm_pv_kick_cpu_op(vcpu->kvm, a1);
10108 		kvm_sched_yield(vcpu, a1);
10109 		ret = 0;
10110 		break;
10111 #ifdef CONFIG_X86_64
10112 	case KVM_HC_CLOCK_PAIRING:
10113 		ret = kvm_pv_clock_pairing(vcpu, a0, a1);
10114 		break;
10115 #endif
10116 	case KVM_HC_SEND_IPI:
10117 		if (!guest_pv_has(vcpu, KVM_FEATURE_PV_SEND_IPI))
10118 			break;
10119 
10120 		ret = kvm_pv_send_ipi(vcpu->kvm, a0, a1, a2, a3, op_64_bit);
10121 		break;
10122 	case KVM_HC_SCHED_YIELD:
10123 		if (!guest_pv_has(vcpu, KVM_FEATURE_PV_SCHED_YIELD))
10124 			break;
10125 
10126 		kvm_sched_yield(vcpu, a0);
10127 		ret = 0;
10128 		break;
10129 	case KVM_HC_MAP_GPA_RANGE: {
10130 		u64 gpa = a0, npages = a1, attrs = a2;
10131 
10132 		ret = -KVM_ENOSYS;
10133 		if (!(vcpu->kvm->arch.hypercall_exit_enabled & (1 << KVM_HC_MAP_GPA_RANGE)))
10134 			break;
10135 
10136 		if (!PAGE_ALIGNED(gpa) || !npages ||
10137 		    gpa_to_gfn(gpa) + npages <= gpa_to_gfn(gpa)) {
10138 			ret = -KVM_EINVAL;
10139 			break;
10140 		}
10141 
10142 		vcpu->run->exit_reason        = KVM_EXIT_HYPERCALL;
10143 		vcpu->run->hypercall.nr       = KVM_HC_MAP_GPA_RANGE;
10144 		vcpu->run->hypercall.args[0]  = gpa;
10145 		vcpu->run->hypercall.args[1]  = npages;
10146 		vcpu->run->hypercall.args[2]  = attrs;
10147 		vcpu->run->hypercall.flags    = 0;
10148 		if (op_64_bit)
10149 			vcpu->run->hypercall.flags |= KVM_EXIT_HYPERCALL_LONG_MODE;
10150 
10151 		WARN_ON_ONCE(vcpu->run->hypercall.flags & KVM_EXIT_HYPERCALL_MBZ);
10152 		vcpu->arch.complete_userspace_io = complete_hypercall_exit;
10153 		/* stat is incremented on completion. */
10154 		return 0;
10155 	}
10156 	default:
10157 		ret = -KVM_ENOSYS;
10158 		break;
10159 	}
10160 
10161 out:
10162 	++vcpu->stat.hypercalls;
10163 	return ret;
10164 }
10165 EXPORT_SYMBOL_GPL(__kvm_emulate_hypercall);
10166 
kvm_emulate_hypercall(struct kvm_vcpu * vcpu)10167 int kvm_emulate_hypercall(struct kvm_vcpu *vcpu)
10168 {
10169 	unsigned long nr, a0, a1, a2, a3, ret;
10170 	int op_64_bit;
10171 	int cpl;
10172 
10173 	if (kvm_xen_hypercall_enabled(vcpu->kvm))
10174 		return kvm_xen_hypercall(vcpu);
10175 
10176 	if (kvm_hv_hypercall_enabled(vcpu))
10177 		return kvm_hv_hypercall(vcpu);
10178 
10179 	nr = kvm_rax_read(vcpu);
10180 	a0 = kvm_rbx_read(vcpu);
10181 	a1 = kvm_rcx_read(vcpu);
10182 	a2 = kvm_rdx_read(vcpu);
10183 	a3 = kvm_rsi_read(vcpu);
10184 	op_64_bit = is_64_bit_hypercall(vcpu);
10185 	cpl = static_call(kvm_x86_get_cpl)(vcpu);
10186 
10187 	ret = __kvm_emulate_hypercall(vcpu, nr, a0, a1, a2, a3, op_64_bit, cpl);
10188 	if (nr == KVM_HC_MAP_GPA_RANGE && !ret)
10189 		/* MAP_GPA tosses the request to the user space. */
10190 		return 0;
10191 
10192 	if (!op_64_bit)
10193 		ret = (u32)ret;
10194 	kvm_rax_write(vcpu, ret);
10195 
10196 	return kvm_skip_emulated_instruction(vcpu);
10197 }
10198 EXPORT_SYMBOL_GPL(kvm_emulate_hypercall);
10199 
emulator_fix_hypercall(struct x86_emulate_ctxt * ctxt)10200 static int emulator_fix_hypercall(struct x86_emulate_ctxt *ctxt)
10201 {
10202 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
10203 	char instruction[3];
10204 	unsigned long rip = kvm_rip_read(vcpu);
10205 
10206 	/*
10207 	 * If the quirk is disabled, synthesize a #UD and let the guest pick up
10208 	 * the pieces.
10209 	 */
10210 	if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_FIX_HYPERCALL_INSN)) {
10211 		ctxt->exception.error_code_valid = false;
10212 		ctxt->exception.vector = UD_VECTOR;
10213 		ctxt->have_exception = true;
10214 		return X86EMUL_PROPAGATE_FAULT;
10215 	}
10216 
10217 	static_call(kvm_x86_patch_hypercall)(vcpu, instruction);
10218 
10219 	return emulator_write_emulated(ctxt, rip, instruction, 3,
10220 		&ctxt->exception);
10221 }
10222 
dm_request_for_irq_injection(struct kvm_vcpu * vcpu)10223 static int dm_request_for_irq_injection(struct kvm_vcpu *vcpu)
10224 {
10225 	return vcpu->run->request_interrupt_window &&
10226 		likely(!pic_in_kernel(vcpu->kvm));
10227 }
10228 
10229 /* Called within kvm->srcu read side.  */
post_kvm_run_save(struct kvm_vcpu * vcpu)10230 static void post_kvm_run_save(struct kvm_vcpu *vcpu)
10231 {
10232 	struct kvm_run *kvm_run = vcpu->run;
10233 
10234 	kvm_run->if_flag = static_call(kvm_x86_get_if_flag)(vcpu);
10235 	kvm_run->cr8 = kvm_get_cr8(vcpu);
10236 	kvm_run->apic_base = kvm_get_apic_base(vcpu);
10237 
10238 	kvm_run->ready_for_interrupt_injection =
10239 		pic_in_kernel(vcpu->kvm) ||
10240 		kvm_vcpu_ready_for_interrupt_injection(vcpu);
10241 
10242 	if (is_smm(vcpu))
10243 		kvm_run->flags |= KVM_RUN_X86_SMM;
10244 }
10245 
update_cr8_intercept(struct kvm_vcpu * vcpu)10246 static void update_cr8_intercept(struct kvm_vcpu *vcpu)
10247 {
10248 	int max_irr, tpr;
10249 
10250 	if (!kvm_x86_ops.update_cr8_intercept)
10251 		return;
10252 
10253 	if (!lapic_in_kernel(vcpu))
10254 		return;
10255 
10256 	if (vcpu->arch.apic->apicv_active)
10257 		return;
10258 
10259 	if (!vcpu->arch.apic->vapic_addr)
10260 		max_irr = kvm_lapic_find_highest_irr(vcpu);
10261 	else
10262 		max_irr = -1;
10263 
10264 	if (max_irr != -1)
10265 		max_irr >>= 4;
10266 
10267 	tpr = kvm_lapic_get_cr8(vcpu);
10268 
10269 	static_call(kvm_x86_update_cr8_intercept)(vcpu, tpr, max_irr);
10270 }
10271 
10272 
kvm_check_nested_events(struct kvm_vcpu * vcpu)10273 int kvm_check_nested_events(struct kvm_vcpu *vcpu)
10274 {
10275 	if (kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu)) {
10276 		kvm_x86_ops.nested_ops->triple_fault(vcpu);
10277 		return 1;
10278 	}
10279 
10280 	return kvm_x86_ops.nested_ops->check_events(vcpu);
10281 }
10282 
kvm_inject_exception(struct kvm_vcpu * vcpu)10283 static void kvm_inject_exception(struct kvm_vcpu *vcpu)
10284 {
10285 	/*
10286 	 * Suppress the error code if the vCPU is in Real Mode, as Real Mode
10287 	 * exceptions don't report error codes.  The presence of an error code
10288 	 * is carried with the exception and only stripped when the exception
10289 	 * is injected as intercepted #PF VM-Exits for AMD's Paged Real Mode do
10290 	 * report an error code despite the CPU being in Real Mode.
10291 	 */
10292 	vcpu->arch.exception.has_error_code &= is_protmode(vcpu);
10293 
10294 	trace_kvm_inj_exception(vcpu->arch.exception.vector,
10295 				vcpu->arch.exception.has_error_code,
10296 				vcpu->arch.exception.error_code,
10297 				vcpu->arch.exception.injected);
10298 
10299 	static_call(kvm_x86_inject_exception)(vcpu);
10300 }
10301 
10302 /*
10303  * Check for any event (interrupt or exception) that is ready to be injected,
10304  * and if there is at least one event, inject the event with the highest
10305  * priority.  This handles both "pending" events, i.e. events that have never
10306  * been injected into the guest, and "injected" events, i.e. events that were
10307  * injected as part of a previous VM-Enter, but weren't successfully delivered
10308  * and need to be re-injected.
10309  *
10310  * Note, this is not guaranteed to be invoked on a guest instruction boundary,
10311  * i.e. doesn't guarantee that there's an event window in the guest.  KVM must
10312  * be able to inject exceptions in the "middle" of an instruction, and so must
10313  * also be able to re-inject NMIs and IRQs in the middle of an instruction.
10314  * I.e. for exceptions and re-injected events, NOT invoking this on instruction
10315  * boundaries is necessary and correct.
10316  *
10317  * For simplicity, KVM uses a single path to inject all events (except events
10318  * that are injected directly from L1 to L2) and doesn't explicitly track
10319  * instruction boundaries for asynchronous events.  However, because VM-Exits
10320  * that can occur during instruction execution typically result in KVM skipping
10321  * the instruction or injecting an exception, e.g. instruction and exception
10322  * intercepts, and because pending exceptions have higher priority than pending
10323  * interrupts, KVM still honors instruction boundaries in most scenarios.
10324  *
10325  * But, if a VM-Exit occurs during instruction execution, and KVM does NOT skip
10326  * the instruction or inject an exception, then KVM can incorrecty inject a new
10327  * asynchronous event if the event became pending after the CPU fetched the
10328  * instruction (in the guest).  E.g. if a page fault (#PF, #NPF, EPT violation)
10329  * occurs and is resolved by KVM, a coincident NMI, SMI, IRQ, etc... can be
10330  * injected on the restarted instruction instead of being deferred until the
10331  * instruction completes.
10332  *
10333  * In practice, this virtualization hole is unlikely to be observed by the
10334  * guest, and even less likely to cause functional problems.  To detect the
10335  * hole, the guest would have to trigger an event on a side effect of an early
10336  * phase of instruction execution, e.g. on the instruction fetch from memory.
10337  * And for it to be a functional problem, the guest would need to depend on the
10338  * ordering between that side effect, the instruction completing, _and_ the
10339  * delivery of the asynchronous event.
10340  */
kvm_check_and_inject_events(struct kvm_vcpu * vcpu,bool * req_immediate_exit)10341 static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
10342 				       bool *req_immediate_exit)
10343 {
10344 	bool can_inject;
10345 	int r;
10346 
10347 	/*
10348 	 * Process nested events first, as nested VM-Exit supersedes event
10349 	 * re-injection.  If there's an event queued for re-injection, it will
10350 	 * be saved into the appropriate vmc{b,s}12 fields on nested VM-Exit.
10351 	 */
10352 	if (is_guest_mode(vcpu))
10353 		r = kvm_check_nested_events(vcpu);
10354 	else
10355 		r = 0;
10356 
10357 	/*
10358 	 * Re-inject exceptions and events *especially* if immediate entry+exit
10359 	 * to/from L2 is needed, as any event that has already been injected
10360 	 * into L2 needs to complete its lifecycle before injecting a new event.
10361 	 *
10362 	 * Don't re-inject an NMI or interrupt if there is a pending exception.
10363 	 * This collision arises if an exception occurred while vectoring the
10364 	 * injected event, KVM intercepted said exception, and KVM ultimately
10365 	 * determined the fault belongs to the guest and queues the exception
10366 	 * for injection back into the guest.
10367 	 *
10368 	 * "Injected" interrupts can also collide with pending exceptions if
10369 	 * userspace ignores the "ready for injection" flag and blindly queues
10370 	 * an interrupt.  In that case, prioritizing the exception is correct,
10371 	 * as the exception "occurred" before the exit to userspace.  Trap-like
10372 	 * exceptions, e.g. most #DBs, have higher priority than interrupts.
10373 	 * And while fault-like exceptions, e.g. #GP and #PF, are the lowest
10374 	 * priority, they're only generated (pended) during instruction
10375 	 * execution, and interrupts are recognized at instruction boundaries.
10376 	 * Thus a pending fault-like exception means the fault occurred on the
10377 	 * *previous* instruction and must be serviced prior to recognizing any
10378 	 * new events in order to fully complete the previous instruction.
10379 	 */
10380 	if (vcpu->arch.exception.injected)
10381 		kvm_inject_exception(vcpu);
10382 	else if (kvm_is_exception_pending(vcpu))
10383 		; /* see above */
10384 	else if (vcpu->arch.nmi_injected)
10385 		static_call(kvm_x86_inject_nmi)(vcpu);
10386 	else if (vcpu->arch.interrupt.injected)
10387 		static_call(kvm_x86_inject_irq)(vcpu, true);
10388 
10389 	/*
10390 	 * Exceptions that morph to VM-Exits are handled above, and pending
10391 	 * exceptions on top of injected exceptions that do not VM-Exit should
10392 	 * either morph to #DF or, sadly, override the injected exception.
10393 	 */
10394 	WARN_ON_ONCE(vcpu->arch.exception.injected &&
10395 		     vcpu->arch.exception.pending);
10396 
10397 	/*
10398 	 * Bail if immediate entry+exit to/from the guest is needed to complete
10399 	 * nested VM-Enter or event re-injection so that a different pending
10400 	 * event can be serviced (or if KVM needs to exit to userspace).
10401 	 *
10402 	 * Otherwise, continue processing events even if VM-Exit occurred.  The
10403 	 * VM-Exit will have cleared exceptions that were meant for L2, but
10404 	 * there may now be events that can be injected into L1.
10405 	 */
10406 	if (r < 0)
10407 		goto out;
10408 
10409 	/*
10410 	 * A pending exception VM-Exit should either result in nested VM-Exit
10411 	 * or force an immediate re-entry and exit to/from L2, and exception
10412 	 * VM-Exits cannot be injected (flag should _never_ be set).
10413 	 */
10414 	WARN_ON_ONCE(vcpu->arch.exception_vmexit.injected ||
10415 		     vcpu->arch.exception_vmexit.pending);
10416 
10417 	/*
10418 	 * New events, other than exceptions, cannot be injected if KVM needs
10419 	 * to re-inject a previous event.  See above comments on re-injecting
10420 	 * for why pending exceptions get priority.
10421 	 */
10422 	can_inject = !kvm_event_needs_reinjection(vcpu);
10423 
10424 	if (vcpu->arch.exception.pending) {
10425 		/*
10426 		 * Fault-class exceptions, except #DBs, set RF=1 in the RFLAGS
10427 		 * value pushed on the stack.  Trap-like exception and all #DBs
10428 		 * leave RF as-is (KVM follows Intel's behavior in this regard;
10429 		 * AMD states that code breakpoint #DBs excplitly clear RF=0).
10430 		 *
10431 		 * Note, most versions of Intel's SDM and AMD's APM incorrectly
10432 		 * describe the behavior of General Detect #DBs, which are
10433 		 * fault-like.  They do _not_ set RF, a la code breakpoints.
10434 		 */
10435 		if (exception_type(vcpu->arch.exception.vector) == EXCPT_FAULT)
10436 			__kvm_set_rflags(vcpu, kvm_get_rflags(vcpu) |
10437 					     X86_EFLAGS_RF);
10438 
10439 		if (vcpu->arch.exception.vector == DB_VECTOR) {
10440 			kvm_deliver_exception_payload(vcpu, &vcpu->arch.exception);
10441 			if (vcpu->arch.dr7 & DR7_GD) {
10442 				vcpu->arch.dr7 &= ~DR7_GD;
10443 				kvm_update_dr7(vcpu);
10444 			}
10445 		}
10446 
10447 		kvm_inject_exception(vcpu);
10448 
10449 		vcpu->arch.exception.pending = false;
10450 		vcpu->arch.exception.injected = true;
10451 
10452 		can_inject = false;
10453 	}
10454 
10455 	/* Don't inject interrupts if the user asked to avoid doing so */
10456 	if (vcpu->guest_debug & KVM_GUESTDBG_BLOCKIRQ)
10457 		return 0;
10458 
10459 	/*
10460 	 * Finally, inject interrupt events.  If an event cannot be injected
10461 	 * due to architectural conditions (e.g. IF=0) a window-open exit
10462 	 * will re-request KVM_REQ_EVENT.  Sometimes however an event is pending
10463 	 * and can architecturally be injected, but we cannot do it right now:
10464 	 * an interrupt could have arrived just now and we have to inject it
10465 	 * as a vmexit, or there could already an event in the queue, which is
10466 	 * indicated by can_inject.  In that case we request an immediate exit
10467 	 * in order to make progress and get back here for another iteration.
10468 	 * The kvm_x86_ops hooks communicate this by returning -EBUSY.
10469 	 */
10470 #ifdef CONFIG_KVM_SMM
10471 	if (vcpu->arch.smi_pending) {
10472 		r = can_inject ? static_call(kvm_x86_smi_allowed)(vcpu, true) : -EBUSY;
10473 		if (r < 0)
10474 			goto out;
10475 		if (r) {
10476 			vcpu->arch.smi_pending = false;
10477 			++vcpu->arch.smi_count;
10478 			enter_smm(vcpu);
10479 			can_inject = false;
10480 		} else
10481 			static_call(kvm_x86_enable_smi_window)(vcpu);
10482 	}
10483 #endif
10484 
10485 	if (vcpu->arch.nmi_pending) {
10486 		r = can_inject ? static_call(kvm_x86_nmi_allowed)(vcpu, true) : -EBUSY;
10487 		if (r < 0)
10488 			goto out;
10489 		if (r) {
10490 			--vcpu->arch.nmi_pending;
10491 			vcpu->arch.nmi_injected = true;
10492 			static_call(kvm_x86_inject_nmi)(vcpu);
10493 			can_inject = false;
10494 			WARN_ON(static_call(kvm_x86_nmi_allowed)(vcpu, true) < 0);
10495 		}
10496 		if (vcpu->arch.nmi_pending)
10497 			static_call(kvm_x86_enable_nmi_window)(vcpu);
10498 	}
10499 
10500 	if (kvm_cpu_has_injectable_intr(vcpu)) {
10501 		r = can_inject ? static_call(kvm_x86_interrupt_allowed)(vcpu, true) : -EBUSY;
10502 		if (r < 0)
10503 			goto out;
10504 		if (r) {
10505 			int irq = kvm_cpu_get_interrupt(vcpu);
10506 
10507 			if (!WARN_ON_ONCE(irq == -1)) {
10508 				kvm_queue_interrupt(vcpu, irq, false);
10509 				static_call(kvm_x86_inject_irq)(vcpu, false);
10510 				WARN_ON(static_call(kvm_x86_interrupt_allowed)(vcpu, true) < 0);
10511 			}
10512 		}
10513 		if (kvm_cpu_has_injectable_intr(vcpu))
10514 			static_call(kvm_x86_enable_irq_window)(vcpu);
10515 	}
10516 
10517 	if (is_guest_mode(vcpu) &&
10518 	    kvm_x86_ops.nested_ops->has_events &&
10519 	    kvm_x86_ops.nested_ops->has_events(vcpu))
10520 		*req_immediate_exit = true;
10521 
10522 	/*
10523 	 * KVM must never queue a new exception while injecting an event; KVM
10524 	 * is done emulating and should only propagate the to-be-injected event
10525 	 * to the VMCS/VMCB.  Queueing a new exception can put the vCPU into an
10526 	 * infinite loop as KVM will bail from VM-Enter to inject the pending
10527 	 * exception and start the cycle all over.
10528 	 *
10529 	 * Exempt triple faults as they have special handling and won't put the
10530 	 * vCPU into an infinite loop.  Triple fault can be queued when running
10531 	 * VMX without unrestricted guest, as that requires KVM to emulate Real
10532 	 * Mode events (see kvm_inject_realmode_interrupt()).
10533 	 */
10534 	WARN_ON_ONCE(vcpu->arch.exception.pending ||
10535 		     vcpu->arch.exception_vmexit.pending);
10536 	return 0;
10537 
10538 out:
10539 	if (r == -EBUSY) {
10540 		*req_immediate_exit = true;
10541 		r = 0;
10542 	}
10543 	return r;
10544 }
10545 
process_nmi(struct kvm_vcpu * vcpu)10546 static void process_nmi(struct kvm_vcpu *vcpu)
10547 {
10548 	unsigned int limit;
10549 
10550 	/*
10551 	 * x86 is limited to one NMI pending, but because KVM can't react to
10552 	 * incoming NMIs as quickly as bare metal, e.g. if the vCPU is
10553 	 * scheduled out, KVM needs to play nice with two queued NMIs showing
10554 	 * up at the same time.  To handle this scenario, allow two NMIs to be
10555 	 * (temporarily) pending so long as NMIs are not blocked and KVM is not
10556 	 * waiting for a previous NMI injection to complete (which effectively
10557 	 * blocks NMIs).  KVM will immediately inject one of the two NMIs, and
10558 	 * will request an NMI window to handle the second NMI.
10559 	 */
10560 	if (static_call(kvm_x86_get_nmi_mask)(vcpu) || vcpu->arch.nmi_injected)
10561 		limit = 1;
10562 	else
10563 		limit = 2;
10564 
10565 	/*
10566 	 * Adjust the limit to account for pending virtual NMIs, which aren't
10567 	 * tracked in vcpu->arch.nmi_pending.
10568 	 */
10569 	if (static_call(kvm_x86_is_vnmi_pending)(vcpu))
10570 		limit--;
10571 
10572 	vcpu->arch.nmi_pending += atomic_xchg(&vcpu->arch.nmi_queued, 0);
10573 	vcpu->arch.nmi_pending = min(vcpu->arch.nmi_pending, limit);
10574 
10575 	if (vcpu->arch.nmi_pending &&
10576 	    (static_call(kvm_x86_set_vnmi_pending)(vcpu)))
10577 		vcpu->arch.nmi_pending--;
10578 
10579 	if (vcpu->arch.nmi_pending)
10580 		kvm_make_request(KVM_REQ_EVENT, vcpu);
10581 }
10582 
10583 /* Return total number of NMIs pending injection to the VM */
kvm_get_nr_pending_nmis(struct kvm_vcpu * vcpu)10584 int kvm_get_nr_pending_nmis(struct kvm_vcpu *vcpu)
10585 {
10586 	return vcpu->arch.nmi_pending +
10587 	       static_call(kvm_x86_is_vnmi_pending)(vcpu);
10588 }
10589 
kvm_make_scan_ioapic_request_mask(struct kvm * kvm,unsigned long * vcpu_bitmap)10590 void kvm_make_scan_ioapic_request_mask(struct kvm *kvm,
10591 				       unsigned long *vcpu_bitmap)
10592 {
10593 	kvm_make_vcpus_request_mask(kvm, KVM_REQ_SCAN_IOAPIC, vcpu_bitmap);
10594 }
10595 
kvm_make_scan_ioapic_request(struct kvm * kvm)10596 void kvm_make_scan_ioapic_request(struct kvm *kvm)
10597 {
10598 	kvm_make_all_cpus_request(kvm, KVM_REQ_SCAN_IOAPIC);
10599 }
10600 
__kvm_vcpu_update_apicv(struct kvm_vcpu * vcpu)10601 void __kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu)
10602 {
10603 	struct kvm_lapic *apic = vcpu->arch.apic;
10604 	bool activate;
10605 
10606 	if (!lapic_in_kernel(vcpu))
10607 		return;
10608 
10609 	down_read(&vcpu->kvm->arch.apicv_update_lock);
10610 	preempt_disable();
10611 
10612 	/* Do not activate APICV when APIC is disabled */
10613 	activate = kvm_vcpu_apicv_activated(vcpu) &&
10614 		   (kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED);
10615 
10616 	if (apic->apicv_active == activate)
10617 		goto out;
10618 
10619 	apic->apicv_active = activate;
10620 	kvm_apic_update_apicv(vcpu);
10621 	static_call(kvm_x86_refresh_apicv_exec_ctrl)(vcpu);
10622 
10623 	/*
10624 	 * When APICv gets disabled, we may still have injected interrupts
10625 	 * pending. At the same time, KVM_REQ_EVENT may not be set as APICv was
10626 	 * still active when the interrupt got accepted. Make sure
10627 	 * kvm_check_and_inject_events() is called to check for that.
10628 	 */
10629 	if (!apic->apicv_active)
10630 		kvm_make_request(KVM_REQ_EVENT, vcpu);
10631 
10632 out:
10633 	preempt_enable();
10634 	up_read(&vcpu->kvm->arch.apicv_update_lock);
10635 }
10636 EXPORT_SYMBOL_GPL(__kvm_vcpu_update_apicv);
10637 
kvm_vcpu_update_apicv(struct kvm_vcpu * vcpu)10638 static void kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu)
10639 {
10640 	if (!lapic_in_kernel(vcpu))
10641 		return;
10642 
10643 	/*
10644 	 * Due to sharing page tables across vCPUs, the xAPIC memslot must be
10645 	 * deleted if any vCPU has xAPIC virtualization and x2APIC enabled, but
10646 	 * and hardware doesn't support x2APIC virtualization.  E.g. some AMD
10647 	 * CPUs support AVIC but not x2APIC.  KVM still allows enabling AVIC in
10648 	 * this case so that KVM can the AVIC doorbell to inject interrupts to
10649 	 * running vCPUs, but KVM must not create SPTEs for the APIC base as
10650 	 * the vCPU would incorrectly be able to access the vAPIC page via MMIO
10651 	 * despite being in x2APIC mode.  For simplicity, inhibiting the APIC
10652 	 * access page is sticky.
10653 	 */
10654 	if (apic_x2apic_mode(vcpu->arch.apic) &&
10655 	    kvm_x86_ops.allow_apicv_in_x2apic_without_x2apic_virtualization)
10656 		kvm_inhibit_apic_access_page(vcpu);
10657 
10658 	__kvm_vcpu_update_apicv(vcpu);
10659 }
10660 
__kvm_set_or_clear_apicv_inhibit(struct kvm * kvm,enum kvm_apicv_inhibit reason,bool set)10661 void __kvm_set_or_clear_apicv_inhibit(struct kvm *kvm,
10662 				      enum kvm_apicv_inhibit reason, bool set)
10663 {
10664 	unsigned long old, new;
10665 
10666 	lockdep_assert_held_write(&kvm->arch.apicv_update_lock);
10667 
10668 	if (!(kvm_x86_ops.required_apicv_inhibits & BIT(reason)))
10669 		return;
10670 
10671 	old = new = kvm->arch.apicv_inhibit_reasons;
10672 
10673 	set_or_clear_apicv_inhibit(&new, reason, set);
10674 
10675 	if (!!old != !!new) {
10676 		/*
10677 		 * Kick all vCPUs before setting apicv_inhibit_reasons to avoid
10678 		 * false positives in the sanity check WARN in svm_vcpu_run().
10679 		 * This task will wait for all vCPUs to ack the kick IRQ before
10680 		 * updating apicv_inhibit_reasons, and all other vCPUs will
10681 		 * block on acquiring apicv_update_lock so that vCPUs can't
10682 		 * redo svm_vcpu_run() without seeing the new inhibit state.
10683 		 *
10684 		 * Note, holding apicv_update_lock and taking it in the read
10685 		 * side (handling the request) also prevents other vCPUs from
10686 		 * servicing the request with a stale apicv_inhibit_reasons.
10687 		 */
10688 		kvm_make_all_cpus_request(kvm, KVM_REQ_APICV_UPDATE);
10689 		kvm->arch.apicv_inhibit_reasons = new;
10690 		if (new) {
10691 			unsigned long gfn = gpa_to_gfn(APIC_DEFAULT_PHYS_BASE);
10692 			int idx = srcu_read_lock(&kvm->srcu);
10693 
10694 			kvm_zap_gfn_range(kvm, gfn, gfn+1);
10695 			srcu_read_unlock(&kvm->srcu, idx);
10696 		}
10697 	} else {
10698 		kvm->arch.apicv_inhibit_reasons = new;
10699 	}
10700 }
10701 
kvm_set_or_clear_apicv_inhibit(struct kvm * kvm,enum kvm_apicv_inhibit reason,bool set)10702 void kvm_set_or_clear_apicv_inhibit(struct kvm *kvm,
10703 				    enum kvm_apicv_inhibit reason, bool set)
10704 {
10705 	if (!enable_apicv)
10706 		return;
10707 
10708 	down_write(&kvm->arch.apicv_update_lock);
10709 	__kvm_set_or_clear_apicv_inhibit(kvm, reason, set);
10710 	up_write(&kvm->arch.apicv_update_lock);
10711 }
10712 EXPORT_SYMBOL_GPL(kvm_set_or_clear_apicv_inhibit);
10713 
vcpu_scan_ioapic(struct kvm_vcpu * vcpu)10714 static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu)
10715 {
10716 	if (!kvm_apic_present(vcpu))
10717 		return;
10718 
10719 	bitmap_zero(vcpu->arch.ioapic_handled_vectors, 256);
10720 
10721 	if (irqchip_split(vcpu->kvm))
10722 		kvm_scan_ioapic_routes(vcpu, vcpu->arch.ioapic_handled_vectors);
10723 	else {
10724 		static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu);
10725 		if (ioapic_in_kernel(vcpu->kvm))
10726 			kvm_ioapic_scan_entry(vcpu, vcpu->arch.ioapic_handled_vectors);
10727 	}
10728 
10729 	if (is_guest_mode(vcpu))
10730 		vcpu->arch.load_eoi_exitmap_pending = true;
10731 	else
10732 		kvm_make_request(KVM_REQ_LOAD_EOI_EXITMAP, vcpu);
10733 }
10734 
vcpu_load_eoi_exitmap(struct kvm_vcpu * vcpu)10735 static void vcpu_load_eoi_exitmap(struct kvm_vcpu *vcpu)
10736 {
10737 	if (!kvm_apic_hw_enabled(vcpu->arch.apic))
10738 		return;
10739 
10740 #ifdef CONFIG_KVM_HYPERV
10741 	if (to_hv_vcpu(vcpu)) {
10742 		u64 eoi_exit_bitmap[4];
10743 
10744 		bitmap_or((ulong *)eoi_exit_bitmap,
10745 			  vcpu->arch.ioapic_handled_vectors,
10746 			  to_hv_synic(vcpu)->vec_bitmap, 256);
10747 		static_call_cond(kvm_x86_load_eoi_exitmap)(vcpu, eoi_exit_bitmap);
10748 		return;
10749 	}
10750 #endif
10751 	static_call_cond(kvm_x86_load_eoi_exitmap)(
10752 		vcpu, (u64 *)vcpu->arch.ioapic_handled_vectors);
10753 }
10754 
kvm_arch_guest_memory_reclaimed(struct kvm * kvm)10755 void kvm_arch_guest_memory_reclaimed(struct kvm *kvm)
10756 {
10757 	static_call_cond(kvm_x86_guest_memory_reclaimed)(kvm);
10758 }
10759 
kvm_vcpu_reload_apic_access_page(struct kvm_vcpu * vcpu)10760 static void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu)
10761 {
10762 	if (!lapic_in_kernel(vcpu))
10763 		return;
10764 
10765 	static_call_cond(kvm_x86_set_apic_access_page_addr)(vcpu);
10766 }
10767 
10768 /*
10769  * Called within kvm->srcu read side.
10770  * Returns 1 to let vcpu_run() continue the guest execution loop without
10771  * exiting to the userspace.  Otherwise, the value will be returned to the
10772  * userspace.
10773  */
vcpu_enter_guest(struct kvm_vcpu * vcpu)10774 static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
10775 {
10776 	int r;
10777 	bool req_int_win =
10778 		dm_request_for_irq_injection(vcpu) &&
10779 		kvm_cpu_accept_dm_intr(vcpu);
10780 	fastpath_t exit_fastpath;
10781 
10782 	bool req_immediate_exit = false;
10783 
10784 	if (kvm_request_pending(vcpu)) {
10785 		if (kvm_check_request(KVM_REQ_VM_DEAD, vcpu)) {
10786 			r = -EIO;
10787 			goto out;
10788 		}
10789 
10790 		if (kvm_dirty_ring_check_request(vcpu)) {
10791 			r = 0;
10792 			goto out;
10793 		}
10794 
10795 		if (kvm_check_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu)) {
10796 			if (unlikely(!kvm_x86_ops.nested_ops->get_nested_state_pages(vcpu))) {
10797 				r = 0;
10798 				goto out;
10799 			}
10800 		}
10801 		if (kvm_check_request(KVM_REQ_MMU_FREE_OBSOLETE_ROOTS, vcpu))
10802 			kvm_mmu_free_obsolete_roots(vcpu);
10803 		if (kvm_check_request(KVM_REQ_MIGRATE_TIMER, vcpu))
10804 			__kvm_migrate_timers(vcpu);
10805 		if (kvm_check_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu))
10806 			kvm_update_masterclock(vcpu->kvm);
10807 		if (kvm_check_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu))
10808 			kvm_gen_kvmclock_update(vcpu);
10809 		if (kvm_check_request(KVM_REQ_CLOCK_UPDATE, vcpu)) {
10810 			r = kvm_guest_time_update(vcpu);
10811 			if (unlikely(r))
10812 				goto out;
10813 		}
10814 		if (kvm_check_request(KVM_REQ_MMU_SYNC, vcpu))
10815 			kvm_mmu_sync_roots(vcpu);
10816 		if (kvm_check_request(KVM_REQ_LOAD_MMU_PGD, vcpu))
10817 			kvm_mmu_load_pgd(vcpu);
10818 
10819 		/*
10820 		 * Note, the order matters here, as flushing "all" TLB entries
10821 		 * also flushes the "current" TLB entries, i.e. servicing the
10822 		 * flush "all" will clear any request to flush "current".
10823 		 */
10824 		if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu))
10825 			kvm_vcpu_flush_tlb_all(vcpu);
10826 
10827 		kvm_service_local_tlb_flush_requests(vcpu);
10828 
10829 		/*
10830 		 * Fall back to a "full" guest flush if Hyper-V's precise
10831 		 * flushing fails.  Note, Hyper-V's flushing is per-vCPU, but
10832 		 * the flushes are considered "remote" and not "local" because
10833 		 * the requests can be initiated from other vCPUs.
10834 		 */
10835 #ifdef CONFIG_KVM_HYPERV
10836 		if (kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu) &&
10837 		    kvm_hv_vcpu_flush_tlb(vcpu))
10838 			kvm_vcpu_flush_tlb_guest(vcpu);
10839 #endif
10840 
10841 		if (kvm_check_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu)) {
10842 			vcpu->run->exit_reason = KVM_EXIT_TPR_ACCESS;
10843 			r = 0;
10844 			goto out;
10845 		}
10846 		if (kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu)) {
10847 			if (is_guest_mode(vcpu))
10848 				kvm_x86_ops.nested_ops->triple_fault(vcpu);
10849 
10850 			if (kvm_check_request(KVM_REQ_TRIPLE_FAULT, vcpu)) {
10851 				vcpu->run->exit_reason = KVM_EXIT_SHUTDOWN;
10852 				vcpu->mmio_needed = 0;
10853 				r = 0;
10854 				goto out;
10855 			}
10856 		}
10857 		if (kvm_check_request(KVM_REQ_APF_HALT, vcpu)) {
10858 			/* Page is swapped out. Do synthetic halt */
10859 			vcpu->arch.apf.halted = true;
10860 			r = 1;
10861 			goto out;
10862 		}
10863 		if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu))
10864 			record_steal_time(vcpu);
10865 		if (kvm_check_request(KVM_REQ_PMU, vcpu))
10866 			kvm_pmu_handle_event(vcpu);
10867 		if (kvm_check_request(KVM_REQ_PMI, vcpu))
10868 			kvm_pmu_deliver_pmi(vcpu);
10869 #ifdef CONFIG_KVM_SMM
10870 		if (kvm_check_request(KVM_REQ_SMI, vcpu))
10871 			process_smi(vcpu);
10872 #endif
10873 		if (kvm_check_request(KVM_REQ_NMI, vcpu))
10874 			process_nmi(vcpu);
10875 		if (kvm_check_request(KVM_REQ_IOAPIC_EOI_EXIT, vcpu)) {
10876 			BUG_ON(vcpu->arch.pending_ioapic_eoi > 255);
10877 			if (test_bit(vcpu->arch.pending_ioapic_eoi,
10878 				     vcpu->arch.ioapic_handled_vectors)) {
10879 				vcpu->run->exit_reason = KVM_EXIT_IOAPIC_EOI;
10880 				vcpu->run->eoi.vector =
10881 						vcpu->arch.pending_ioapic_eoi;
10882 				r = 0;
10883 				goto out;
10884 			}
10885 		}
10886 		if (kvm_check_request(KVM_REQ_SCAN_IOAPIC, vcpu))
10887 			vcpu_scan_ioapic(vcpu);
10888 		if (kvm_check_request(KVM_REQ_LOAD_EOI_EXITMAP, vcpu))
10889 			vcpu_load_eoi_exitmap(vcpu);
10890 		if (kvm_check_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu))
10891 			kvm_vcpu_reload_apic_access_page(vcpu);
10892 #ifdef CONFIG_KVM_HYPERV
10893 		if (kvm_check_request(KVM_REQ_HV_CRASH, vcpu)) {
10894 			vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
10895 			vcpu->run->system_event.type = KVM_SYSTEM_EVENT_CRASH;
10896 			vcpu->run->system_event.ndata = 0;
10897 			r = 0;
10898 			goto out;
10899 		}
10900 		if (kvm_check_request(KVM_REQ_HV_RESET, vcpu)) {
10901 			vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
10902 			vcpu->run->system_event.type = KVM_SYSTEM_EVENT_RESET;
10903 			vcpu->run->system_event.ndata = 0;
10904 			r = 0;
10905 			goto out;
10906 		}
10907 		if (kvm_check_request(KVM_REQ_HV_EXIT, vcpu)) {
10908 			struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
10909 
10910 			vcpu->run->exit_reason = KVM_EXIT_HYPERV;
10911 			vcpu->run->hyperv = hv_vcpu->exit;
10912 			r = 0;
10913 			goto out;
10914 		}
10915 
10916 		/*
10917 		 * KVM_REQ_HV_STIMER has to be processed after
10918 		 * KVM_REQ_CLOCK_UPDATE, because Hyper-V SynIC timers
10919 		 * depend on the guest clock being up-to-date
10920 		 */
10921 		if (kvm_check_request(KVM_REQ_HV_STIMER, vcpu))
10922 			kvm_hv_process_stimers(vcpu);
10923 #endif
10924 		if (kvm_check_request(KVM_REQ_APICV_UPDATE, vcpu))
10925 			kvm_vcpu_update_apicv(vcpu);
10926 		if (kvm_check_request(KVM_REQ_APF_READY, vcpu))
10927 			kvm_check_async_pf_completion(vcpu);
10928 		if (kvm_check_request(KVM_REQ_MSR_FILTER_CHANGED, vcpu))
10929 			static_call(kvm_x86_msr_filter_changed)(vcpu);
10930 
10931 		if (kvm_check_request(KVM_REQ_UPDATE_CPU_DIRTY_LOGGING, vcpu))
10932 			static_call(kvm_x86_update_cpu_dirty_logging)(vcpu);
10933 	}
10934 
10935 	if (kvm_check_request(KVM_REQ_EVENT, vcpu) || req_int_win ||
10936 	    kvm_xen_has_interrupt(vcpu)) {
10937 		++vcpu->stat.req_event;
10938 		r = kvm_apic_accept_events(vcpu);
10939 		if (r < 0) {
10940 			r = 0;
10941 			goto out;
10942 		}
10943 		if (vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) {
10944 			r = 1;
10945 			goto out;
10946 		}
10947 
10948 		r = kvm_check_and_inject_events(vcpu, &req_immediate_exit);
10949 		if (r < 0) {
10950 			r = 0;
10951 			goto out;
10952 		}
10953 		if (req_int_win)
10954 			static_call(kvm_x86_enable_irq_window)(vcpu);
10955 
10956 		if (kvm_lapic_enabled(vcpu)) {
10957 			update_cr8_intercept(vcpu);
10958 			kvm_lapic_sync_to_vapic(vcpu);
10959 		}
10960 	}
10961 
10962 	r = kvm_mmu_reload(vcpu);
10963 	if (unlikely(r)) {
10964 		goto cancel_injection;
10965 	}
10966 
10967 	preempt_disable();
10968 
10969 	static_call(kvm_x86_prepare_switch_to_guest)(vcpu);
10970 
10971 	/*
10972 	 * Disable IRQs before setting IN_GUEST_MODE.  Posted interrupt
10973 	 * IPI are then delayed after guest entry, which ensures that they
10974 	 * result in virtual interrupt delivery.
10975 	 */
10976 	local_irq_disable();
10977 
10978 	/* Store vcpu->apicv_active before vcpu->mode.  */
10979 	smp_store_release(&vcpu->mode, IN_GUEST_MODE);
10980 
10981 	kvm_vcpu_srcu_read_unlock(vcpu);
10982 
10983 	/*
10984 	 * 1) We should set ->mode before checking ->requests.  Please see
10985 	 * the comment in kvm_vcpu_exiting_guest_mode().
10986 	 *
10987 	 * 2) For APICv, we should set ->mode before checking PID.ON. This
10988 	 * pairs with the memory barrier implicit in pi_test_and_set_on
10989 	 * (see vmx_deliver_posted_interrupt).
10990 	 *
10991 	 * 3) This also orders the write to mode from any reads to the page
10992 	 * tables done while the VCPU is running.  Please see the comment
10993 	 * in kvm_flush_remote_tlbs.
10994 	 */
10995 	smp_mb__after_srcu_read_unlock();
10996 
10997 	/*
10998 	 * Process pending posted interrupts to handle the case where the
10999 	 * notification IRQ arrived in the host, or was never sent (because the
11000 	 * target vCPU wasn't running).  Do this regardless of the vCPU's APICv
11001 	 * status, KVM doesn't update assigned devices when APICv is inhibited,
11002 	 * i.e. they can post interrupts even if APICv is temporarily disabled.
11003 	 */
11004 	if (kvm_lapic_enabled(vcpu))
11005 		static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu);
11006 
11007 	if (kvm_vcpu_exit_request(vcpu)) {
11008 		vcpu->mode = OUTSIDE_GUEST_MODE;
11009 		smp_wmb();
11010 		local_irq_enable();
11011 		preempt_enable();
11012 		kvm_vcpu_srcu_read_lock(vcpu);
11013 		r = 1;
11014 		goto cancel_injection;
11015 	}
11016 
11017 	if (req_immediate_exit)
11018 		kvm_make_request(KVM_REQ_EVENT, vcpu);
11019 
11020 	fpregs_assert_state_consistent();
11021 	if (test_thread_flag(TIF_NEED_FPU_LOAD))
11022 		switch_fpu_return();
11023 
11024 	if (vcpu->arch.guest_fpu.xfd_err)
11025 		wrmsrl(MSR_IA32_XFD_ERR, vcpu->arch.guest_fpu.xfd_err);
11026 
11027 	if (unlikely(vcpu->arch.switch_db_regs)) {
11028 		set_debugreg(0, 7);
11029 		set_debugreg(vcpu->arch.eff_db[0], 0);
11030 		set_debugreg(vcpu->arch.eff_db[1], 1);
11031 		set_debugreg(vcpu->arch.eff_db[2], 2);
11032 		set_debugreg(vcpu->arch.eff_db[3], 3);
11033 	} else if (unlikely(hw_breakpoint_active())) {
11034 		set_debugreg(0, 7);
11035 	}
11036 
11037 	guest_timing_enter_irqoff();
11038 
11039 	for (;;) {
11040 		/*
11041 		 * Assert that vCPU vs. VM APICv state is consistent.  An APICv
11042 		 * update must kick and wait for all vCPUs before toggling the
11043 		 * per-VM state, and responding vCPUs must wait for the update
11044 		 * to complete before servicing KVM_REQ_APICV_UPDATE.
11045 		 */
11046 		WARN_ON_ONCE((kvm_vcpu_apicv_activated(vcpu) != kvm_vcpu_apicv_active(vcpu)) &&
11047 			     (kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED));
11048 
11049 		exit_fastpath = static_call(kvm_x86_vcpu_run)(vcpu, req_immediate_exit);
11050 		if (likely(exit_fastpath != EXIT_FASTPATH_REENTER_GUEST))
11051 			break;
11052 
11053 		if (kvm_lapic_enabled(vcpu))
11054 			static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu);
11055 
11056 		if (unlikely(kvm_vcpu_exit_request(vcpu))) {
11057 			exit_fastpath = EXIT_FASTPATH_EXIT_HANDLED;
11058 			break;
11059 		}
11060 
11061 		/* Note, VM-Exits that go down the "slow" path are accounted below. */
11062 		++vcpu->stat.exits;
11063 	}
11064 
11065 	/*
11066 	 * Do this here before restoring debug registers on the host.  And
11067 	 * since we do this before handling the vmexit, a DR access vmexit
11068 	 * can (a) read the correct value of the debug registers, (b) set
11069 	 * KVM_DEBUGREG_WONT_EXIT again.
11070 	 */
11071 	if (unlikely(vcpu->arch.switch_db_regs & KVM_DEBUGREG_WONT_EXIT)) {
11072 		WARN_ON(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP);
11073 		static_call(kvm_x86_sync_dirty_debug_regs)(vcpu);
11074 		kvm_update_dr0123(vcpu);
11075 		kvm_update_dr7(vcpu);
11076 	}
11077 
11078 	/*
11079 	 * If the guest has used debug registers, at least dr7
11080 	 * will be disabled while returning to the host.
11081 	 * If we don't have active breakpoints in the host, we don't
11082 	 * care about the messed up debug address registers. But if
11083 	 * we have some of them active, restore the old state.
11084 	 */
11085 	if (hw_breakpoint_active())
11086 		hw_breakpoint_restore();
11087 
11088 	vcpu->arch.last_vmentry_cpu = vcpu->cpu;
11089 	vcpu->arch.last_guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
11090 
11091 	vcpu->mode = OUTSIDE_GUEST_MODE;
11092 	smp_wmb();
11093 
11094 	/*
11095 	 * Sync xfd before calling handle_exit_irqoff() which may
11096 	 * rely on the fact that guest_fpu::xfd is up-to-date (e.g.
11097 	 * in #NM irqoff handler).
11098 	 */
11099 	if (vcpu->arch.xfd_no_write_intercept)
11100 		fpu_sync_guest_vmexit_xfd_state();
11101 
11102 	static_call(kvm_x86_handle_exit_irqoff)(vcpu);
11103 
11104 	if (vcpu->arch.guest_fpu.xfd_err)
11105 		wrmsrl(MSR_IA32_XFD_ERR, 0);
11106 
11107 	/*
11108 	 * Consume any pending interrupts, including the possible source of
11109 	 * VM-Exit on SVM and any ticks that occur between VM-Exit and now.
11110 	 * An instruction is required after local_irq_enable() to fully unblock
11111 	 * interrupts on processors that implement an interrupt shadow, the
11112 	 * stat.exits increment will do nicely.
11113 	 */
11114 	kvm_before_interrupt(vcpu, KVM_HANDLING_IRQ);
11115 	local_irq_enable();
11116 	++vcpu->stat.exits;
11117 	local_irq_disable();
11118 	kvm_after_interrupt(vcpu);
11119 
11120 	/*
11121 	 * Wait until after servicing IRQs to account guest time so that any
11122 	 * ticks that occurred while running the guest are properly accounted
11123 	 * to the guest.  Waiting until IRQs are enabled degrades the accuracy
11124 	 * of accounting via context tracking, but the loss of accuracy is
11125 	 * acceptable for all known use cases.
11126 	 */
11127 	guest_timing_exit_irqoff();
11128 
11129 	local_irq_enable();
11130 	preempt_enable();
11131 
11132 	kvm_vcpu_srcu_read_lock(vcpu);
11133 
11134 	/*
11135 	 * Profile KVM exit RIPs:
11136 	 */
11137 	if (unlikely(prof_on == KVM_PROFILING)) {
11138 		unsigned long rip = kvm_rip_read(vcpu);
11139 		profile_hit(KVM_PROFILING, (void *)rip);
11140 	}
11141 
11142 	if (unlikely(vcpu->arch.tsc_always_catchup))
11143 		kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
11144 
11145 	if (vcpu->arch.apic_attention)
11146 		kvm_lapic_sync_from_vapic(vcpu);
11147 
11148 	r = static_call(kvm_x86_handle_exit)(vcpu, exit_fastpath);
11149 	return r;
11150 
11151 cancel_injection:
11152 	if (req_immediate_exit)
11153 		kvm_make_request(KVM_REQ_EVENT, vcpu);
11154 	static_call(kvm_x86_cancel_injection)(vcpu);
11155 	if (unlikely(vcpu->arch.apic_attention))
11156 		kvm_lapic_sync_from_vapic(vcpu);
11157 out:
11158 	return r;
11159 }
11160 
11161 /* Called within kvm->srcu read side.  */
vcpu_block(struct kvm_vcpu * vcpu)11162 static inline int vcpu_block(struct kvm_vcpu *vcpu)
11163 {
11164 	bool hv_timer;
11165 
11166 	if (!kvm_arch_vcpu_runnable(vcpu)) {
11167 		/*
11168 		 * Switch to the software timer before halt-polling/blocking as
11169 		 * the guest's timer may be a break event for the vCPU, and the
11170 		 * hypervisor timer runs only when the CPU is in guest mode.
11171 		 * Switch before halt-polling so that KVM recognizes an expired
11172 		 * timer before blocking.
11173 		 */
11174 		hv_timer = kvm_lapic_hv_timer_in_use(vcpu);
11175 		if (hv_timer)
11176 			kvm_lapic_switch_to_sw_timer(vcpu);
11177 
11178 		kvm_vcpu_srcu_read_unlock(vcpu);
11179 		if (vcpu->arch.mp_state == KVM_MP_STATE_HALTED)
11180 			kvm_vcpu_halt(vcpu);
11181 		else
11182 			kvm_vcpu_block(vcpu);
11183 		kvm_vcpu_srcu_read_lock(vcpu);
11184 
11185 		if (hv_timer)
11186 			kvm_lapic_switch_to_hv_timer(vcpu);
11187 
11188 		/*
11189 		 * If the vCPU is not runnable, a signal or another host event
11190 		 * of some kind is pending; service it without changing the
11191 		 * vCPU's activity state.
11192 		 */
11193 		if (!kvm_arch_vcpu_runnable(vcpu))
11194 			return 1;
11195 	}
11196 
11197 	/*
11198 	 * Evaluate nested events before exiting the halted state.  This allows
11199 	 * the halt state to be recorded properly in the VMCS12's activity
11200 	 * state field (AMD does not have a similar field and a VM-Exit always
11201 	 * causes a spurious wakeup from HLT).
11202 	 */
11203 	if (is_guest_mode(vcpu)) {
11204 		if (kvm_check_nested_events(vcpu) < 0)
11205 			return 0;
11206 	}
11207 
11208 	if (kvm_apic_accept_events(vcpu) < 0)
11209 		return 0;
11210 	switch(vcpu->arch.mp_state) {
11211 	case KVM_MP_STATE_HALTED:
11212 	case KVM_MP_STATE_AP_RESET_HOLD:
11213 		vcpu->arch.pv.pv_unhalted = false;
11214 		vcpu->arch.mp_state =
11215 			KVM_MP_STATE_RUNNABLE;
11216 		fallthrough;
11217 	case KVM_MP_STATE_RUNNABLE:
11218 		vcpu->arch.apf.halted = false;
11219 		break;
11220 	case KVM_MP_STATE_INIT_RECEIVED:
11221 		break;
11222 	default:
11223 		WARN_ON_ONCE(1);
11224 		break;
11225 	}
11226 	return 1;
11227 }
11228 
kvm_vcpu_running(struct kvm_vcpu * vcpu)11229 static inline bool kvm_vcpu_running(struct kvm_vcpu *vcpu)
11230 {
11231 	return (vcpu->arch.mp_state == KVM_MP_STATE_RUNNABLE &&
11232 		!vcpu->arch.apf.halted);
11233 }
11234 
11235 /* Called within kvm->srcu read side.  */
vcpu_run(struct kvm_vcpu * vcpu)11236 static int vcpu_run(struct kvm_vcpu *vcpu)
11237 {
11238 	int r;
11239 
11240 	vcpu->run->exit_reason = KVM_EXIT_UNKNOWN;
11241 	vcpu->arch.l1tf_flush_l1d = true;
11242 
11243 	for (;;) {
11244 		/*
11245 		 * If another guest vCPU requests a PV TLB flush in the middle
11246 		 * of instruction emulation, the rest of the emulation could
11247 		 * use a stale page translation. Assume that any code after
11248 		 * this point can start executing an instruction.
11249 		 */
11250 		vcpu->arch.at_instruction_boundary = false;
11251 		if (kvm_vcpu_running(vcpu)) {
11252 			r = vcpu_enter_guest(vcpu);
11253 		} else {
11254 			r = vcpu_block(vcpu);
11255 		}
11256 
11257 		if (r <= 0)
11258 			break;
11259 
11260 		kvm_clear_request(KVM_REQ_UNBLOCK, vcpu);
11261 		if (kvm_xen_has_pending_events(vcpu))
11262 			kvm_xen_inject_pending_events(vcpu);
11263 
11264 		if (kvm_cpu_has_pending_timer(vcpu))
11265 			kvm_inject_pending_timer_irqs(vcpu);
11266 
11267 		if (dm_request_for_irq_injection(vcpu) &&
11268 			kvm_vcpu_ready_for_interrupt_injection(vcpu)) {
11269 			r = 0;
11270 			vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
11271 			++vcpu->stat.request_irq_exits;
11272 			break;
11273 		}
11274 
11275 		if (__xfer_to_guest_mode_work_pending()) {
11276 			kvm_vcpu_srcu_read_unlock(vcpu);
11277 			r = xfer_to_guest_mode_handle_work(vcpu);
11278 			kvm_vcpu_srcu_read_lock(vcpu);
11279 			if (r)
11280 				return r;
11281 		}
11282 	}
11283 
11284 	return r;
11285 }
11286 
complete_emulated_io(struct kvm_vcpu * vcpu)11287 static inline int complete_emulated_io(struct kvm_vcpu *vcpu)
11288 {
11289 	return kvm_emulate_instruction(vcpu, EMULTYPE_NO_DECODE);
11290 }
11291 
complete_emulated_pio(struct kvm_vcpu * vcpu)11292 static int complete_emulated_pio(struct kvm_vcpu *vcpu)
11293 {
11294 	BUG_ON(!vcpu->arch.pio.count);
11295 
11296 	return complete_emulated_io(vcpu);
11297 }
11298 
11299 /*
11300  * Implements the following, as a state machine:
11301  *
11302  * read:
11303  *   for each fragment
11304  *     for each mmio piece in the fragment
11305  *       write gpa, len
11306  *       exit
11307  *       copy data
11308  *   execute insn
11309  *
11310  * write:
11311  *   for each fragment
11312  *     for each mmio piece in the fragment
11313  *       write gpa, len
11314  *       copy data
11315  *       exit
11316  */
complete_emulated_mmio(struct kvm_vcpu * vcpu)11317 static int complete_emulated_mmio(struct kvm_vcpu *vcpu)
11318 {
11319 	struct kvm_run *run = vcpu->run;
11320 	struct kvm_mmio_fragment *frag;
11321 	unsigned len;
11322 
11323 	BUG_ON(!vcpu->mmio_needed);
11324 
11325 	/* Complete previous fragment */
11326 	frag = &vcpu->mmio_fragments[vcpu->mmio_cur_fragment];
11327 	len = min(8u, frag->len);
11328 	if (!vcpu->mmio_is_write)
11329 		memcpy(frag->data, run->mmio.data, len);
11330 
11331 	if (frag->len <= 8) {
11332 		/* Switch to the next fragment. */
11333 		frag++;
11334 		vcpu->mmio_cur_fragment++;
11335 	} else {
11336 		/* Go forward to the next mmio piece. */
11337 		frag->data += len;
11338 		frag->gpa += len;
11339 		frag->len -= len;
11340 	}
11341 
11342 	if (vcpu->mmio_cur_fragment >= vcpu->mmio_nr_fragments) {
11343 		vcpu->mmio_needed = 0;
11344 
11345 		/* FIXME: return into emulator if single-stepping.  */
11346 		if (vcpu->mmio_is_write)
11347 			return 1;
11348 		vcpu->mmio_read_completed = 1;
11349 		return complete_emulated_io(vcpu);
11350 	}
11351 
11352 	run->exit_reason = KVM_EXIT_MMIO;
11353 	run->mmio.phys_addr = frag->gpa;
11354 	if (vcpu->mmio_is_write)
11355 		memcpy(run->mmio.data, frag->data, min(8u, frag->len));
11356 	run->mmio.len = min(8u, frag->len);
11357 	run->mmio.is_write = vcpu->mmio_is_write;
11358 	vcpu->arch.complete_userspace_io = complete_emulated_mmio;
11359 	return 0;
11360 }
11361 
11362 /* Swap (qemu) user FPU context for the guest FPU context. */
kvm_load_guest_fpu(struct kvm_vcpu * vcpu)11363 static void kvm_load_guest_fpu(struct kvm_vcpu *vcpu)
11364 {
11365 	/* Exclude PKRU, it's restored separately immediately after VM-Exit. */
11366 	fpu_swap_kvm_fpstate(&vcpu->arch.guest_fpu, true);
11367 	trace_kvm_fpu(1);
11368 }
11369 
11370 /* When vcpu_run ends, restore user space FPU context. */
kvm_put_guest_fpu(struct kvm_vcpu * vcpu)11371 static void kvm_put_guest_fpu(struct kvm_vcpu *vcpu)
11372 {
11373 	fpu_swap_kvm_fpstate(&vcpu->arch.guest_fpu, false);
11374 	++vcpu->stat.fpu_reload;
11375 	trace_kvm_fpu(0);
11376 }
11377 
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)11378 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
11379 {
11380 	struct kvm_queued_exception *ex = &vcpu->arch.exception;
11381 	struct kvm_run *kvm_run = vcpu->run;
11382 	int r;
11383 
11384 	vcpu_load(vcpu);
11385 	kvm_sigset_activate(vcpu);
11386 	kvm_run->flags = 0;
11387 	kvm_load_guest_fpu(vcpu);
11388 
11389 	kvm_vcpu_srcu_read_lock(vcpu);
11390 	if (unlikely(vcpu->arch.mp_state == KVM_MP_STATE_UNINITIALIZED)) {
11391 		if (kvm_run->immediate_exit) {
11392 			r = -EINTR;
11393 			goto out;
11394 		}
11395 
11396 		/*
11397 		 * Don't bother switching APIC timer emulation from the
11398 		 * hypervisor timer to the software timer, the only way for the
11399 		 * APIC timer to be active is if userspace stuffed vCPU state,
11400 		 * i.e. put the vCPU into a nonsensical state.  Only an INIT
11401 		 * will transition the vCPU out of UNINITIALIZED (without more
11402 		 * state stuffing from userspace), which will reset the local
11403 		 * APIC and thus cancel the timer or drop the IRQ (if the timer
11404 		 * already expired).
11405 		 */
11406 		kvm_vcpu_srcu_read_unlock(vcpu);
11407 		kvm_vcpu_block(vcpu);
11408 		kvm_vcpu_srcu_read_lock(vcpu);
11409 
11410 		if (kvm_apic_accept_events(vcpu) < 0) {
11411 			r = 0;
11412 			goto out;
11413 		}
11414 		r = -EAGAIN;
11415 		if (signal_pending(current)) {
11416 			r = -EINTR;
11417 			kvm_run->exit_reason = KVM_EXIT_INTR;
11418 			++vcpu->stat.signal_exits;
11419 		}
11420 		goto out;
11421 	}
11422 
11423 	if ((kvm_run->kvm_valid_regs & ~KVM_SYNC_X86_VALID_FIELDS) ||
11424 	    (kvm_run->kvm_dirty_regs & ~KVM_SYNC_X86_VALID_FIELDS)) {
11425 		r = -EINVAL;
11426 		goto out;
11427 	}
11428 
11429 	if (kvm_run->kvm_dirty_regs) {
11430 		r = sync_regs(vcpu);
11431 		if (r != 0)
11432 			goto out;
11433 	}
11434 
11435 	/* re-sync apic's tpr */
11436 	if (!lapic_in_kernel(vcpu)) {
11437 		if (kvm_set_cr8(vcpu, kvm_run->cr8) != 0) {
11438 			r = -EINVAL;
11439 			goto out;
11440 		}
11441 	}
11442 
11443 	/*
11444 	 * If userspace set a pending exception and L2 is active, convert it to
11445 	 * a pending VM-Exit if L1 wants to intercept the exception.
11446 	 */
11447 	if (vcpu->arch.exception_from_userspace && is_guest_mode(vcpu) &&
11448 	    kvm_x86_ops.nested_ops->is_exception_vmexit(vcpu, ex->vector,
11449 							ex->error_code)) {
11450 		kvm_queue_exception_vmexit(vcpu, ex->vector,
11451 					   ex->has_error_code, ex->error_code,
11452 					   ex->has_payload, ex->payload);
11453 		ex->injected = false;
11454 		ex->pending = false;
11455 	}
11456 	vcpu->arch.exception_from_userspace = false;
11457 
11458 	if (unlikely(vcpu->arch.complete_userspace_io)) {
11459 		int (*cui)(struct kvm_vcpu *) = vcpu->arch.complete_userspace_io;
11460 		vcpu->arch.complete_userspace_io = NULL;
11461 		r = cui(vcpu);
11462 		if (r <= 0)
11463 			goto out;
11464 	} else {
11465 		WARN_ON_ONCE(vcpu->arch.pio.count);
11466 		WARN_ON_ONCE(vcpu->mmio_needed);
11467 	}
11468 
11469 	if (kvm_run->immediate_exit) {
11470 		r = -EINTR;
11471 		goto out;
11472 	}
11473 
11474 	r = static_call(kvm_x86_vcpu_pre_run)(vcpu);
11475 	if (r <= 0)
11476 		goto out;
11477 
11478 	r = vcpu_run(vcpu);
11479 
11480 out:
11481 	kvm_put_guest_fpu(vcpu);
11482 	if (kvm_run->kvm_valid_regs)
11483 		store_regs(vcpu);
11484 	post_kvm_run_save(vcpu);
11485 	kvm_vcpu_srcu_read_unlock(vcpu);
11486 
11487 	kvm_sigset_deactivate(vcpu);
11488 	vcpu_put(vcpu);
11489 	return r;
11490 }
11491 
__get_regs(struct kvm_vcpu * vcpu,struct kvm_regs * regs)11492 static void __get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
11493 {
11494 	if (vcpu->arch.emulate_regs_need_sync_to_vcpu) {
11495 		/*
11496 		 * We are here if userspace calls get_regs() in the middle of
11497 		 * instruction emulation. Registers state needs to be copied
11498 		 * back from emulation context to vcpu. Userspace shouldn't do
11499 		 * that usually, but some bad designed PV devices (vmware
11500 		 * backdoor interface) need this to work
11501 		 */
11502 		emulator_writeback_register_cache(vcpu->arch.emulate_ctxt);
11503 		vcpu->arch.emulate_regs_need_sync_to_vcpu = false;
11504 	}
11505 	regs->rax = kvm_rax_read(vcpu);
11506 	regs->rbx = kvm_rbx_read(vcpu);
11507 	regs->rcx = kvm_rcx_read(vcpu);
11508 	regs->rdx = kvm_rdx_read(vcpu);
11509 	regs->rsi = kvm_rsi_read(vcpu);
11510 	regs->rdi = kvm_rdi_read(vcpu);
11511 	regs->rsp = kvm_rsp_read(vcpu);
11512 	regs->rbp = kvm_rbp_read(vcpu);
11513 #ifdef CONFIG_X86_64
11514 	regs->r8 = kvm_r8_read(vcpu);
11515 	regs->r9 = kvm_r9_read(vcpu);
11516 	regs->r10 = kvm_r10_read(vcpu);
11517 	regs->r11 = kvm_r11_read(vcpu);
11518 	regs->r12 = kvm_r12_read(vcpu);
11519 	regs->r13 = kvm_r13_read(vcpu);
11520 	regs->r14 = kvm_r14_read(vcpu);
11521 	regs->r15 = kvm_r15_read(vcpu);
11522 #endif
11523 
11524 	regs->rip = kvm_rip_read(vcpu);
11525 	regs->rflags = kvm_get_rflags(vcpu);
11526 }
11527 
kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu * vcpu,struct kvm_regs * regs)11528 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
11529 {
11530 	if (vcpu->kvm->arch.has_protected_state &&
11531 	    vcpu->arch.guest_state_protected)
11532 		return -EINVAL;
11533 
11534 	vcpu_load(vcpu);
11535 	__get_regs(vcpu, regs);
11536 	vcpu_put(vcpu);
11537 	return 0;
11538 }
11539 
__set_regs(struct kvm_vcpu * vcpu,struct kvm_regs * regs)11540 static void __set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
11541 {
11542 	vcpu->arch.emulate_regs_need_sync_from_vcpu = true;
11543 	vcpu->arch.emulate_regs_need_sync_to_vcpu = false;
11544 
11545 	kvm_rax_write(vcpu, regs->rax);
11546 	kvm_rbx_write(vcpu, regs->rbx);
11547 	kvm_rcx_write(vcpu, regs->rcx);
11548 	kvm_rdx_write(vcpu, regs->rdx);
11549 	kvm_rsi_write(vcpu, regs->rsi);
11550 	kvm_rdi_write(vcpu, regs->rdi);
11551 	kvm_rsp_write(vcpu, regs->rsp);
11552 	kvm_rbp_write(vcpu, regs->rbp);
11553 #ifdef CONFIG_X86_64
11554 	kvm_r8_write(vcpu, regs->r8);
11555 	kvm_r9_write(vcpu, regs->r9);
11556 	kvm_r10_write(vcpu, regs->r10);
11557 	kvm_r11_write(vcpu, regs->r11);
11558 	kvm_r12_write(vcpu, regs->r12);
11559 	kvm_r13_write(vcpu, regs->r13);
11560 	kvm_r14_write(vcpu, regs->r14);
11561 	kvm_r15_write(vcpu, regs->r15);
11562 #endif
11563 
11564 	kvm_rip_write(vcpu, regs->rip);
11565 	kvm_set_rflags(vcpu, regs->rflags | X86_EFLAGS_FIXED);
11566 
11567 	vcpu->arch.exception.pending = false;
11568 	vcpu->arch.exception_vmexit.pending = false;
11569 
11570 	kvm_make_request(KVM_REQ_EVENT, vcpu);
11571 }
11572 
kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu * vcpu,struct kvm_regs * regs)11573 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
11574 {
11575 	if (vcpu->kvm->arch.has_protected_state &&
11576 	    vcpu->arch.guest_state_protected)
11577 		return -EINVAL;
11578 
11579 	vcpu_load(vcpu);
11580 	__set_regs(vcpu, regs);
11581 	vcpu_put(vcpu);
11582 	return 0;
11583 }
11584 
__get_sregs_common(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)11585 static void __get_sregs_common(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)
11586 {
11587 	struct desc_ptr dt;
11588 
11589 	if (vcpu->arch.guest_state_protected)
11590 		goto skip_protected_regs;
11591 
11592 	kvm_get_segment(vcpu, &sregs->cs, VCPU_SREG_CS);
11593 	kvm_get_segment(vcpu, &sregs->ds, VCPU_SREG_DS);
11594 	kvm_get_segment(vcpu, &sregs->es, VCPU_SREG_ES);
11595 	kvm_get_segment(vcpu, &sregs->fs, VCPU_SREG_FS);
11596 	kvm_get_segment(vcpu, &sregs->gs, VCPU_SREG_GS);
11597 	kvm_get_segment(vcpu, &sregs->ss, VCPU_SREG_SS);
11598 
11599 	kvm_get_segment(vcpu, &sregs->tr, VCPU_SREG_TR);
11600 	kvm_get_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR);
11601 
11602 	static_call(kvm_x86_get_idt)(vcpu, &dt);
11603 	sregs->idt.limit = dt.size;
11604 	sregs->idt.base = dt.address;
11605 	static_call(kvm_x86_get_gdt)(vcpu, &dt);
11606 	sregs->gdt.limit = dt.size;
11607 	sregs->gdt.base = dt.address;
11608 
11609 	sregs->cr2 = vcpu->arch.cr2;
11610 	sregs->cr3 = kvm_read_cr3(vcpu);
11611 
11612 skip_protected_regs:
11613 	sregs->cr0 = kvm_read_cr0(vcpu);
11614 	sregs->cr4 = kvm_read_cr4(vcpu);
11615 	sregs->cr8 = kvm_get_cr8(vcpu);
11616 	sregs->efer = vcpu->arch.efer;
11617 	sregs->apic_base = kvm_get_apic_base(vcpu);
11618 }
11619 
__get_sregs(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)11620 static void __get_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)
11621 {
11622 	__get_sregs_common(vcpu, sregs);
11623 
11624 	if (vcpu->arch.guest_state_protected)
11625 		return;
11626 
11627 	if (vcpu->arch.interrupt.injected && !vcpu->arch.interrupt.soft)
11628 		set_bit(vcpu->arch.interrupt.nr,
11629 			(unsigned long *)sregs->interrupt_bitmap);
11630 }
11631 
__get_sregs2(struct kvm_vcpu * vcpu,struct kvm_sregs2 * sregs2)11632 static void __get_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2)
11633 {
11634 	int i;
11635 
11636 	__get_sregs_common(vcpu, (struct kvm_sregs *)sregs2);
11637 
11638 	if (vcpu->arch.guest_state_protected)
11639 		return;
11640 
11641 	if (is_pae_paging(vcpu)) {
11642 		for (i = 0 ; i < 4 ; i++)
11643 			sregs2->pdptrs[i] = kvm_pdptr_read(vcpu, i);
11644 		sregs2->flags |= KVM_SREGS2_FLAGS_PDPTRS_VALID;
11645 	}
11646 }
11647 
kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)11648 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
11649 				  struct kvm_sregs *sregs)
11650 {
11651 	if (vcpu->kvm->arch.has_protected_state &&
11652 	    vcpu->arch.guest_state_protected)
11653 		return -EINVAL;
11654 
11655 	vcpu_load(vcpu);
11656 	__get_sregs(vcpu, sregs);
11657 	vcpu_put(vcpu);
11658 	return 0;
11659 }
11660 
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)11661 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
11662 				    struct kvm_mp_state *mp_state)
11663 {
11664 	int r;
11665 
11666 	vcpu_load(vcpu);
11667 	if (kvm_mpx_supported())
11668 		kvm_load_guest_fpu(vcpu);
11669 
11670 	r = kvm_apic_accept_events(vcpu);
11671 	if (r < 0)
11672 		goto out;
11673 	r = 0;
11674 
11675 	if ((vcpu->arch.mp_state == KVM_MP_STATE_HALTED ||
11676 	     vcpu->arch.mp_state == KVM_MP_STATE_AP_RESET_HOLD) &&
11677 	    vcpu->arch.pv.pv_unhalted)
11678 		mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
11679 	else
11680 		mp_state->mp_state = vcpu->arch.mp_state;
11681 
11682 out:
11683 	if (kvm_mpx_supported())
11684 		kvm_put_guest_fpu(vcpu);
11685 	vcpu_put(vcpu);
11686 	return r;
11687 }
11688 
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)11689 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
11690 				    struct kvm_mp_state *mp_state)
11691 {
11692 	int ret = -EINVAL;
11693 
11694 	vcpu_load(vcpu);
11695 
11696 	switch (mp_state->mp_state) {
11697 	case KVM_MP_STATE_UNINITIALIZED:
11698 	case KVM_MP_STATE_HALTED:
11699 	case KVM_MP_STATE_AP_RESET_HOLD:
11700 	case KVM_MP_STATE_INIT_RECEIVED:
11701 	case KVM_MP_STATE_SIPI_RECEIVED:
11702 		if (!lapic_in_kernel(vcpu))
11703 			goto out;
11704 		break;
11705 
11706 	case KVM_MP_STATE_RUNNABLE:
11707 		break;
11708 
11709 	default:
11710 		goto out;
11711 	}
11712 
11713 	/*
11714 	 * Pending INITs are reported using KVM_SET_VCPU_EVENTS, disallow
11715 	 * forcing the guest into INIT/SIPI if those events are supposed to be
11716 	 * blocked.  KVM prioritizes SMI over INIT, so reject INIT/SIPI state
11717 	 * if an SMI is pending as well.
11718 	 */
11719 	if ((!kvm_apic_init_sipi_allowed(vcpu) || vcpu->arch.smi_pending) &&
11720 	    (mp_state->mp_state == KVM_MP_STATE_SIPI_RECEIVED ||
11721 	     mp_state->mp_state == KVM_MP_STATE_INIT_RECEIVED))
11722 		goto out;
11723 
11724 	if (mp_state->mp_state == KVM_MP_STATE_SIPI_RECEIVED) {
11725 		vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED;
11726 		set_bit(KVM_APIC_SIPI, &vcpu->arch.apic->pending_events);
11727 	} else
11728 		vcpu->arch.mp_state = mp_state->mp_state;
11729 	kvm_make_request(KVM_REQ_EVENT, vcpu);
11730 
11731 	ret = 0;
11732 out:
11733 	vcpu_put(vcpu);
11734 	return ret;
11735 }
11736 
kvm_task_switch(struct kvm_vcpu * vcpu,u16 tss_selector,int idt_index,int reason,bool has_error_code,u32 error_code)11737 int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int idt_index,
11738 		    int reason, bool has_error_code, u32 error_code)
11739 {
11740 	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
11741 	int ret;
11742 
11743 	init_emulate_ctxt(vcpu);
11744 
11745 	ret = emulator_task_switch(ctxt, tss_selector, idt_index, reason,
11746 				   has_error_code, error_code);
11747 	if (ret) {
11748 		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
11749 		vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
11750 		vcpu->run->internal.ndata = 0;
11751 		return 0;
11752 	}
11753 
11754 	kvm_rip_write(vcpu, ctxt->eip);
11755 	kvm_set_rflags(vcpu, ctxt->eflags);
11756 	return 1;
11757 }
11758 EXPORT_SYMBOL_GPL(kvm_task_switch);
11759 
kvm_is_valid_sregs(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)11760 static bool kvm_is_valid_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)
11761 {
11762 	if ((sregs->efer & EFER_LME) && (sregs->cr0 & X86_CR0_PG)) {
11763 		/*
11764 		 * When EFER.LME and CR0.PG are set, the processor is in
11765 		 * 64-bit mode (though maybe in a 32-bit code segment).
11766 		 * CR4.PAE and EFER.LMA must be set.
11767 		 */
11768 		if (!(sregs->cr4 & X86_CR4_PAE) || !(sregs->efer & EFER_LMA))
11769 			return false;
11770 		if (!kvm_vcpu_is_legal_cr3(vcpu, sregs->cr3))
11771 			return false;
11772 	} else {
11773 		/*
11774 		 * Not in 64-bit mode: EFER.LMA is clear and the code
11775 		 * segment cannot be 64-bit.
11776 		 */
11777 		if (sregs->efer & EFER_LMA || sregs->cs.l)
11778 			return false;
11779 	}
11780 
11781 	return kvm_is_valid_cr4(vcpu, sregs->cr4) &&
11782 	       kvm_is_valid_cr0(vcpu, sregs->cr0);
11783 }
11784 
__set_sregs_common(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs,int * mmu_reset_needed,bool update_pdptrs)11785 static int __set_sregs_common(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs,
11786 		int *mmu_reset_needed, bool update_pdptrs)
11787 {
11788 	struct msr_data apic_base_msr;
11789 	int idx;
11790 	struct desc_ptr dt;
11791 
11792 	if (!kvm_is_valid_sregs(vcpu, sregs))
11793 		return -EINVAL;
11794 
11795 	apic_base_msr.data = sregs->apic_base;
11796 	apic_base_msr.host_initiated = true;
11797 	if (kvm_set_apic_base(vcpu, &apic_base_msr))
11798 		return -EINVAL;
11799 
11800 	if (vcpu->arch.guest_state_protected)
11801 		return 0;
11802 
11803 	dt.size = sregs->idt.limit;
11804 	dt.address = sregs->idt.base;
11805 	static_call(kvm_x86_set_idt)(vcpu, &dt);
11806 	dt.size = sregs->gdt.limit;
11807 	dt.address = sregs->gdt.base;
11808 	static_call(kvm_x86_set_gdt)(vcpu, &dt);
11809 
11810 	vcpu->arch.cr2 = sregs->cr2;
11811 	*mmu_reset_needed |= kvm_read_cr3(vcpu) != sregs->cr3;
11812 	vcpu->arch.cr3 = sregs->cr3;
11813 	kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3);
11814 	static_call_cond(kvm_x86_post_set_cr3)(vcpu, sregs->cr3);
11815 
11816 	kvm_set_cr8(vcpu, sregs->cr8);
11817 
11818 	*mmu_reset_needed |= vcpu->arch.efer != sregs->efer;
11819 	static_call(kvm_x86_set_efer)(vcpu, sregs->efer);
11820 
11821 	*mmu_reset_needed |= kvm_read_cr0(vcpu) != sregs->cr0;
11822 	static_call(kvm_x86_set_cr0)(vcpu, sregs->cr0);
11823 
11824 	*mmu_reset_needed |= kvm_read_cr4(vcpu) != sregs->cr4;
11825 	static_call(kvm_x86_set_cr4)(vcpu, sregs->cr4);
11826 
11827 	if (update_pdptrs) {
11828 		idx = srcu_read_lock(&vcpu->kvm->srcu);
11829 		if (is_pae_paging(vcpu)) {
11830 			load_pdptrs(vcpu, kvm_read_cr3(vcpu));
11831 			*mmu_reset_needed = 1;
11832 		}
11833 		srcu_read_unlock(&vcpu->kvm->srcu, idx);
11834 	}
11835 
11836 	kvm_set_segment(vcpu, &sregs->cs, VCPU_SREG_CS);
11837 	kvm_set_segment(vcpu, &sregs->ds, VCPU_SREG_DS);
11838 	kvm_set_segment(vcpu, &sregs->es, VCPU_SREG_ES);
11839 	kvm_set_segment(vcpu, &sregs->fs, VCPU_SREG_FS);
11840 	kvm_set_segment(vcpu, &sregs->gs, VCPU_SREG_GS);
11841 	kvm_set_segment(vcpu, &sregs->ss, VCPU_SREG_SS);
11842 
11843 	kvm_set_segment(vcpu, &sregs->tr, VCPU_SREG_TR);
11844 	kvm_set_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR);
11845 
11846 	update_cr8_intercept(vcpu);
11847 
11848 	/* Older userspace won't unhalt the vcpu on reset. */
11849 	if (kvm_vcpu_is_bsp(vcpu) && kvm_rip_read(vcpu) == 0xfff0 &&
11850 	    sregs->cs.selector == 0xf000 && sregs->cs.base == 0xffff0000 &&
11851 	    !is_protmode(vcpu))
11852 		vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
11853 
11854 	return 0;
11855 }
11856 
__set_sregs(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)11857 static int __set_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)
11858 {
11859 	int pending_vec, max_bits;
11860 	int mmu_reset_needed = 0;
11861 	int ret = __set_sregs_common(vcpu, sregs, &mmu_reset_needed, true);
11862 
11863 	if (ret)
11864 		return ret;
11865 
11866 	if (mmu_reset_needed) {
11867 		kvm_mmu_reset_context(vcpu);
11868 		kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
11869 	}
11870 
11871 	max_bits = KVM_NR_INTERRUPTS;
11872 	pending_vec = find_first_bit(
11873 		(const unsigned long *)sregs->interrupt_bitmap, max_bits);
11874 
11875 	if (pending_vec < max_bits) {
11876 		kvm_queue_interrupt(vcpu, pending_vec, false);
11877 		pr_debug("Set back pending irq %d\n", pending_vec);
11878 		kvm_make_request(KVM_REQ_EVENT, vcpu);
11879 	}
11880 	return 0;
11881 }
11882 
__set_sregs2(struct kvm_vcpu * vcpu,struct kvm_sregs2 * sregs2)11883 static int __set_sregs2(struct kvm_vcpu *vcpu, struct kvm_sregs2 *sregs2)
11884 {
11885 	int mmu_reset_needed = 0;
11886 	bool valid_pdptrs = sregs2->flags & KVM_SREGS2_FLAGS_PDPTRS_VALID;
11887 	bool pae = (sregs2->cr0 & X86_CR0_PG) && (sregs2->cr4 & X86_CR4_PAE) &&
11888 		!(sregs2->efer & EFER_LMA);
11889 	int i, ret;
11890 
11891 	if (sregs2->flags & ~KVM_SREGS2_FLAGS_PDPTRS_VALID)
11892 		return -EINVAL;
11893 
11894 	if (valid_pdptrs && (!pae || vcpu->arch.guest_state_protected))
11895 		return -EINVAL;
11896 
11897 	ret = __set_sregs_common(vcpu, (struct kvm_sregs *)sregs2,
11898 				 &mmu_reset_needed, !valid_pdptrs);
11899 	if (ret)
11900 		return ret;
11901 
11902 	if (valid_pdptrs) {
11903 		for (i = 0; i < 4 ; i++)
11904 			kvm_pdptr_write(vcpu, i, sregs2->pdptrs[i]);
11905 
11906 		kvm_register_mark_dirty(vcpu, VCPU_EXREG_PDPTR);
11907 		mmu_reset_needed = 1;
11908 		vcpu->arch.pdptrs_from_userspace = true;
11909 	}
11910 	if (mmu_reset_needed) {
11911 		kvm_mmu_reset_context(vcpu);
11912 		kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
11913 	}
11914 	return 0;
11915 }
11916 
kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu * vcpu,struct kvm_sregs * sregs)11917 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
11918 				  struct kvm_sregs *sregs)
11919 {
11920 	int ret;
11921 
11922 	if (vcpu->kvm->arch.has_protected_state &&
11923 	    vcpu->arch.guest_state_protected)
11924 		return -EINVAL;
11925 
11926 	vcpu_load(vcpu);
11927 	ret = __set_sregs(vcpu, sregs);
11928 	vcpu_put(vcpu);
11929 	return ret;
11930 }
11931 
kvm_arch_vcpu_guestdbg_update_apicv_inhibit(struct kvm * kvm)11932 static void kvm_arch_vcpu_guestdbg_update_apicv_inhibit(struct kvm *kvm)
11933 {
11934 	bool set = false;
11935 	struct kvm_vcpu *vcpu;
11936 	unsigned long i;
11937 
11938 	if (!enable_apicv)
11939 		return;
11940 
11941 	down_write(&kvm->arch.apicv_update_lock);
11942 
11943 	kvm_for_each_vcpu(i, vcpu, kvm) {
11944 		if (vcpu->guest_debug & KVM_GUESTDBG_BLOCKIRQ) {
11945 			set = true;
11946 			break;
11947 		}
11948 	}
11949 	__kvm_set_or_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_BLOCKIRQ, set);
11950 	up_write(&kvm->arch.apicv_update_lock);
11951 }
11952 
kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu * vcpu,struct kvm_guest_debug * dbg)11953 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
11954 					struct kvm_guest_debug *dbg)
11955 {
11956 	unsigned long rflags;
11957 	int i, r;
11958 
11959 	if (vcpu->arch.guest_state_protected)
11960 		return -EINVAL;
11961 
11962 	vcpu_load(vcpu);
11963 
11964 	if (dbg->control & (KVM_GUESTDBG_INJECT_DB | KVM_GUESTDBG_INJECT_BP)) {
11965 		r = -EBUSY;
11966 		if (kvm_is_exception_pending(vcpu))
11967 			goto out;
11968 		if (dbg->control & KVM_GUESTDBG_INJECT_DB)
11969 			kvm_queue_exception(vcpu, DB_VECTOR);
11970 		else
11971 			kvm_queue_exception(vcpu, BP_VECTOR);
11972 	}
11973 
11974 	/*
11975 	 * Read rflags as long as potentially injected trace flags are still
11976 	 * filtered out.
11977 	 */
11978 	rflags = kvm_get_rflags(vcpu);
11979 
11980 	vcpu->guest_debug = dbg->control;
11981 	if (!(vcpu->guest_debug & KVM_GUESTDBG_ENABLE))
11982 		vcpu->guest_debug = 0;
11983 
11984 	if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP) {
11985 		for (i = 0; i < KVM_NR_DB_REGS; ++i)
11986 			vcpu->arch.eff_db[i] = dbg->arch.debugreg[i];
11987 		vcpu->arch.guest_debug_dr7 = dbg->arch.debugreg[7];
11988 	} else {
11989 		for (i = 0; i < KVM_NR_DB_REGS; i++)
11990 			vcpu->arch.eff_db[i] = vcpu->arch.db[i];
11991 	}
11992 	kvm_update_dr7(vcpu);
11993 
11994 	if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
11995 		vcpu->arch.singlestep_rip = kvm_get_linear_rip(vcpu);
11996 
11997 	/*
11998 	 * Trigger an rflags update that will inject or remove the trace
11999 	 * flags.
12000 	 */
12001 	kvm_set_rflags(vcpu, rflags);
12002 
12003 	static_call(kvm_x86_update_exception_bitmap)(vcpu);
12004 
12005 	kvm_arch_vcpu_guestdbg_update_apicv_inhibit(vcpu->kvm);
12006 
12007 	r = 0;
12008 
12009 out:
12010 	vcpu_put(vcpu);
12011 	return r;
12012 }
12013 
12014 /*
12015  * Translate a guest virtual address to a guest physical address.
12016  */
kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu * vcpu,struct kvm_translation * tr)12017 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
12018 				    struct kvm_translation *tr)
12019 {
12020 	unsigned long vaddr = tr->linear_address;
12021 	gpa_t gpa;
12022 	int idx;
12023 
12024 	vcpu_load(vcpu);
12025 
12026 	idx = srcu_read_lock(&vcpu->kvm->srcu);
12027 	gpa = kvm_mmu_gva_to_gpa_system(vcpu, vaddr, NULL);
12028 	srcu_read_unlock(&vcpu->kvm->srcu, idx);
12029 	tr->physical_address = gpa;
12030 	tr->valid = gpa != INVALID_GPA;
12031 	tr->writeable = 1;
12032 	tr->usermode = 0;
12033 
12034 	vcpu_put(vcpu);
12035 	return 0;
12036 }
12037 
kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu * vcpu,struct kvm_fpu * fpu)12038 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
12039 {
12040 	struct fxregs_state *fxsave;
12041 
12042 	if (fpstate_is_confidential(&vcpu->arch.guest_fpu))
12043 		return vcpu->kvm->arch.has_protected_state ? -EINVAL : 0;
12044 
12045 	vcpu_load(vcpu);
12046 
12047 	fxsave = &vcpu->arch.guest_fpu.fpstate->regs.fxsave;
12048 	memcpy(fpu->fpr, fxsave->st_space, 128);
12049 	fpu->fcw = fxsave->cwd;
12050 	fpu->fsw = fxsave->swd;
12051 	fpu->ftwx = fxsave->twd;
12052 	fpu->last_opcode = fxsave->fop;
12053 	fpu->last_ip = fxsave->rip;
12054 	fpu->last_dp = fxsave->rdp;
12055 	memcpy(fpu->xmm, fxsave->xmm_space, sizeof(fxsave->xmm_space));
12056 
12057 	vcpu_put(vcpu);
12058 	return 0;
12059 }
12060 
kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu * vcpu,struct kvm_fpu * fpu)12061 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
12062 {
12063 	struct fxregs_state *fxsave;
12064 
12065 	if (fpstate_is_confidential(&vcpu->arch.guest_fpu))
12066 		return vcpu->kvm->arch.has_protected_state ? -EINVAL : 0;
12067 
12068 	vcpu_load(vcpu);
12069 
12070 	fxsave = &vcpu->arch.guest_fpu.fpstate->regs.fxsave;
12071 
12072 	memcpy(fxsave->st_space, fpu->fpr, 128);
12073 	fxsave->cwd = fpu->fcw;
12074 	fxsave->swd = fpu->fsw;
12075 	fxsave->twd = fpu->ftwx;
12076 	fxsave->fop = fpu->last_opcode;
12077 	fxsave->rip = fpu->last_ip;
12078 	fxsave->rdp = fpu->last_dp;
12079 	memcpy(fxsave->xmm_space, fpu->xmm, sizeof(fxsave->xmm_space));
12080 
12081 	vcpu_put(vcpu);
12082 	return 0;
12083 }
12084 
store_regs(struct kvm_vcpu * vcpu)12085 static void store_regs(struct kvm_vcpu *vcpu)
12086 {
12087 	BUILD_BUG_ON(sizeof(struct kvm_sync_regs) > SYNC_REGS_SIZE_BYTES);
12088 
12089 	if (vcpu->run->kvm_valid_regs & KVM_SYNC_X86_REGS)
12090 		__get_regs(vcpu, &vcpu->run->s.regs.regs);
12091 
12092 	if (vcpu->run->kvm_valid_regs & KVM_SYNC_X86_SREGS)
12093 		__get_sregs(vcpu, &vcpu->run->s.regs.sregs);
12094 
12095 	if (vcpu->run->kvm_valid_regs & KVM_SYNC_X86_EVENTS)
12096 		kvm_vcpu_ioctl_x86_get_vcpu_events(
12097 				vcpu, &vcpu->run->s.regs.events);
12098 }
12099 
sync_regs(struct kvm_vcpu * vcpu)12100 static int sync_regs(struct kvm_vcpu *vcpu)
12101 {
12102 	if (vcpu->run->kvm_dirty_regs & KVM_SYNC_X86_REGS) {
12103 		__set_regs(vcpu, &vcpu->run->s.regs.regs);
12104 		vcpu->run->kvm_dirty_regs &= ~KVM_SYNC_X86_REGS;
12105 	}
12106 
12107 	if (vcpu->run->kvm_dirty_regs & KVM_SYNC_X86_SREGS) {
12108 		struct kvm_sregs sregs = vcpu->run->s.regs.sregs;
12109 
12110 		if (__set_sregs(vcpu, &sregs))
12111 			return -EINVAL;
12112 
12113 		vcpu->run->kvm_dirty_regs &= ~KVM_SYNC_X86_SREGS;
12114 	}
12115 
12116 	if (vcpu->run->kvm_dirty_regs & KVM_SYNC_X86_EVENTS) {
12117 		struct kvm_vcpu_events events = vcpu->run->s.regs.events;
12118 
12119 		if (kvm_vcpu_ioctl_x86_set_vcpu_events(vcpu, &events))
12120 			return -EINVAL;
12121 
12122 		vcpu->run->kvm_dirty_regs &= ~KVM_SYNC_X86_EVENTS;
12123 	}
12124 
12125 	return 0;
12126 }
12127 
kvm_arch_vcpu_precreate(struct kvm * kvm,unsigned int id)12128 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
12129 {
12130 	if (kvm_check_tsc_unstable() && kvm->created_vcpus)
12131 		pr_warn_once("SMP vm created on host with unstable TSC; "
12132 			     "guest TSC will not be reliable\n");
12133 
12134 	if (!kvm->arch.max_vcpu_ids)
12135 		kvm->arch.max_vcpu_ids = KVM_MAX_VCPU_IDS;
12136 
12137 	if (id >= kvm->arch.max_vcpu_ids)
12138 		return -EINVAL;
12139 
12140 	return static_call(kvm_x86_vcpu_precreate)(kvm);
12141 }
12142 
kvm_arch_vcpu_create(struct kvm_vcpu * vcpu)12143 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
12144 {
12145 	struct page *page;
12146 	int r;
12147 
12148 	vcpu->arch.last_vmentry_cpu = -1;
12149 	vcpu->arch.regs_avail = ~0;
12150 	vcpu->arch.regs_dirty = ~0;
12151 
12152 	kvm_gpc_init(&vcpu->arch.pv_time, vcpu->kvm);
12153 
12154 	if (!irqchip_in_kernel(vcpu->kvm) || kvm_vcpu_is_reset_bsp(vcpu))
12155 		vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
12156 	else
12157 		vcpu->arch.mp_state = KVM_MP_STATE_UNINITIALIZED;
12158 
12159 	r = kvm_mmu_create(vcpu);
12160 	if (r < 0)
12161 		return r;
12162 
12163 	r = kvm_create_lapic(vcpu);
12164 	if (r < 0)
12165 		goto fail_mmu_destroy;
12166 
12167 	r = -ENOMEM;
12168 
12169 	page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
12170 	if (!page)
12171 		goto fail_free_lapic;
12172 	vcpu->arch.pio_data = page_address(page);
12173 
12174 	vcpu->arch.mce_banks = kcalloc(KVM_MAX_MCE_BANKS * 4, sizeof(u64),
12175 				       GFP_KERNEL_ACCOUNT);
12176 	vcpu->arch.mci_ctl2_banks = kcalloc(KVM_MAX_MCE_BANKS, sizeof(u64),
12177 					    GFP_KERNEL_ACCOUNT);
12178 	if (!vcpu->arch.mce_banks || !vcpu->arch.mci_ctl2_banks)
12179 		goto fail_free_mce_banks;
12180 	vcpu->arch.mcg_cap = KVM_MAX_MCE_BANKS;
12181 
12182 	if (!zalloc_cpumask_var(&vcpu->arch.wbinvd_dirty_mask,
12183 				GFP_KERNEL_ACCOUNT))
12184 		goto fail_free_mce_banks;
12185 
12186 	if (!alloc_emulate_ctxt(vcpu))
12187 		goto free_wbinvd_dirty_mask;
12188 
12189 	if (!fpu_alloc_guest_fpstate(&vcpu->arch.guest_fpu)) {
12190 		pr_err("failed to allocate vcpu's fpu\n");
12191 		goto free_emulate_ctxt;
12192 	}
12193 
12194 	vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
12195 	vcpu->arch.reserved_gpa_bits = kvm_vcpu_reserved_gpa_bits_raw(vcpu);
12196 
12197 	vcpu->arch.pat = MSR_IA32_CR_PAT_DEFAULT;
12198 
12199 	kvm_async_pf_hash_reset(vcpu);
12200 
12201 	vcpu->arch.perf_capabilities = kvm_caps.supported_perf_cap;
12202 	kvm_pmu_init(vcpu);
12203 
12204 	vcpu->arch.pending_external_vector = -1;
12205 	vcpu->arch.preempted_in_kernel = false;
12206 
12207 #if IS_ENABLED(CONFIG_HYPERV)
12208 	vcpu->arch.hv_root_tdp = INVALID_PAGE;
12209 #endif
12210 
12211 	r = static_call(kvm_x86_vcpu_create)(vcpu);
12212 	if (r)
12213 		goto free_guest_fpu;
12214 
12215 	vcpu->arch.arch_capabilities = kvm_get_arch_capabilities();
12216 	vcpu->arch.msr_platform_info = MSR_PLATFORM_INFO_CPUID_FAULT;
12217 	kvm_xen_init_vcpu(vcpu);
12218 	kvm_vcpu_mtrr_init(vcpu);
12219 	vcpu_load(vcpu);
12220 	kvm_set_tsc_khz(vcpu, vcpu->kvm->arch.default_tsc_khz);
12221 	kvm_vcpu_reset(vcpu, false);
12222 	kvm_init_mmu(vcpu);
12223 	vcpu_put(vcpu);
12224 	return 0;
12225 
12226 free_guest_fpu:
12227 	fpu_free_guest_fpstate(&vcpu->arch.guest_fpu);
12228 free_emulate_ctxt:
12229 	kmem_cache_free(x86_emulator_cache, vcpu->arch.emulate_ctxt);
12230 free_wbinvd_dirty_mask:
12231 	free_cpumask_var(vcpu->arch.wbinvd_dirty_mask);
12232 fail_free_mce_banks:
12233 	kfree(vcpu->arch.mce_banks);
12234 	kfree(vcpu->arch.mci_ctl2_banks);
12235 	free_page((unsigned long)vcpu->arch.pio_data);
12236 fail_free_lapic:
12237 	kvm_free_lapic(vcpu);
12238 fail_mmu_destroy:
12239 	kvm_mmu_destroy(vcpu);
12240 	return r;
12241 }
12242 
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)12243 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
12244 {
12245 	struct kvm *kvm = vcpu->kvm;
12246 
12247 	if (mutex_lock_killable(&vcpu->mutex))
12248 		return;
12249 	vcpu_load(vcpu);
12250 	kvm_synchronize_tsc(vcpu, NULL);
12251 	vcpu_put(vcpu);
12252 
12253 	/* poll control enabled by default */
12254 	vcpu->arch.msr_kvm_poll_control = 1;
12255 
12256 	mutex_unlock(&vcpu->mutex);
12257 
12258 	if (kvmclock_periodic_sync && vcpu->vcpu_idx == 0)
12259 		schedule_delayed_work(&kvm->arch.kvmclock_sync_work,
12260 						KVMCLOCK_SYNC_PERIOD);
12261 }
12262 
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)12263 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
12264 {
12265 	int idx;
12266 
12267 	kvmclock_reset(vcpu);
12268 
12269 	static_call(kvm_x86_vcpu_free)(vcpu);
12270 
12271 	kmem_cache_free(x86_emulator_cache, vcpu->arch.emulate_ctxt);
12272 	free_cpumask_var(vcpu->arch.wbinvd_dirty_mask);
12273 	fpu_free_guest_fpstate(&vcpu->arch.guest_fpu);
12274 
12275 	kvm_xen_destroy_vcpu(vcpu);
12276 	kvm_hv_vcpu_uninit(vcpu);
12277 	kvm_pmu_destroy(vcpu);
12278 	kfree(vcpu->arch.mce_banks);
12279 	kfree(vcpu->arch.mci_ctl2_banks);
12280 	kvm_free_lapic(vcpu);
12281 	idx = srcu_read_lock(&vcpu->kvm->srcu);
12282 	kvm_mmu_destroy(vcpu);
12283 	srcu_read_unlock(&vcpu->kvm->srcu, idx);
12284 	free_page((unsigned long)vcpu->arch.pio_data);
12285 	kvfree(vcpu->arch.cpuid_entries);
12286 }
12287 
kvm_vcpu_reset(struct kvm_vcpu * vcpu,bool init_event)12288 void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
12289 {
12290 	struct kvm_cpuid_entry2 *cpuid_0x1;
12291 	unsigned long old_cr0 = kvm_read_cr0(vcpu);
12292 	unsigned long new_cr0;
12293 
12294 	/*
12295 	 * Several of the "set" flows, e.g. ->set_cr0(), read other registers
12296 	 * to handle side effects.  RESET emulation hits those flows and relies
12297 	 * on emulated/virtualized registers, including those that are loaded
12298 	 * into hardware, to be zeroed at vCPU creation.  Use CRs as a sentinel
12299 	 * to detect improper or missing initialization.
12300 	 */
12301 	WARN_ON_ONCE(!init_event &&
12302 		     (old_cr0 || kvm_read_cr3(vcpu) || kvm_read_cr4(vcpu)));
12303 
12304 	/*
12305 	 * SVM doesn't unconditionally VM-Exit on INIT and SHUTDOWN, thus it's
12306 	 * possible to INIT the vCPU while L2 is active.  Force the vCPU back
12307 	 * into L1 as EFER.SVME is cleared on INIT (along with all other EFER
12308 	 * bits), i.e. virtualization is disabled.
12309 	 */
12310 	if (is_guest_mode(vcpu))
12311 		kvm_leave_nested(vcpu);
12312 
12313 	kvm_lapic_reset(vcpu, init_event);
12314 
12315 	WARN_ON_ONCE(is_guest_mode(vcpu) || is_smm(vcpu));
12316 	vcpu->arch.hflags = 0;
12317 
12318 	vcpu->arch.smi_pending = 0;
12319 	vcpu->arch.smi_count = 0;
12320 	atomic_set(&vcpu->arch.nmi_queued, 0);
12321 	vcpu->arch.nmi_pending = 0;
12322 	vcpu->arch.nmi_injected = false;
12323 	kvm_clear_interrupt_queue(vcpu);
12324 	kvm_clear_exception_queue(vcpu);
12325 
12326 	memset(vcpu->arch.db, 0, sizeof(vcpu->arch.db));
12327 	kvm_update_dr0123(vcpu);
12328 	vcpu->arch.dr6 = DR6_ACTIVE_LOW;
12329 	vcpu->arch.dr7 = DR7_FIXED_1;
12330 	kvm_update_dr7(vcpu);
12331 
12332 	vcpu->arch.cr2 = 0;
12333 
12334 	kvm_make_request(KVM_REQ_EVENT, vcpu);
12335 	vcpu->arch.apf.msr_en_val = 0;
12336 	vcpu->arch.apf.msr_int_val = 0;
12337 	vcpu->arch.st.msr_val = 0;
12338 
12339 	kvmclock_reset(vcpu);
12340 
12341 	kvm_clear_async_pf_completion_queue(vcpu);
12342 	kvm_async_pf_hash_reset(vcpu);
12343 	vcpu->arch.apf.halted = false;
12344 
12345 	if (vcpu->arch.guest_fpu.fpstate && kvm_mpx_supported()) {
12346 		struct fpstate *fpstate = vcpu->arch.guest_fpu.fpstate;
12347 
12348 		/*
12349 		 * All paths that lead to INIT are required to load the guest's
12350 		 * FPU state (because most paths are buried in KVM_RUN).
12351 		 */
12352 		if (init_event)
12353 			kvm_put_guest_fpu(vcpu);
12354 
12355 		fpstate_clear_xstate_component(fpstate, XFEATURE_BNDREGS);
12356 		fpstate_clear_xstate_component(fpstate, XFEATURE_BNDCSR);
12357 
12358 		if (init_event)
12359 			kvm_load_guest_fpu(vcpu);
12360 	}
12361 
12362 	if (!init_event) {
12363 		vcpu->arch.smbase = 0x30000;
12364 
12365 		vcpu->arch.msr_misc_features_enables = 0;
12366 		vcpu->arch.ia32_misc_enable_msr = MSR_IA32_MISC_ENABLE_PEBS_UNAVAIL |
12367 						  MSR_IA32_MISC_ENABLE_BTS_UNAVAIL;
12368 
12369 		__kvm_set_xcr(vcpu, 0, XFEATURE_MASK_FP);
12370 		__kvm_set_msr(vcpu, MSR_IA32_XSS, 0, true);
12371 	}
12372 
12373 	/* All GPRs except RDX (handled below) are zeroed on RESET/INIT. */
12374 	memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs));
12375 	kvm_register_mark_dirty(vcpu, VCPU_REGS_RSP);
12376 
12377 	/*
12378 	 * Fall back to KVM's default Family/Model/Stepping of 0x600 (P6/Athlon)
12379 	 * if no CPUID match is found.  Note, it's impossible to get a match at
12380 	 * RESET since KVM emulates RESET before exposing the vCPU to userspace,
12381 	 * i.e. it's impossible for kvm_find_cpuid_entry() to find a valid entry
12382 	 * on RESET.  But, go through the motions in case that's ever remedied.
12383 	 */
12384 	cpuid_0x1 = kvm_find_cpuid_entry(vcpu, 1);
12385 	kvm_rdx_write(vcpu, cpuid_0x1 ? cpuid_0x1->eax : 0x600);
12386 
12387 	static_call(kvm_x86_vcpu_reset)(vcpu, init_event);
12388 
12389 	kvm_set_rflags(vcpu, X86_EFLAGS_FIXED);
12390 	kvm_rip_write(vcpu, 0xfff0);
12391 
12392 	vcpu->arch.cr3 = 0;
12393 	kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3);
12394 
12395 	/*
12396 	 * CR0.CD/NW are set on RESET, preserved on INIT.  Note, some versions
12397 	 * of Intel's SDM list CD/NW as being set on INIT, but they contradict
12398 	 * (or qualify) that with a footnote stating that CD/NW are preserved.
12399 	 */
12400 	new_cr0 = X86_CR0_ET;
12401 	if (init_event)
12402 		new_cr0 |= (old_cr0 & (X86_CR0_NW | X86_CR0_CD));
12403 	else
12404 		new_cr0 |= X86_CR0_NW | X86_CR0_CD;
12405 
12406 	static_call(kvm_x86_set_cr0)(vcpu, new_cr0);
12407 	static_call(kvm_x86_set_cr4)(vcpu, 0);
12408 	static_call(kvm_x86_set_efer)(vcpu, 0);
12409 	static_call(kvm_x86_update_exception_bitmap)(vcpu);
12410 
12411 	/*
12412 	 * On the standard CR0/CR4/EFER modification paths, there are several
12413 	 * complex conditions determining whether the MMU has to be reset and/or
12414 	 * which PCIDs have to be flushed.  However, CR0.WP and the paging-related
12415 	 * bits in CR4 and EFER are irrelevant if CR0.PG was '0'; and a reset+flush
12416 	 * is needed anyway if CR0.PG was '1' (which can only happen for INIT, as
12417 	 * CR0 will be '0' prior to RESET).  So we only need to check CR0.PG here.
12418 	 */
12419 	if (old_cr0 & X86_CR0_PG) {
12420 		kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
12421 		kvm_mmu_reset_context(vcpu);
12422 	}
12423 
12424 	/*
12425 	 * Intel's SDM states that all TLB entries are flushed on INIT.  AMD's
12426 	 * APM states the TLBs are untouched by INIT, but it also states that
12427 	 * the TLBs are flushed on "External initialization of the processor."
12428 	 * Flush the guest TLB regardless of vendor, there is no meaningful
12429 	 * benefit in relying on the guest to flush the TLB immediately after
12430 	 * INIT.  A spurious TLB flush is benign and likely negligible from a
12431 	 * performance perspective.
12432 	 */
12433 	if (init_event)
12434 		kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
12435 }
12436 EXPORT_SYMBOL_GPL(kvm_vcpu_reset);
12437 
kvm_vcpu_deliver_sipi_vector(struct kvm_vcpu * vcpu,u8 vector)12438 void kvm_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector)
12439 {
12440 	struct kvm_segment cs;
12441 
12442 	kvm_get_segment(vcpu, &cs, VCPU_SREG_CS);
12443 	cs.selector = vector << 8;
12444 	cs.base = vector << 12;
12445 	kvm_set_segment(vcpu, &cs, VCPU_SREG_CS);
12446 	kvm_rip_write(vcpu, 0);
12447 }
12448 EXPORT_SYMBOL_GPL(kvm_vcpu_deliver_sipi_vector);
12449 
kvm_arch_hardware_enable(void)12450 int kvm_arch_hardware_enable(void)
12451 {
12452 	struct kvm *kvm;
12453 	struct kvm_vcpu *vcpu;
12454 	unsigned long i;
12455 	int ret;
12456 	u64 local_tsc;
12457 	u64 max_tsc = 0;
12458 	bool stable, backwards_tsc = false;
12459 
12460 	kvm_user_return_msr_cpu_online();
12461 
12462 	ret = kvm_x86_check_processor_compatibility();
12463 	if (ret)
12464 		return ret;
12465 
12466 	ret = static_call(kvm_x86_hardware_enable)();
12467 	if (ret != 0)
12468 		return ret;
12469 
12470 	local_tsc = rdtsc();
12471 	stable = !kvm_check_tsc_unstable();
12472 	list_for_each_entry(kvm, &vm_list, vm_list) {
12473 		kvm_for_each_vcpu(i, vcpu, kvm) {
12474 			if (!stable && vcpu->cpu == smp_processor_id())
12475 				kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
12476 			if (stable && vcpu->arch.last_host_tsc > local_tsc) {
12477 				backwards_tsc = true;
12478 				if (vcpu->arch.last_host_tsc > max_tsc)
12479 					max_tsc = vcpu->arch.last_host_tsc;
12480 			}
12481 		}
12482 	}
12483 
12484 	/*
12485 	 * Sometimes, even reliable TSCs go backwards.  This happens on
12486 	 * platforms that reset TSC during suspend or hibernate actions, but
12487 	 * maintain synchronization.  We must compensate.  Fortunately, we can
12488 	 * detect that condition here, which happens early in CPU bringup,
12489 	 * before any KVM threads can be running.  Unfortunately, we can't
12490 	 * bring the TSCs fully up to date with real time, as we aren't yet far
12491 	 * enough into CPU bringup that we know how much real time has actually
12492 	 * elapsed; our helper function, ktime_get_boottime_ns() will be using boot
12493 	 * variables that haven't been updated yet.
12494 	 *
12495 	 * So we simply find the maximum observed TSC above, then record the
12496 	 * adjustment to TSC in each VCPU.  When the VCPU later gets loaded,
12497 	 * the adjustment will be applied.  Note that we accumulate
12498 	 * adjustments, in case multiple suspend cycles happen before some VCPU
12499 	 * gets a chance to run again.  In the event that no KVM threads get a
12500 	 * chance to run, we will miss the entire elapsed period, as we'll have
12501 	 * reset last_host_tsc, so VCPUs will not have the TSC adjusted and may
12502 	 * loose cycle time.  This isn't too big a deal, since the loss will be
12503 	 * uniform across all VCPUs (not to mention the scenario is extremely
12504 	 * unlikely). It is possible that a second hibernate recovery happens
12505 	 * much faster than a first, causing the observed TSC here to be
12506 	 * smaller; this would require additional padding adjustment, which is
12507 	 * why we set last_host_tsc to the local tsc observed here.
12508 	 *
12509 	 * N.B. - this code below runs only on platforms with reliable TSC,
12510 	 * as that is the only way backwards_tsc is set above.  Also note
12511 	 * that this runs for ALL vcpus, which is not a bug; all VCPUs should
12512 	 * have the same delta_cyc adjustment applied if backwards_tsc
12513 	 * is detected.  Note further, this adjustment is only done once,
12514 	 * as we reset last_host_tsc on all VCPUs to stop this from being
12515 	 * called multiple times (one for each physical CPU bringup).
12516 	 *
12517 	 * Platforms with unreliable TSCs don't have to deal with this, they
12518 	 * will be compensated by the logic in vcpu_load, which sets the TSC to
12519 	 * catchup mode.  This will catchup all VCPUs to real time, but cannot
12520 	 * guarantee that they stay in perfect synchronization.
12521 	 */
12522 	if (backwards_tsc) {
12523 		u64 delta_cyc = max_tsc - local_tsc;
12524 		list_for_each_entry(kvm, &vm_list, vm_list) {
12525 			kvm->arch.backwards_tsc_observed = true;
12526 			kvm_for_each_vcpu(i, vcpu, kvm) {
12527 				vcpu->arch.tsc_offset_adjustment += delta_cyc;
12528 				vcpu->arch.last_host_tsc = local_tsc;
12529 				kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu);
12530 			}
12531 
12532 			/*
12533 			 * We have to disable TSC offset matching.. if you were
12534 			 * booting a VM while issuing an S4 host suspend....
12535 			 * you may have some problem.  Solving this issue is
12536 			 * left as an exercise to the reader.
12537 			 */
12538 			kvm->arch.last_tsc_nsec = 0;
12539 			kvm->arch.last_tsc_write = 0;
12540 		}
12541 
12542 	}
12543 	return 0;
12544 }
12545 
kvm_arch_hardware_disable(void)12546 void kvm_arch_hardware_disable(void)
12547 {
12548 	static_call(kvm_x86_hardware_disable)();
12549 	drop_user_return_notifiers();
12550 }
12551 
kvm_vcpu_is_reset_bsp(struct kvm_vcpu * vcpu)12552 bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu)
12553 {
12554 	return vcpu->kvm->arch.bsp_vcpu_id == vcpu->vcpu_id;
12555 }
12556 
kvm_vcpu_is_bsp(struct kvm_vcpu * vcpu)12557 bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu)
12558 {
12559 	return (vcpu->arch.apic_base & MSR_IA32_APICBASE_BSP) != 0;
12560 }
12561 
kvm_arch_sched_in(struct kvm_vcpu * vcpu,int cpu)12562 void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu)
12563 {
12564 	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
12565 
12566 	vcpu->arch.l1tf_flush_l1d = true;
12567 	if (pmu->version && unlikely(pmu->event_count)) {
12568 		pmu->need_cleanup = true;
12569 		kvm_make_request(KVM_REQ_PMU, vcpu);
12570 	}
12571 	static_call(kvm_x86_sched_in)(vcpu, cpu);
12572 }
12573 
kvm_arch_free_vm(struct kvm * kvm)12574 void kvm_arch_free_vm(struct kvm *kvm)
12575 {
12576 #if IS_ENABLED(CONFIG_HYPERV)
12577 	kfree(kvm->arch.hv_pa_pg);
12578 #endif
12579 	__kvm_arch_free_vm(kvm);
12580 }
12581 
12582 
kvm_arch_init_vm(struct kvm * kvm,unsigned long type)12583 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
12584 {
12585 	int ret;
12586 	unsigned long flags;
12587 
12588 	if (!kvm_is_vm_type_supported(type))
12589 		return -EINVAL;
12590 
12591 	kvm->arch.vm_type = type;
12592 	kvm->arch.has_private_mem =
12593 		(type == KVM_X86_SW_PROTECTED_VM);
12594 
12595 	ret = kvm_page_track_init(kvm);
12596 	if (ret)
12597 		goto out;
12598 
12599 	kvm_mmu_init_vm(kvm);
12600 
12601 	ret = static_call(kvm_x86_vm_init)(kvm);
12602 	if (ret)
12603 		goto out_uninit_mmu;
12604 
12605 	INIT_HLIST_HEAD(&kvm->arch.mask_notifier_list);
12606 	atomic_set(&kvm->arch.noncoherent_dma_count, 0);
12607 
12608 	/* Reserve bit 0 of irq_sources_bitmap for userspace irq source */
12609 	set_bit(KVM_USERSPACE_IRQ_SOURCE_ID, &kvm->arch.irq_sources_bitmap);
12610 	/* Reserve bit 1 of irq_sources_bitmap for irqfd-resampler */
12611 	set_bit(KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID,
12612 		&kvm->arch.irq_sources_bitmap);
12613 
12614 	raw_spin_lock_init(&kvm->arch.tsc_write_lock);
12615 	mutex_init(&kvm->arch.apic_map_lock);
12616 	seqcount_raw_spinlock_init(&kvm->arch.pvclock_sc, &kvm->arch.tsc_write_lock);
12617 	kvm->arch.kvmclock_offset = -get_kvmclock_base_ns();
12618 
12619 	raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags);
12620 	pvclock_update_vm_gtod_copy(kvm);
12621 	raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags);
12622 
12623 	kvm->arch.default_tsc_khz = max_tsc_khz ? : tsc_khz;
12624 	kvm->arch.guest_can_read_msr_platform_info = true;
12625 	kvm->arch.enable_pmu = enable_pmu;
12626 
12627 #if IS_ENABLED(CONFIG_HYPERV)
12628 	spin_lock_init(&kvm->arch.hv_root_tdp_lock);
12629 	kvm->arch.hv_root_tdp = INVALID_PAGE;
12630 #endif
12631 
12632 	INIT_DELAYED_WORK(&kvm->arch.kvmclock_update_work, kvmclock_update_fn);
12633 	INIT_DELAYED_WORK(&kvm->arch.kvmclock_sync_work, kvmclock_sync_fn);
12634 
12635 	kvm_apicv_init(kvm);
12636 	kvm_hv_init_vm(kvm);
12637 	kvm_xen_init_vm(kvm);
12638 
12639 	return 0;
12640 
12641 out_uninit_mmu:
12642 	kvm_mmu_uninit_vm(kvm);
12643 	kvm_page_track_cleanup(kvm);
12644 out:
12645 	return ret;
12646 }
12647 
kvm_arch_post_init_vm(struct kvm * kvm)12648 int kvm_arch_post_init_vm(struct kvm *kvm)
12649 {
12650 	return kvm_mmu_post_init_vm(kvm);
12651 }
12652 
kvm_unload_vcpu_mmu(struct kvm_vcpu * vcpu)12653 static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu)
12654 {
12655 	vcpu_load(vcpu);
12656 	kvm_mmu_unload(vcpu);
12657 	vcpu_put(vcpu);
12658 }
12659 
kvm_unload_vcpu_mmus(struct kvm * kvm)12660 static void kvm_unload_vcpu_mmus(struct kvm *kvm)
12661 {
12662 	unsigned long i;
12663 	struct kvm_vcpu *vcpu;
12664 
12665 	kvm_for_each_vcpu(i, vcpu, kvm) {
12666 		kvm_clear_async_pf_completion_queue(vcpu);
12667 		kvm_unload_vcpu_mmu(vcpu);
12668 	}
12669 }
12670 
kvm_arch_sync_events(struct kvm * kvm)12671 void kvm_arch_sync_events(struct kvm *kvm)
12672 {
12673 	cancel_delayed_work_sync(&kvm->arch.kvmclock_sync_work);
12674 	cancel_delayed_work_sync(&kvm->arch.kvmclock_update_work);
12675 	kvm_free_pit(kvm);
12676 }
12677 
12678 /**
12679  * __x86_set_memory_region: Setup KVM internal memory slot
12680  *
12681  * @kvm: the kvm pointer to the VM.
12682  * @id: the slot ID to setup.
12683  * @gpa: the GPA to install the slot (unused when @size == 0).
12684  * @size: the size of the slot. Set to zero to uninstall a slot.
12685  *
12686  * This function helps to setup a KVM internal memory slot.  Specify
12687  * @size > 0 to install a new slot, while @size == 0 to uninstall a
12688  * slot.  The return code can be one of the following:
12689  *
12690  *   HVA:           on success (uninstall will return a bogus HVA)
12691  *   -errno:        on error
12692  *
12693  * The caller should always use IS_ERR() to check the return value
12694  * before use.  Note, the KVM internal memory slots are guaranteed to
12695  * remain valid and unchanged until the VM is destroyed, i.e., the
12696  * GPA->HVA translation will not change.  However, the HVA is a user
12697  * address, i.e. its accessibility is not guaranteed, and must be
12698  * accessed via __copy_{to,from}_user().
12699  */
__x86_set_memory_region(struct kvm * kvm,int id,gpa_t gpa,u32 size)12700 void __user * __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa,
12701 				      u32 size)
12702 {
12703 	int i, r;
12704 	unsigned long hva, old_npages;
12705 	struct kvm_memslots *slots = kvm_memslots(kvm);
12706 	struct kvm_memory_slot *slot;
12707 
12708 	/* Called with kvm->slots_lock held.  */
12709 	if (WARN_ON(id >= KVM_MEM_SLOTS_NUM))
12710 		return ERR_PTR_USR(-EINVAL);
12711 
12712 	slot = id_to_memslot(slots, id);
12713 	if (size) {
12714 		if (slot && slot->npages)
12715 			return ERR_PTR_USR(-EEXIST);
12716 
12717 		/*
12718 		 * MAP_SHARED to prevent internal slot pages from being moved
12719 		 * by fork()/COW.
12720 		 */
12721 		hva = vm_mmap(NULL, 0, size, PROT_READ | PROT_WRITE,
12722 			      MAP_SHARED | MAP_ANONYMOUS, 0);
12723 		if (IS_ERR_VALUE(hva))
12724 			return (void __user *)hva;
12725 	} else {
12726 		if (!slot || !slot->npages)
12727 			return NULL;
12728 
12729 		old_npages = slot->npages;
12730 		hva = slot->userspace_addr;
12731 	}
12732 
12733 	for (i = 0; i < kvm_arch_nr_memslot_as_ids(kvm); i++) {
12734 		struct kvm_userspace_memory_region2 m;
12735 
12736 		m.slot = id | (i << 16);
12737 		m.flags = 0;
12738 		m.guest_phys_addr = gpa;
12739 		m.userspace_addr = hva;
12740 		m.memory_size = size;
12741 		r = __kvm_set_memory_region(kvm, &m);
12742 		if (r < 0)
12743 			return ERR_PTR_USR(r);
12744 	}
12745 
12746 	if (!size)
12747 		vm_munmap(hva, old_npages * PAGE_SIZE);
12748 
12749 	return (void __user *)hva;
12750 }
12751 EXPORT_SYMBOL_GPL(__x86_set_memory_region);
12752 
kvm_arch_pre_destroy_vm(struct kvm * kvm)12753 void kvm_arch_pre_destroy_vm(struct kvm *kvm)
12754 {
12755 	kvm_mmu_pre_destroy_vm(kvm);
12756 }
12757 
kvm_arch_destroy_vm(struct kvm * kvm)12758 void kvm_arch_destroy_vm(struct kvm *kvm)
12759 {
12760 	if (current->mm == kvm->mm) {
12761 		/*
12762 		 * Free memory regions allocated on behalf of userspace,
12763 		 * unless the memory map has changed due to process exit
12764 		 * or fd copying.
12765 		 */
12766 		mutex_lock(&kvm->slots_lock);
12767 		__x86_set_memory_region(kvm, APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
12768 					0, 0);
12769 		__x86_set_memory_region(kvm, IDENTITY_PAGETABLE_PRIVATE_MEMSLOT,
12770 					0, 0);
12771 		__x86_set_memory_region(kvm, TSS_PRIVATE_MEMSLOT, 0, 0);
12772 		mutex_unlock(&kvm->slots_lock);
12773 	}
12774 	kvm_unload_vcpu_mmus(kvm);
12775 	static_call_cond(kvm_x86_vm_destroy)(kvm);
12776 	kvm_free_msr_filter(srcu_dereference_check(kvm->arch.msr_filter, &kvm->srcu, 1));
12777 	kvm_pic_destroy(kvm);
12778 	kvm_ioapic_destroy(kvm);
12779 	kvm_destroy_vcpus(kvm);
12780 	kvfree(rcu_dereference_check(kvm->arch.apic_map, 1));
12781 	kfree(srcu_dereference_check(kvm->arch.pmu_event_filter, &kvm->srcu, 1));
12782 	kvm_mmu_uninit_vm(kvm);
12783 	kvm_page_track_cleanup(kvm);
12784 	kvm_xen_destroy_vm(kvm);
12785 	kvm_hv_destroy_vm(kvm);
12786 }
12787 
memslot_rmap_free(struct kvm_memory_slot * slot)12788 static void memslot_rmap_free(struct kvm_memory_slot *slot)
12789 {
12790 	int i;
12791 
12792 	for (i = 0; i < KVM_NR_PAGE_SIZES; ++i) {
12793 		vfree(slot->arch.rmap[i]);
12794 		slot->arch.rmap[i] = NULL;
12795 	}
12796 }
12797 
kvm_arch_free_memslot(struct kvm * kvm,struct kvm_memory_slot * slot)12798 void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)
12799 {
12800 	int i;
12801 
12802 	memslot_rmap_free(slot);
12803 
12804 	for (i = 1; i < KVM_NR_PAGE_SIZES; ++i) {
12805 		vfree(slot->arch.lpage_info[i - 1]);
12806 		slot->arch.lpage_info[i - 1] = NULL;
12807 	}
12808 
12809 	kvm_page_track_free_memslot(slot);
12810 }
12811 
memslot_rmap_alloc(struct kvm_memory_slot * slot,unsigned long npages)12812 int memslot_rmap_alloc(struct kvm_memory_slot *slot, unsigned long npages)
12813 {
12814 	const int sz = sizeof(*slot->arch.rmap[0]);
12815 	int i;
12816 
12817 	for (i = 0; i < KVM_NR_PAGE_SIZES; ++i) {
12818 		int level = i + 1;
12819 		int lpages = __kvm_mmu_slot_lpages(slot, npages, level);
12820 
12821 		if (slot->arch.rmap[i])
12822 			continue;
12823 
12824 		slot->arch.rmap[i] = __vcalloc(lpages, sz, GFP_KERNEL_ACCOUNT);
12825 		if (!slot->arch.rmap[i]) {
12826 			memslot_rmap_free(slot);
12827 			return -ENOMEM;
12828 		}
12829 	}
12830 
12831 	return 0;
12832 }
12833 
kvm_alloc_memslot_metadata(struct kvm * kvm,struct kvm_memory_slot * slot)12834 static int kvm_alloc_memslot_metadata(struct kvm *kvm,
12835 				      struct kvm_memory_slot *slot)
12836 {
12837 	unsigned long npages = slot->npages;
12838 	int i, r;
12839 
12840 	/*
12841 	 * Clear out the previous array pointers for the KVM_MR_MOVE case.  The
12842 	 * old arrays will be freed by __kvm_set_memory_region() if installing
12843 	 * the new memslot is successful.
12844 	 */
12845 	memset(&slot->arch, 0, sizeof(slot->arch));
12846 
12847 	if (kvm_memslots_have_rmaps(kvm)) {
12848 		r = memslot_rmap_alloc(slot, npages);
12849 		if (r)
12850 			return r;
12851 	}
12852 
12853 	for (i = 1; i < KVM_NR_PAGE_SIZES; ++i) {
12854 		struct kvm_lpage_info *linfo;
12855 		unsigned long ugfn;
12856 		int lpages;
12857 		int level = i + 1;
12858 
12859 		lpages = __kvm_mmu_slot_lpages(slot, npages, level);
12860 
12861 		linfo = __vcalloc(lpages, sizeof(*linfo), GFP_KERNEL_ACCOUNT);
12862 		if (!linfo)
12863 			goto out_free;
12864 
12865 		slot->arch.lpage_info[i - 1] = linfo;
12866 
12867 		if (slot->base_gfn & (KVM_PAGES_PER_HPAGE(level) - 1))
12868 			linfo[0].disallow_lpage = 1;
12869 		if ((slot->base_gfn + npages) & (KVM_PAGES_PER_HPAGE(level) - 1))
12870 			linfo[lpages - 1].disallow_lpage = 1;
12871 		ugfn = slot->userspace_addr >> PAGE_SHIFT;
12872 		/*
12873 		 * If the gfn and userspace address are not aligned wrt each
12874 		 * other, disable large page support for this slot.
12875 		 */
12876 		if ((slot->base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1)) {
12877 			unsigned long j;
12878 
12879 			for (j = 0; j < lpages; ++j)
12880 				linfo[j].disallow_lpage = 1;
12881 		}
12882 	}
12883 
12884 #ifdef CONFIG_KVM_GENERIC_MEMORY_ATTRIBUTES
12885 	kvm_mmu_init_memslot_memory_attributes(kvm, slot);
12886 #endif
12887 
12888 	if (kvm_page_track_create_memslot(kvm, slot, npages))
12889 		goto out_free;
12890 
12891 	return 0;
12892 
12893 out_free:
12894 	memslot_rmap_free(slot);
12895 
12896 	for (i = 1; i < KVM_NR_PAGE_SIZES; ++i) {
12897 		vfree(slot->arch.lpage_info[i - 1]);
12898 		slot->arch.lpage_info[i - 1] = NULL;
12899 	}
12900 	return -ENOMEM;
12901 }
12902 
kvm_arch_memslots_updated(struct kvm * kvm,u64 gen)12903 void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen)
12904 {
12905 	struct kvm_vcpu *vcpu;
12906 	unsigned long i;
12907 
12908 	/*
12909 	 * memslots->generation has been incremented.
12910 	 * mmio generation may have reached its maximum value.
12911 	 */
12912 	kvm_mmu_invalidate_mmio_sptes(kvm, gen);
12913 
12914 	/* Force re-initialization of steal_time cache */
12915 	kvm_for_each_vcpu(i, vcpu, kvm)
12916 		kvm_vcpu_kick(vcpu);
12917 }
12918 
kvm_arch_prepare_memory_region(struct kvm * kvm,const struct kvm_memory_slot * old,struct kvm_memory_slot * new,enum kvm_mr_change change)12919 int kvm_arch_prepare_memory_region(struct kvm *kvm,
12920 				   const struct kvm_memory_slot *old,
12921 				   struct kvm_memory_slot *new,
12922 				   enum kvm_mr_change change)
12923 {
12924 	/*
12925 	 * KVM doesn't support moving memslots when there are external page
12926 	 * trackers attached to the VM, i.e. if KVMGT is in use.
12927 	 */
12928 	if (change == KVM_MR_MOVE && kvm_page_track_has_external_user(kvm))
12929 		return -EINVAL;
12930 
12931 	if (change == KVM_MR_CREATE || change == KVM_MR_MOVE) {
12932 		if ((new->base_gfn + new->npages - 1) > kvm_mmu_max_gfn())
12933 			return -EINVAL;
12934 
12935 		return kvm_alloc_memslot_metadata(kvm, new);
12936 	}
12937 
12938 	if (change == KVM_MR_FLAGS_ONLY)
12939 		memcpy(&new->arch, &old->arch, sizeof(old->arch));
12940 	else if (WARN_ON_ONCE(change != KVM_MR_DELETE))
12941 		return -EIO;
12942 
12943 	return 0;
12944 }
12945 
12946 
kvm_mmu_update_cpu_dirty_logging(struct kvm * kvm,bool enable)12947 static void kvm_mmu_update_cpu_dirty_logging(struct kvm *kvm, bool enable)
12948 {
12949 	int nr_slots;
12950 
12951 	if (!kvm_x86_ops.cpu_dirty_log_size)
12952 		return;
12953 
12954 	nr_slots = atomic_read(&kvm->nr_memslots_dirty_logging);
12955 	if ((enable && nr_slots == 1) || !nr_slots)
12956 		kvm_make_all_cpus_request(kvm, KVM_REQ_UPDATE_CPU_DIRTY_LOGGING);
12957 }
12958 
kvm_mmu_slot_apply_flags(struct kvm * kvm,struct kvm_memory_slot * old,const struct kvm_memory_slot * new,enum kvm_mr_change change)12959 static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
12960 				     struct kvm_memory_slot *old,
12961 				     const struct kvm_memory_slot *new,
12962 				     enum kvm_mr_change change)
12963 {
12964 	u32 old_flags = old ? old->flags : 0;
12965 	u32 new_flags = new ? new->flags : 0;
12966 	bool log_dirty_pages = new_flags & KVM_MEM_LOG_DIRTY_PAGES;
12967 
12968 	/*
12969 	 * Update CPU dirty logging if dirty logging is being toggled.  This
12970 	 * applies to all operations.
12971 	 */
12972 	if ((old_flags ^ new_flags) & KVM_MEM_LOG_DIRTY_PAGES)
12973 		kvm_mmu_update_cpu_dirty_logging(kvm, log_dirty_pages);
12974 
12975 	/*
12976 	 * Nothing more to do for RO slots (which can't be dirtied and can't be
12977 	 * made writable) or CREATE/MOVE/DELETE of a slot.
12978 	 *
12979 	 * For a memslot with dirty logging disabled:
12980 	 * CREATE:      No dirty mappings will already exist.
12981 	 * MOVE/DELETE: The old mappings will already have been cleaned up by
12982 	 *		kvm_arch_flush_shadow_memslot()
12983 	 *
12984 	 * For a memslot with dirty logging enabled:
12985 	 * CREATE:      No shadow pages exist, thus nothing to write-protect
12986 	 *		and no dirty bits to clear.
12987 	 * MOVE/DELETE: The old mappings will already have been cleaned up by
12988 	 *		kvm_arch_flush_shadow_memslot().
12989 	 */
12990 	if ((change != KVM_MR_FLAGS_ONLY) || (new_flags & KVM_MEM_READONLY))
12991 		return;
12992 
12993 	/*
12994 	 * READONLY and non-flags changes were filtered out above, and the only
12995 	 * other flag is LOG_DIRTY_PAGES, i.e. something is wrong if dirty
12996 	 * logging isn't being toggled on or off.
12997 	 */
12998 	if (WARN_ON_ONCE(!((old_flags ^ new_flags) & KVM_MEM_LOG_DIRTY_PAGES)))
12999 		return;
13000 
13001 	if (!log_dirty_pages) {
13002 		/*
13003 		 * Dirty logging tracks sptes in 4k granularity, meaning that
13004 		 * large sptes have to be split.  If live migration succeeds,
13005 		 * the guest in the source machine will be destroyed and large
13006 		 * sptes will be created in the destination.  However, if the
13007 		 * guest continues to run in the source machine (for example if
13008 		 * live migration fails), small sptes will remain around and
13009 		 * cause bad performance.
13010 		 *
13011 		 * Scan sptes if dirty logging has been stopped, dropping those
13012 		 * which can be collapsed into a single large-page spte.  Later
13013 		 * page faults will create the large-page sptes.
13014 		 */
13015 		kvm_mmu_zap_collapsible_sptes(kvm, new);
13016 	} else {
13017 		/*
13018 		 * Initially-all-set does not require write protecting any page,
13019 		 * because they're all assumed to be dirty.
13020 		 */
13021 		if (kvm_dirty_log_manual_protect_and_init_set(kvm))
13022 			return;
13023 
13024 		if (READ_ONCE(eager_page_split))
13025 			kvm_mmu_slot_try_split_huge_pages(kvm, new, PG_LEVEL_4K);
13026 
13027 		if (kvm_x86_ops.cpu_dirty_log_size) {
13028 			kvm_mmu_slot_leaf_clear_dirty(kvm, new);
13029 			kvm_mmu_slot_remove_write_access(kvm, new, PG_LEVEL_2M);
13030 		} else {
13031 			kvm_mmu_slot_remove_write_access(kvm, new, PG_LEVEL_4K);
13032 		}
13033 
13034 		/*
13035 		 * Unconditionally flush the TLBs after enabling dirty logging.
13036 		 * A flush is almost always going to be necessary (see below),
13037 		 * and unconditionally flushing allows the helpers to omit
13038 		 * the subtly complex checks when removing write access.
13039 		 *
13040 		 * Do the flush outside of mmu_lock to reduce the amount of
13041 		 * time mmu_lock is held.  Flushing after dropping mmu_lock is
13042 		 * safe as KVM only needs to guarantee the slot is fully
13043 		 * write-protected before returning to userspace, i.e. before
13044 		 * userspace can consume the dirty status.
13045 		 *
13046 		 * Flushing outside of mmu_lock requires KVM to be careful when
13047 		 * making decisions based on writable status of an SPTE, e.g. a
13048 		 * !writable SPTE doesn't guarantee a CPU can't perform writes.
13049 		 *
13050 		 * Specifically, KVM also write-protects guest page tables to
13051 		 * monitor changes when using shadow paging, and must guarantee
13052 		 * no CPUs can write to those page before mmu_lock is dropped.
13053 		 * Because CPUs may have stale TLB entries at this point, a
13054 		 * !writable SPTE doesn't guarantee CPUs can't perform writes.
13055 		 *
13056 		 * KVM also allows making SPTES writable outside of mmu_lock,
13057 		 * e.g. to allow dirty logging without taking mmu_lock.
13058 		 *
13059 		 * To handle these scenarios, KVM uses a separate software-only
13060 		 * bit (MMU-writable) to track if a SPTE is !writable due to
13061 		 * a guest page table being write-protected (KVM clears the
13062 		 * MMU-writable flag when write-protecting for shadow paging).
13063 		 *
13064 		 * The use of MMU-writable is also the primary motivation for
13065 		 * the unconditional flush.  Because KVM must guarantee that a
13066 		 * CPU doesn't contain stale, writable TLB entries for a
13067 		 * !MMU-writable SPTE, KVM must flush if it encounters any
13068 		 * MMU-writable SPTE regardless of whether the actual hardware
13069 		 * writable bit was set.  I.e. KVM is almost guaranteed to need
13070 		 * to flush, while unconditionally flushing allows the "remove
13071 		 * write access" helpers to ignore MMU-writable entirely.
13072 		 *
13073 		 * See is_writable_pte() for more details (the case involving
13074 		 * access-tracked SPTEs is particularly relevant).
13075 		 */
13076 		kvm_flush_remote_tlbs_memslot(kvm, new);
13077 	}
13078 }
13079 
kvm_arch_commit_memory_region(struct kvm * kvm,struct kvm_memory_slot * old,const struct kvm_memory_slot * new,enum kvm_mr_change change)13080 void kvm_arch_commit_memory_region(struct kvm *kvm,
13081 				struct kvm_memory_slot *old,
13082 				const struct kvm_memory_slot *new,
13083 				enum kvm_mr_change change)
13084 {
13085 	if (change == KVM_MR_DELETE)
13086 		kvm_page_track_delete_slot(kvm, old);
13087 
13088 	if (!kvm->arch.n_requested_mmu_pages &&
13089 	    (change == KVM_MR_CREATE || change == KVM_MR_DELETE)) {
13090 		unsigned long nr_mmu_pages;
13091 
13092 		nr_mmu_pages = kvm->nr_memslot_pages / KVM_MEMSLOT_PAGES_TO_MMU_PAGES_RATIO;
13093 		nr_mmu_pages = max(nr_mmu_pages, KVM_MIN_ALLOC_MMU_PAGES);
13094 		kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages);
13095 	}
13096 
13097 	kvm_mmu_slot_apply_flags(kvm, old, new, change);
13098 
13099 	/* Free the arrays associated with the old memslot. */
13100 	if (change == KVM_MR_MOVE)
13101 		kvm_arch_free_memslot(kvm, old);
13102 }
13103 
kvm_guest_apic_has_interrupt(struct kvm_vcpu * vcpu)13104 static inline bool kvm_guest_apic_has_interrupt(struct kvm_vcpu *vcpu)
13105 {
13106 	return (is_guest_mode(vcpu) &&
13107 		static_call(kvm_x86_guest_apic_has_interrupt)(vcpu));
13108 }
13109 
kvm_vcpu_has_events(struct kvm_vcpu * vcpu)13110 static inline bool kvm_vcpu_has_events(struct kvm_vcpu *vcpu)
13111 {
13112 	if (!list_empty_careful(&vcpu->async_pf.done))
13113 		return true;
13114 
13115 	if (kvm_apic_has_pending_init_or_sipi(vcpu) &&
13116 	    kvm_apic_init_sipi_allowed(vcpu))
13117 		return true;
13118 
13119 	if (vcpu->arch.pv.pv_unhalted)
13120 		return true;
13121 
13122 	if (kvm_is_exception_pending(vcpu))
13123 		return true;
13124 
13125 	if (kvm_test_request(KVM_REQ_NMI, vcpu) ||
13126 	    (vcpu->arch.nmi_pending &&
13127 	     static_call(kvm_x86_nmi_allowed)(vcpu, false)))
13128 		return true;
13129 
13130 #ifdef CONFIG_KVM_SMM
13131 	if (kvm_test_request(KVM_REQ_SMI, vcpu) ||
13132 	    (vcpu->arch.smi_pending &&
13133 	     static_call(kvm_x86_smi_allowed)(vcpu, false)))
13134 		return true;
13135 #endif
13136 
13137 	if (kvm_test_request(KVM_REQ_PMI, vcpu))
13138 		return true;
13139 
13140 	if (kvm_arch_interrupt_allowed(vcpu) &&
13141 	    (kvm_cpu_has_interrupt(vcpu) ||
13142 	    kvm_guest_apic_has_interrupt(vcpu)))
13143 		return true;
13144 
13145 	if (kvm_hv_has_stimer_pending(vcpu))
13146 		return true;
13147 
13148 	if (is_guest_mode(vcpu) &&
13149 	    kvm_x86_ops.nested_ops->has_events &&
13150 	    kvm_x86_ops.nested_ops->has_events(vcpu))
13151 		return true;
13152 
13153 	if (kvm_xen_has_pending_events(vcpu))
13154 		return true;
13155 
13156 	return false;
13157 }
13158 
kvm_arch_vcpu_runnable(struct kvm_vcpu * vcpu)13159 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
13160 {
13161 	return kvm_vcpu_running(vcpu) || kvm_vcpu_has_events(vcpu);
13162 }
13163 
kvm_arch_dy_has_pending_interrupt(struct kvm_vcpu * vcpu)13164 bool kvm_arch_dy_has_pending_interrupt(struct kvm_vcpu *vcpu)
13165 {
13166 	return kvm_vcpu_apicv_active(vcpu) &&
13167 	       static_call(kvm_x86_dy_apicv_has_pending_interrupt)(vcpu);
13168 }
13169 
kvm_arch_vcpu_preempted_in_kernel(struct kvm_vcpu * vcpu)13170 bool kvm_arch_vcpu_preempted_in_kernel(struct kvm_vcpu *vcpu)
13171 {
13172 	return vcpu->arch.preempted_in_kernel;
13173 }
13174 
kvm_arch_dy_runnable(struct kvm_vcpu * vcpu)13175 bool kvm_arch_dy_runnable(struct kvm_vcpu *vcpu)
13176 {
13177 	if (READ_ONCE(vcpu->arch.pv.pv_unhalted))
13178 		return true;
13179 
13180 	if (kvm_test_request(KVM_REQ_NMI, vcpu) ||
13181 #ifdef CONFIG_KVM_SMM
13182 		kvm_test_request(KVM_REQ_SMI, vcpu) ||
13183 #endif
13184 		 kvm_test_request(KVM_REQ_EVENT, vcpu))
13185 		return true;
13186 
13187 	return kvm_arch_dy_has_pending_interrupt(vcpu);
13188 }
13189 
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)13190 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
13191 {
13192 	if (vcpu->arch.guest_state_protected)
13193 		return true;
13194 
13195 	return static_call(kvm_x86_get_cpl)(vcpu) == 0;
13196 }
13197 
kvm_arch_vcpu_get_ip(struct kvm_vcpu * vcpu)13198 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
13199 {
13200 	return kvm_rip_read(vcpu);
13201 }
13202 
kvm_arch_vcpu_should_kick(struct kvm_vcpu * vcpu)13203 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
13204 {
13205 	return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
13206 }
13207 
kvm_arch_interrupt_allowed(struct kvm_vcpu * vcpu)13208 int kvm_arch_interrupt_allowed(struct kvm_vcpu *vcpu)
13209 {
13210 	return static_call(kvm_x86_interrupt_allowed)(vcpu, false);
13211 }
13212 
kvm_get_linear_rip(struct kvm_vcpu * vcpu)13213 unsigned long kvm_get_linear_rip(struct kvm_vcpu *vcpu)
13214 {
13215 	/* Can't read the RIP when guest state is protected, just return 0 */
13216 	if (vcpu->arch.guest_state_protected)
13217 		return 0;
13218 
13219 	if (is_64_bit_mode(vcpu))
13220 		return kvm_rip_read(vcpu);
13221 	return (u32)(get_segment_base(vcpu, VCPU_SREG_CS) +
13222 		     kvm_rip_read(vcpu));
13223 }
13224 EXPORT_SYMBOL_GPL(kvm_get_linear_rip);
13225 
kvm_is_linear_rip(struct kvm_vcpu * vcpu,unsigned long linear_rip)13226 bool kvm_is_linear_rip(struct kvm_vcpu *vcpu, unsigned long linear_rip)
13227 {
13228 	return kvm_get_linear_rip(vcpu) == linear_rip;
13229 }
13230 EXPORT_SYMBOL_GPL(kvm_is_linear_rip);
13231 
kvm_get_rflags(struct kvm_vcpu * vcpu)13232 unsigned long kvm_get_rflags(struct kvm_vcpu *vcpu)
13233 {
13234 	unsigned long rflags;
13235 
13236 	rflags = static_call(kvm_x86_get_rflags)(vcpu);
13237 	if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
13238 		rflags &= ~X86_EFLAGS_TF;
13239 	return rflags;
13240 }
13241 EXPORT_SYMBOL_GPL(kvm_get_rflags);
13242 
__kvm_set_rflags(struct kvm_vcpu * vcpu,unsigned long rflags)13243 static void __kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
13244 {
13245 	if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP &&
13246 	    kvm_is_linear_rip(vcpu, vcpu->arch.singlestep_rip))
13247 		rflags |= X86_EFLAGS_TF;
13248 	static_call(kvm_x86_set_rflags)(vcpu, rflags);
13249 }
13250 
kvm_set_rflags(struct kvm_vcpu * vcpu,unsigned long rflags)13251 void kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
13252 {
13253 	__kvm_set_rflags(vcpu, rflags);
13254 	kvm_make_request(KVM_REQ_EVENT, vcpu);
13255 }
13256 EXPORT_SYMBOL_GPL(kvm_set_rflags);
13257 
kvm_async_pf_hash_fn(gfn_t gfn)13258 static inline u32 kvm_async_pf_hash_fn(gfn_t gfn)
13259 {
13260 	BUILD_BUG_ON(!is_power_of_2(ASYNC_PF_PER_VCPU));
13261 
13262 	return hash_32(gfn & 0xffffffff, order_base_2(ASYNC_PF_PER_VCPU));
13263 }
13264 
kvm_async_pf_next_probe(u32 key)13265 static inline u32 kvm_async_pf_next_probe(u32 key)
13266 {
13267 	return (key + 1) & (ASYNC_PF_PER_VCPU - 1);
13268 }
13269 
kvm_add_async_pf_gfn(struct kvm_vcpu * vcpu,gfn_t gfn)13270 static void kvm_add_async_pf_gfn(struct kvm_vcpu *vcpu, gfn_t gfn)
13271 {
13272 	u32 key = kvm_async_pf_hash_fn(gfn);
13273 
13274 	while (vcpu->arch.apf.gfns[key] != ~0)
13275 		key = kvm_async_pf_next_probe(key);
13276 
13277 	vcpu->arch.apf.gfns[key] = gfn;
13278 }
13279 
kvm_async_pf_gfn_slot(struct kvm_vcpu * vcpu,gfn_t gfn)13280 static u32 kvm_async_pf_gfn_slot(struct kvm_vcpu *vcpu, gfn_t gfn)
13281 {
13282 	int i;
13283 	u32 key = kvm_async_pf_hash_fn(gfn);
13284 
13285 	for (i = 0; i < ASYNC_PF_PER_VCPU &&
13286 		     (vcpu->arch.apf.gfns[key] != gfn &&
13287 		      vcpu->arch.apf.gfns[key] != ~0); i++)
13288 		key = kvm_async_pf_next_probe(key);
13289 
13290 	return key;
13291 }
13292 
kvm_find_async_pf_gfn(struct kvm_vcpu * vcpu,gfn_t gfn)13293 bool kvm_find_async_pf_gfn(struct kvm_vcpu *vcpu, gfn_t gfn)
13294 {
13295 	return vcpu->arch.apf.gfns[kvm_async_pf_gfn_slot(vcpu, gfn)] == gfn;
13296 }
13297 
kvm_del_async_pf_gfn(struct kvm_vcpu * vcpu,gfn_t gfn)13298 static void kvm_del_async_pf_gfn(struct kvm_vcpu *vcpu, gfn_t gfn)
13299 {
13300 	u32 i, j, k;
13301 
13302 	i = j = kvm_async_pf_gfn_slot(vcpu, gfn);
13303 
13304 	if (WARN_ON_ONCE(vcpu->arch.apf.gfns[i] != gfn))
13305 		return;
13306 
13307 	while (true) {
13308 		vcpu->arch.apf.gfns[i] = ~0;
13309 		do {
13310 			j = kvm_async_pf_next_probe(j);
13311 			if (vcpu->arch.apf.gfns[j] == ~0)
13312 				return;
13313 			k = kvm_async_pf_hash_fn(vcpu->arch.apf.gfns[j]);
13314 			/*
13315 			 * k lies cyclically in ]i,j]
13316 			 * |    i.k.j |
13317 			 * |....j i.k.| or  |.k..j i...|
13318 			 */
13319 		} while ((i <= j) ? (i < k && k <= j) : (i < k || k <= j));
13320 		vcpu->arch.apf.gfns[i] = vcpu->arch.apf.gfns[j];
13321 		i = j;
13322 	}
13323 }
13324 
apf_put_user_notpresent(struct kvm_vcpu * vcpu)13325 static inline int apf_put_user_notpresent(struct kvm_vcpu *vcpu)
13326 {
13327 	u32 reason = KVM_PV_REASON_PAGE_NOT_PRESENT;
13328 
13329 	return kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.apf.data, &reason,
13330 				      sizeof(reason));
13331 }
13332 
apf_put_user_ready(struct kvm_vcpu * vcpu,u32 token)13333 static inline int apf_put_user_ready(struct kvm_vcpu *vcpu, u32 token)
13334 {
13335 	unsigned int offset = offsetof(struct kvm_vcpu_pv_apf_data, token);
13336 
13337 	return kvm_write_guest_offset_cached(vcpu->kvm, &vcpu->arch.apf.data,
13338 					     &token, offset, sizeof(token));
13339 }
13340 
apf_pageready_slot_free(struct kvm_vcpu * vcpu)13341 static inline bool apf_pageready_slot_free(struct kvm_vcpu *vcpu)
13342 {
13343 	unsigned int offset = offsetof(struct kvm_vcpu_pv_apf_data, token);
13344 	u32 val;
13345 
13346 	if (kvm_read_guest_offset_cached(vcpu->kvm, &vcpu->arch.apf.data,
13347 					 &val, offset, sizeof(val)))
13348 		return false;
13349 
13350 	return !val;
13351 }
13352 
kvm_can_deliver_async_pf(struct kvm_vcpu * vcpu)13353 static bool kvm_can_deliver_async_pf(struct kvm_vcpu *vcpu)
13354 {
13355 
13356 	if (!kvm_pv_async_pf_enabled(vcpu))
13357 		return false;
13358 
13359 	if (vcpu->arch.apf.send_user_only &&
13360 	    static_call(kvm_x86_get_cpl)(vcpu) == 0)
13361 		return false;
13362 
13363 	if (is_guest_mode(vcpu)) {
13364 		/*
13365 		 * L1 needs to opt into the special #PF vmexits that are
13366 		 * used to deliver async page faults.
13367 		 */
13368 		return vcpu->arch.apf.delivery_as_pf_vmexit;
13369 	} else {
13370 		/*
13371 		 * Play it safe in case the guest temporarily disables paging.
13372 		 * The real mode IDT in particular is unlikely to have a #PF
13373 		 * exception setup.
13374 		 */
13375 		return is_paging(vcpu);
13376 	}
13377 }
13378 
kvm_can_do_async_pf(struct kvm_vcpu * vcpu)13379 bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu)
13380 {
13381 	if (unlikely(!lapic_in_kernel(vcpu) ||
13382 		     kvm_event_needs_reinjection(vcpu) ||
13383 		     kvm_is_exception_pending(vcpu)))
13384 		return false;
13385 
13386 	if (kvm_hlt_in_guest(vcpu->kvm) && !kvm_can_deliver_async_pf(vcpu))
13387 		return false;
13388 
13389 	/*
13390 	 * If interrupts are off we cannot even use an artificial
13391 	 * halt state.
13392 	 */
13393 	return kvm_arch_interrupt_allowed(vcpu);
13394 }
13395 
kvm_arch_async_page_not_present(struct kvm_vcpu * vcpu,struct kvm_async_pf * work)13396 bool kvm_arch_async_page_not_present(struct kvm_vcpu *vcpu,
13397 				     struct kvm_async_pf *work)
13398 {
13399 	struct x86_exception fault;
13400 
13401 	trace_kvm_async_pf_not_present(work->arch.token, work->cr2_or_gpa);
13402 	kvm_add_async_pf_gfn(vcpu, work->arch.gfn);
13403 
13404 	if (kvm_can_deliver_async_pf(vcpu) &&
13405 	    !apf_put_user_notpresent(vcpu)) {
13406 		fault.vector = PF_VECTOR;
13407 		fault.error_code_valid = true;
13408 		fault.error_code = 0;
13409 		fault.nested_page_fault = false;
13410 		fault.address = work->arch.token;
13411 		fault.async_page_fault = true;
13412 		kvm_inject_page_fault(vcpu, &fault);
13413 		return true;
13414 	} else {
13415 		/*
13416 		 * It is not possible to deliver a paravirtualized asynchronous
13417 		 * page fault, but putting the guest in an artificial halt state
13418 		 * can be beneficial nevertheless: if an interrupt arrives, we
13419 		 * can deliver it timely and perhaps the guest will schedule
13420 		 * another process.  When the instruction that triggered a page
13421 		 * fault is retried, hopefully the page will be ready in the host.
13422 		 */
13423 		kvm_make_request(KVM_REQ_APF_HALT, vcpu);
13424 		return false;
13425 	}
13426 }
13427 
kvm_arch_async_page_present(struct kvm_vcpu * vcpu,struct kvm_async_pf * work)13428 void kvm_arch_async_page_present(struct kvm_vcpu *vcpu,
13429 				 struct kvm_async_pf *work)
13430 {
13431 	struct kvm_lapic_irq irq = {
13432 		.delivery_mode = APIC_DM_FIXED,
13433 		.vector = vcpu->arch.apf.vec
13434 	};
13435 
13436 	if (work->wakeup_all)
13437 		work->arch.token = ~0; /* broadcast wakeup */
13438 	else
13439 		kvm_del_async_pf_gfn(vcpu, work->arch.gfn);
13440 	trace_kvm_async_pf_ready(work->arch.token, work->cr2_or_gpa);
13441 
13442 	if ((work->wakeup_all || work->notpresent_injected) &&
13443 	    kvm_pv_async_pf_enabled(vcpu) &&
13444 	    !apf_put_user_ready(vcpu, work->arch.token)) {
13445 		vcpu->arch.apf.pageready_pending = true;
13446 		kvm_apic_set_irq(vcpu, &irq, NULL);
13447 	}
13448 
13449 	vcpu->arch.apf.halted = false;
13450 	vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
13451 }
13452 
kvm_arch_async_page_present_queued(struct kvm_vcpu * vcpu)13453 void kvm_arch_async_page_present_queued(struct kvm_vcpu *vcpu)
13454 {
13455 	kvm_make_request(KVM_REQ_APF_READY, vcpu);
13456 	if (!vcpu->arch.apf.pageready_pending)
13457 		kvm_vcpu_kick(vcpu);
13458 }
13459 
kvm_arch_can_dequeue_async_page_present(struct kvm_vcpu * vcpu)13460 bool kvm_arch_can_dequeue_async_page_present(struct kvm_vcpu *vcpu)
13461 {
13462 	if (!kvm_pv_async_pf_enabled(vcpu))
13463 		return true;
13464 	else
13465 		return kvm_lapic_enabled(vcpu) && apf_pageready_slot_free(vcpu);
13466 }
13467 
kvm_arch_start_assignment(struct kvm * kvm)13468 void kvm_arch_start_assignment(struct kvm *kvm)
13469 {
13470 	if (atomic_inc_return(&kvm->arch.assigned_device_count) == 1)
13471 		static_call_cond(kvm_x86_pi_start_assignment)(kvm);
13472 }
13473 EXPORT_SYMBOL_GPL(kvm_arch_start_assignment);
13474 
kvm_arch_end_assignment(struct kvm * kvm)13475 void kvm_arch_end_assignment(struct kvm *kvm)
13476 {
13477 	atomic_dec(&kvm->arch.assigned_device_count);
13478 }
13479 EXPORT_SYMBOL_GPL(kvm_arch_end_assignment);
13480 
kvm_arch_has_assigned_device(struct kvm * kvm)13481 bool noinstr kvm_arch_has_assigned_device(struct kvm *kvm)
13482 {
13483 	return raw_atomic_read(&kvm->arch.assigned_device_count);
13484 }
13485 EXPORT_SYMBOL_GPL(kvm_arch_has_assigned_device);
13486 
kvm_noncoherent_dma_assignment_start_or_stop(struct kvm * kvm)13487 static void kvm_noncoherent_dma_assignment_start_or_stop(struct kvm *kvm)
13488 {
13489 	/*
13490 	 * Non-coherent DMA assignment and de-assignment will affect
13491 	 * whether KVM honors guest MTRRs and cause changes in memtypes
13492 	 * in TDP.
13493 	 * So, pass %true unconditionally to indicate non-coherent DMA was,
13494 	 * or will be involved, and that zapping SPTEs might be necessary.
13495 	 */
13496 	if (__kvm_mmu_honors_guest_mtrrs(true))
13497 		kvm_zap_gfn_range(kvm, gpa_to_gfn(0), gpa_to_gfn(~0ULL));
13498 }
13499 
kvm_arch_register_noncoherent_dma(struct kvm * kvm)13500 void kvm_arch_register_noncoherent_dma(struct kvm *kvm)
13501 {
13502 	if (atomic_inc_return(&kvm->arch.noncoherent_dma_count) == 1)
13503 		kvm_noncoherent_dma_assignment_start_or_stop(kvm);
13504 }
13505 EXPORT_SYMBOL_GPL(kvm_arch_register_noncoherent_dma);
13506 
kvm_arch_unregister_noncoherent_dma(struct kvm * kvm)13507 void kvm_arch_unregister_noncoherent_dma(struct kvm *kvm)
13508 {
13509 	if (!atomic_dec_return(&kvm->arch.noncoherent_dma_count))
13510 		kvm_noncoherent_dma_assignment_start_or_stop(kvm);
13511 }
13512 EXPORT_SYMBOL_GPL(kvm_arch_unregister_noncoherent_dma);
13513 
kvm_arch_has_noncoherent_dma(struct kvm * kvm)13514 bool kvm_arch_has_noncoherent_dma(struct kvm *kvm)
13515 {
13516 	return atomic_read(&kvm->arch.noncoherent_dma_count);
13517 }
13518 EXPORT_SYMBOL_GPL(kvm_arch_has_noncoherent_dma);
13519 
kvm_arch_has_irq_bypass(void)13520 bool kvm_arch_has_irq_bypass(void)
13521 {
13522 	return enable_apicv && irq_remapping_cap(IRQ_POSTING_CAP);
13523 }
13524 
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)13525 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
13526 				      struct irq_bypass_producer *prod)
13527 {
13528 	struct kvm_kernel_irqfd *irqfd =
13529 		container_of(cons, struct kvm_kernel_irqfd, consumer);
13530 	int ret;
13531 
13532 	irqfd->producer = prod;
13533 	kvm_arch_start_assignment(irqfd->kvm);
13534 	ret = static_call(kvm_x86_pi_update_irte)(irqfd->kvm,
13535 					 prod->irq, irqfd->gsi, 1);
13536 
13537 	if (ret)
13538 		kvm_arch_end_assignment(irqfd->kvm);
13539 
13540 	return ret;
13541 }
13542 
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)13543 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
13544 				      struct irq_bypass_producer *prod)
13545 {
13546 	int ret;
13547 	struct kvm_kernel_irqfd *irqfd =
13548 		container_of(cons, struct kvm_kernel_irqfd, consumer);
13549 
13550 	WARN_ON(irqfd->producer != prod);
13551 	irqfd->producer = NULL;
13552 
13553 	/*
13554 	 * When producer of consumer is unregistered, we change back to
13555 	 * remapped mode, so we can re-use the current implementation
13556 	 * when the irq is masked/disabled or the consumer side (KVM
13557 	 * int this case doesn't want to receive the interrupts.
13558 	*/
13559 	ret = static_call(kvm_x86_pi_update_irte)(irqfd->kvm, prod->irq, irqfd->gsi, 0);
13560 	if (ret)
13561 		printk(KERN_INFO "irq bypass consumer (token %p) unregistration"
13562 		       " fails: %d\n", irqfd->consumer.token, ret);
13563 
13564 	kvm_arch_end_assignment(irqfd->kvm);
13565 }
13566 
kvm_arch_update_irqfd_routing(struct kvm * kvm,unsigned int host_irq,uint32_t guest_irq,bool set)13567 int kvm_arch_update_irqfd_routing(struct kvm *kvm, unsigned int host_irq,
13568 				   uint32_t guest_irq, bool set)
13569 {
13570 	return static_call(kvm_x86_pi_update_irte)(kvm, host_irq, guest_irq, set);
13571 }
13572 
kvm_arch_irqfd_route_changed(struct kvm_kernel_irq_routing_entry * old,struct kvm_kernel_irq_routing_entry * new)13573 bool kvm_arch_irqfd_route_changed(struct kvm_kernel_irq_routing_entry *old,
13574 				  struct kvm_kernel_irq_routing_entry *new)
13575 {
13576 	if (new->type != KVM_IRQ_ROUTING_MSI)
13577 		return true;
13578 
13579 	return !!memcmp(&old->msi, &new->msi, sizeof(new->msi));
13580 }
13581 
kvm_vector_hashing_enabled(void)13582 bool kvm_vector_hashing_enabled(void)
13583 {
13584 	return vector_hashing;
13585 }
13586 
kvm_arch_no_poll(struct kvm_vcpu * vcpu)13587 bool kvm_arch_no_poll(struct kvm_vcpu *vcpu)
13588 {
13589 	return (vcpu->arch.msr_kvm_poll_control & 1) == 0;
13590 }
13591 EXPORT_SYMBOL_GPL(kvm_arch_no_poll);
13592 
13593 
kvm_spec_ctrl_test_value(u64 value)13594 int kvm_spec_ctrl_test_value(u64 value)
13595 {
13596 	/*
13597 	 * test that setting IA32_SPEC_CTRL to given value
13598 	 * is allowed by the host processor
13599 	 */
13600 
13601 	u64 saved_value;
13602 	unsigned long flags;
13603 	int ret = 0;
13604 
13605 	local_irq_save(flags);
13606 
13607 	if (rdmsrl_safe(MSR_IA32_SPEC_CTRL, &saved_value))
13608 		ret = 1;
13609 	else if (wrmsrl_safe(MSR_IA32_SPEC_CTRL, value))
13610 		ret = 1;
13611 	else
13612 		wrmsrl(MSR_IA32_SPEC_CTRL, saved_value);
13613 
13614 	local_irq_restore(flags);
13615 
13616 	return ret;
13617 }
13618 EXPORT_SYMBOL_GPL(kvm_spec_ctrl_test_value);
13619 
kvm_fixup_and_inject_pf_error(struct kvm_vcpu * vcpu,gva_t gva,u16 error_code)13620 void kvm_fixup_and_inject_pf_error(struct kvm_vcpu *vcpu, gva_t gva, u16 error_code)
13621 {
13622 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
13623 	struct x86_exception fault;
13624 	u64 access = error_code &
13625 		(PFERR_WRITE_MASK | PFERR_FETCH_MASK | PFERR_USER_MASK);
13626 
13627 	if (!(error_code & PFERR_PRESENT_MASK) ||
13628 	    mmu->gva_to_gpa(vcpu, mmu, gva, access, &fault) != INVALID_GPA) {
13629 		/*
13630 		 * If vcpu->arch.walk_mmu->gva_to_gpa succeeded, the page
13631 		 * tables probably do not match the TLB.  Just proceed
13632 		 * with the error code that the processor gave.
13633 		 */
13634 		fault.vector = PF_VECTOR;
13635 		fault.error_code_valid = true;
13636 		fault.error_code = error_code;
13637 		fault.nested_page_fault = false;
13638 		fault.address = gva;
13639 		fault.async_page_fault = false;
13640 	}
13641 	vcpu->arch.walk_mmu->inject_page_fault(vcpu, &fault);
13642 }
13643 EXPORT_SYMBOL_GPL(kvm_fixup_and_inject_pf_error);
13644 
13645 /*
13646  * Handles kvm_read/write_guest_virt*() result and either injects #PF or returns
13647  * KVM_EXIT_INTERNAL_ERROR for cases not currently handled by KVM. Return value
13648  * indicates whether exit to userspace is needed.
13649  */
kvm_handle_memory_failure(struct kvm_vcpu * vcpu,int r,struct x86_exception * e)13650 int kvm_handle_memory_failure(struct kvm_vcpu *vcpu, int r,
13651 			      struct x86_exception *e)
13652 {
13653 	if (r == X86EMUL_PROPAGATE_FAULT) {
13654 		if (KVM_BUG_ON(!e, vcpu->kvm))
13655 			return -EIO;
13656 
13657 		kvm_inject_emulated_page_fault(vcpu, e);
13658 		return 1;
13659 	}
13660 
13661 	/*
13662 	 * In case kvm_read/write_guest_virt*() failed with X86EMUL_IO_NEEDED
13663 	 * while handling a VMX instruction KVM could've handled the request
13664 	 * correctly by exiting to userspace and performing I/O but there
13665 	 * doesn't seem to be a real use-case behind such requests, just return
13666 	 * KVM_EXIT_INTERNAL_ERROR for now.
13667 	 */
13668 	kvm_prepare_emulation_failure_exit(vcpu);
13669 
13670 	return 0;
13671 }
13672 EXPORT_SYMBOL_GPL(kvm_handle_memory_failure);
13673 
kvm_handle_invpcid(struct kvm_vcpu * vcpu,unsigned long type,gva_t gva)13674 int kvm_handle_invpcid(struct kvm_vcpu *vcpu, unsigned long type, gva_t gva)
13675 {
13676 	bool pcid_enabled;
13677 	struct x86_exception e;
13678 	struct {
13679 		u64 pcid;
13680 		u64 gla;
13681 	} operand;
13682 	int r;
13683 
13684 	r = kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e);
13685 	if (r != X86EMUL_CONTINUE)
13686 		return kvm_handle_memory_failure(vcpu, r, &e);
13687 
13688 	if (operand.pcid >> 12 != 0) {
13689 		kvm_inject_gp(vcpu, 0);
13690 		return 1;
13691 	}
13692 
13693 	pcid_enabled = kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE);
13694 
13695 	switch (type) {
13696 	case INVPCID_TYPE_INDIV_ADDR:
13697 		/*
13698 		 * LAM doesn't apply to addresses that are inputs to TLB
13699 		 * invalidation.
13700 		 */
13701 		if ((!pcid_enabled && (operand.pcid != 0)) ||
13702 		    is_noncanonical_address(operand.gla, vcpu)) {
13703 			kvm_inject_gp(vcpu, 0);
13704 			return 1;
13705 		}
13706 		kvm_mmu_invpcid_gva(vcpu, operand.gla, operand.pcid);
13707 		return kvm_skip_emulated_instruction(vcpu);
13708 
13709 	case INVPCID_TYPE_SINGLE_CTXT:
13710 		if (!pcid_enabled && (operand.pcid != 0)) {
13711 			kvm_inject_gp(vcpu, 0);
13712 			return 1;
13713 		}
13714 
13715 		kvm_invalidate_pcid(vcpu, operand.pcid);
13716 		return kvm_skip_emulated_instruction(vcpu);
13717 
13718 	case INVPCID_TYPE_ALL_NON_GLOBAL:
13719 		/*
13720 		 * Currently, KVM doesn't mark global entries in the shadow
13721 		 * page tables, so a non-global flush just degenerates to a
13722 		 * global flush. If needed, we could optimize this later by
13723 		 * keeping track of global entries in shadow page tables.
13724 		 */
13725 
13726 		fallthrough;
13727 	case INVPCID_TYPE_ALL_INCL_GLOBAL:
13728 		kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu);
13729 		return kvm_skip_emulated_instruction(vcpu);
13730 
13731 	default:
13732 		kvm_inject_gp(vcpu, 0);
13733 		return 1;
13734 	}
13735 }
13736 EXPORT_SYMBOL_GPL(kvm_handle_invpcid);
13737 
complete_sev_es_emulated_mmio(struct kvm_vcpu * vcpu)13738 static int complete_sev_es_emulated_mmio(struct kvm_vcpu *vcpu)
13739 {
13740 	struct kvm_run *run = vcpu->run;
13741 	struct kvm_mmio_fragment *frag;
13742 	unsigned int len;
13743 
13744 	BUG_ON(!vcpu->mmio_needed);
13745 
13746 	/* Complete previous fragment */
13747 	frag = &vcpu->mmio_fragments[vcpu->mmio_cur_fragment];
13748 	len = min(8u, frag->len);
13749 	if (!vcpu->mmio_is_write)
13750 		memcpy(frag->data, run->mmio.data, len);
13751 
13752 	if (frag->len <= 8) {
13753 		/* Switch to the next fragment. */
13754 		frag++;
13755 		vcpu->mmio_cur_fragment++;
13756 	} else {
13757 		/* Go forward to the next mmio piece. */
13758 		frag->data += len;
13759 		frag->gpa += len;
13760 		frag->len -= len;
13761 	}
13762 
13763 	if (vcpu->mmio_cur_fragment >= vcpu->mmio_nr_fragments) {
13764 		vcpu->mmio_needed = 0;
13765 
13766 		// VMG change, at this point, we're always done
13767 		// RIP has already been advanced
13768 		return 1;
13769 	}
13770 
13771 	// More MMIO is needed
13772 	run->mmio.phys_addr = frag->gpa;
13773 	run->mmio.len = min(8u, frag->len);
13774 	run->mmio.is_write = vcpu->mmio_is_write;
13775 	if (run->mmio.is_write)
13776 		memcpy(run->mmio.data, frag->data, min(8u, frag->len));
13777 	run->exit_reason = KVM_EXIT_MMIO;
13778 
13779 	vcpu->arch.complete_userspace_io = complete_sev_es_emulated_mmio;
13780 
13781 	return 0;
13782 }
13783 
kvm_sev_es_mmio_write(struct kvm_vcpu * vcpu,gpa_t gpa,unsigned int bytes,void * data)13784 int kvm_sev_es_mmio_write(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned int bytes,
13785 			  void *data)
13786 {
13787 	int handled;
13788 	struct kvm_mmio_fragment *frag;
13789 
13790 	if (!data)
13791 		return -EINVAL;
13792 
13793 	handled = write_emultor.read_write_mmio(vcpu, gpa, bytes, data);
13794 	if (handled == bytes)
13795 		return 1;
13796 
13797 	bytes -= handled;
13798 	gpa += handled;
13799 	data += handled;
13800 
13801 	/*TODO: Check if need to increment number of frags */
13802 	frag = vcpu->mmio_fragments;
13803 	vcpu->mmio_nr_fragments = 1;
13804 	frag->len = bytes;
13805 	frag->gpa = gpa;
13806 	frag->data = data;
13807 
13808 	vcpu->mmio_needed = 1;
13809 	vcpu->mmio_cur_fragment = 0;
13810 
13811 	vcpu->run->mmio.phys_addr = gpa;
13812 	vcpu->run->mmio.len = min(8u, frag->len);
13813 	vcpu->run->mmio.is_write = 1;
13814 	memcpy(vcpu->run->mmio.data, frag->data, min(8u, frag->len));
13815 	vcpu->run->exit_reason = KVM_EXIT_MMIO;
13816 
13817 	vcpu->arch.complete_userspace_io = complete_sev_es_emulated_mmio;
13818 
13819 	return 0;
13820 }
13821 EXPORT_SYMBOL_GPL(kvm_sev_es_mmio_write);
13822 
kvm_sev_es_mmio_read(struct kvm_vcpu * vcpu,gpa_t gpa,unsigned int bytes,void * data)13823 int kvm_sev_es_mmio_read(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned int bytes,
13824 			 void *data)
13825 {
13826 	int handled;
13827 	struct kvm_mmio_fragment *frag;
13828 
13829 	if (!data)
13830 		return -EINVAL;
13831 
13832 	handled = read_emultor.read_write_mmio(vcpu, gpa, bytes, data);
13833 	if (handled == bytes)
13834 		return 1;
13835 
13836 	bytes -= handled;
13837 	gpa += handled;
13838 	data += handled;
13839 
13840 	/*TODO: Check if need to increment number of frags */
13841 	frag = vcpu->mmio_fragments;
13842 	vcpu->mmio_nr_fragments = 1;
13843 	frag->len = bytes;
13844 	frag->gpa = gpa;
13845 	frag->data = data;
13846 
13847 	vcpu->mmio_needed = 1;
13848 	vcpu->mmio_cur_fragment = 0;
13849 
13850 	vcpu->run->mmio.phys_addr = gpa;
13851 	vcpu->run->mmio.len = min(8u, frag->len);
13852 	vcpu->run->mmio.is_write = 0;
13853 	vcpu->run->exit_reason = KVM_EXIT_MMIO;
13854 
13855 	vcpu->arch.complete_userspace_io = complete_sev_es_emulated_mmio;
13856 
13857 	return 0;
13858 }
13859 EXPORT_SYMBOL_GPL(kvm_sev_es_mmio_read);
13860 
advance_sev_es_emulated_pio(struct kvm_vcpu * vcpu,unsigned count,int size)13861 static void advance_sev_es_emulated_pio(struct kvm_vcpu *vcpu, unsigned count, int size)
13862 {
13863 	vcpu->arch.sev_pio_count -= count;
13864 	vcpu->arch.sev_pio_data += count * size;
13865 }
13866 
13867 static int kvm_sev_es_outs(struct kvm_vcpu *vcpu, unsigned int size,
13868 			   unsigned int port);
13869 
complete_sev_es_emulated_outs(struct kvm_vcpu * vcpu)13870 static int complete_sev_es_emulated_outs(struct kvm_vcpu *vcpu)
13871 {
13872 	int size = vcpu->arch.pio.size;
13873 	int port = vcpu->arch.pio.port;
13874 
13875 	vcpu->arch.pio.count = 0;
13876 	if (vcpu->arch.sev_pio_count)
13877 		return kvm_sev_es_outs(vcpu, size, port);
13878 	return 1;
13879 }
13880 
kvm_sev_es_outs(struct kvm_vcpu * vcpu,unsigned int size,unsigned int port)13881 static int kvm_sev_es_outs(struct kvm_vcpu *vcpu, unsigned int size,
13882 			   unsigned int port)
13883 {
13884 	for (;;) {
13885 		unsigned int count =
13886 			min_t(unsigned int, PAGE_SIZE / size, vcpu->arch.sev_pio_count);
13887 		int ret = emulator_pio_out(vcpu, size, port, vcpu->arch.sev_pio_data, count);
13888 
13889 		/* memcpy done already by emulator_pio_out.  */
13890 		advance_sev_es_emulated_pio(vcpu, count, size);
13891 		if (!ret)
13892 			break;
13893 
13894 		/* Emulation done by the kernel.  */
13895 		if (!vcpu->arch.sev_pio_count)
13896 			return 1;
13897 	}
13898 
13899 	vcpu->arch.complete_userspace_io = complete_sev_es_emulated_outs;
13900 	return 0;
13901 }
13902 
13903 static int kvm_sev_es_ins(struct kvm_vcpu *vcpu, unsigned int size,
13904 			  unsigned int port);
13905 
complete_sev_es_emulated_ins(struct kvm_vcpu * vcpu)13906 static int complete_sev_es_emulated_ins(struct kvm_vcpu *vcpu)
13907 {
13908 	unsigned count = vcpu->arch.pio.count;
13909 	int size = vcpu->arch.pio.size;
13910 	int port = vcpu->arch.pio.port;
13911 
13912 	complete_emulator_pio_in(vcpu, vcpu->arch.sev_pio_data);
13913 	advance_sev_es_emulated_pio(vcpu, count, size);
13914 	if (vcpu->arch.sev_pio_count)
13915 		return kvm_sev_es_ins(vcpu, size, port);
13916 	return 1;
13917 }
13918 
kvm_sev_es_ins(struct kvm_vcpu * vcpu,unsigned int size,unsigned int port)13919 static int kvm_sev_es_ins(struct kvm_vcpu *vcpu, unsigned int size,
13920 			  unsigned int port)
13921 {
13922 	for (;;) {
13923 		unsigned int count =
13924 			min_t(unsigned int, PAGE_SIZE / size, vcpu->arch.sev_pio_count);
13925 		if (!emulator_pio_in(vcpu, size, port, vcpu->arch.sev_pio_data, count))
13926 			break;
13927 
13928 		/* Emulation done by the kernel.  */
13929 		advance_sev_es_emulated_pio(vcpu, count, size);
13930 		if (!vcpu->arch.sev_pio_count)
13931 			return 1;
13932 	}
13933 
13934 	vcpu->arch.complete_userspace_io = complete_sev_es_emulated_ins;
13935 	return 0;
13936 }
13937 
kvm_sev_es_string_io(struct kvm_vcpu * vcpu,unsigned int size,unsigned int port,void * data,unsigned int count,int in)13938 int kvm_sev_es_string_io(struct kvm_vcpu *vcpu, unsigned int size,
13939 			 unsigned int port, void *data,  unsigned int count,
13940 			 int in)
13941 {
13942 	vcpu->arch.sev_pio_data = data;
13943 	vcpu->arch.sev_pio_count = count;
13944 	return in ? kvm_sev_es_ins(vcpu, size, port)
13945 		  : kvm_sev_es_outs(vcpu, size, port);
13946 }
13947 EXPORT_SYMBOL_GPL(kvm_sev_es_string_io);
13948 
13949 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_entry);
13950 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit);
13951 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_fast_mmio);
13952 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_virq);
13953 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_page_fault);
13954 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_msr);
13955 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_cr);
13956 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmenter);
13957 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmexit);
13958 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmexit_inject);
13959 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intr_vmexit);
13960 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmenter_failed);
13961 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_invlpga);
13962 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_skinit);
13963 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intercepts);
13964 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_write_tsc_offset);
13965 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_ple_window_update);
13966 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_pml_full);
13967 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_pi_irte_update);
13968 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_unaccelerated_access);
13969 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_incomplete_ipi);
13970 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_ga_log);
13971 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_kick_vcpu_slowpath);
13972 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_doorbell);
13973 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_apicv_accept_irq);
13974 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_enter);
13975 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_exit);
13976 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_msr_protocol_enter);
13977 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_msr_protocol_exit);
13978 
kvm_x86_init(void)13979 static int __init kvm_x86_init(void)
13980 {
13981 	kvm_mmu_x86_module_init();
13982 	mitigate_smt_rsb &= boot_cpu_has_bug(X86_BUG_SMT_RSB) && cpu_smt_possible();
13983 	return 0;
13984 }
13985 module_init(kvm_x86_init);
13986 
kvm_x86_exit(void)13987 static void __exit kvm_x86_exit(void)
13988 {
13989 	WARN_ON_ONCE(static_branch_unlikely(&kvm_has_noapic_vcpu));
13990 }
13991 module_exit(kvm_x86_exit);
13992