1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
4  * Author: Christoffer Dall <c.dall@virtualopensystems.com>
5  */
6 
7 #include <linux/bug.h>
8 #include <linux/cpu_pm.h>
9 #include <linux/errno.h>
10 #include <linux/err.h>
11 #include <linux/kvm_host.h>
12 #include <linux/list.h>
13 #include <linux/module.h>
14 #include <linux/vmalloc.h>
15 #include <linux/fs.h>
16 #include <linux/mman.h>
17 #include <linux/sched.h>
18 #include <linux/kvm.h>
19 #include <linux/kvm_irqfd.h>
20 #include <linux/irqbypass.h>
21 #include <linux/sched/stat.h>
22 #include <linux/psci.h>
23 #include <trace/events/kvm.h>
24 
25 #define CREATE_TRACE_POINTS
26 #include "trace_arm.h"
27 
28 #include <linux/uaccess.h>
29 #include <asm/ptrace.h>
30 #include <asm/mman.h>
31 #include <asm/tlbflush.h>
32 #include <asm/cacheflush.h>
33 #include <asm/cpufeature.h>
34 #include <asm/virt.h>
35 #include <asm/kvm_arm.h>
36 #include <asm/kvm_asm.h>
37 #include <asm/kvm_mmu.h>
38 #include <asm/kvm_emulate.h>
39 #include <asm/sections.h>
40 
41 #include <kvm/arm_hypercalls.h>
42 #include <kvm/arm_pmu.h>
43 #include <kvm/arm_psci.h>
44 
45 #ifdef REQUIRES_VIRT
46 __asm__(".arch_extension	virt");
47 #endif
48 
49 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT;
50 DEFINE_STATIC_KEY_FALSE(kvm_protected_mode_initialized);
51 
52 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
53 
54 static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
55 unsigned long kvm_arm_hyp_percpu_base[NR_CPUS];
56 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
57 
58 /* The VMID used in the VTTBR */
59 static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
60 static u32 kvm_next_vmid;
61 static DEFINE_SPINLOCK(kvm_vmid_lock);
62 
63 static bool vgic_present;
64 
65 static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled);
66 DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
67 
kvm_arch_vcpu_should_kick(struct kvm_vcpu * vcpu)68 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
69 {
70 	return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
71 }
72 
kvm_arch_hardware_setup(void * opaque)73 int kvm_arch_hardware_setup(void *opaque)
74 {
75 	return 0;
76 }
77 
kvm_arch_check_processor_compat(void * opaque)78 int kvm_arch_check_processor_compat(void *opaque)
79 {
80 	return 0;
81 }
82 
kvm_vm_ioctl_enable_cap(struct kvm * kvm,struct kvm_enable_cap * cap)83 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
84 			    struct kvm_enable_cap *cap)
85 {
86 	int r;
87 
88 	if (cap->flags)
89 		return -EINVAL;
90 
91 	switch (cap->cap) {
92 	case KVM_CAP_ARM_NISV_TO_USER:
93 		r = 0;
94 		kvm->arch.return_nisv_io_abort_to_user = true;
95 		break;
96 	default:
97 		r = -EINVAL;
98 		break;
99 	}
100 
101 	return r;
102 }
103 
kvm_arm_default_max_vcpus(void)104 static int kvm_arm_default_max_vcpus(void)
105 {
106 	return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
107 }
108 
set_default_spectre(struct kvm * kvm)109 static void set_default_spectre(struct kvm *kvm)
110 {
111 	/*
112 	 * The default is to expose CSV2 == 1 if the HW isn't affected.
113 	 * Although this is a per-CPU feature, we make it global because
114 	 * asymmetric systems are just a nuisance.
115 	 *
116 	 * Userspace can override this as long as it doesn't promise
117 	 * the impossible.
118 	 */
119 	if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED)
120 		kvm->arch.pfr0_csv2 = 1;
121 	if (arm64_get_meltdown_state() == SPECTRE_UNAFFECTED)
122 		kvm->arch.pfr0_csv3 = 1;
123 }
124 
125 /**
126  * kvm_arch_init_vm - initializes a VM data structure
127  * @kvm:	pointer to the KVM struct
128  */
kvm_arch_init_vm(struct kvm * kvm,unsigned long type)129 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
130 {
131 	int ret;
132 
133 	ret = kvm_arm_setup_stage2(kvm, type);
134 	if (ret)
135 		return ret;
136 
137 	ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu);
138 	if (ret)
139 		return ret;
140 
141 	ret = create_hyp_mappings(kvm, kvm + 1, PAGE_HYP);
142 	if (ret)
143 		goto out_free_stage2_pgd;
144 
145 	kvm_vgic_early_init(kvm);
146 
147 	/* The maximum number of VCPUs is limited by the host's GIC model */
148 	kvm->arch.max_vcpus = kvm_arm_default_max_vcpus();
149 
150 	set_default_spectre(kvm);
151 
152 	return ret;
153 out_free_stage2_pgd:
154 	kvm_free_stage2_pgd(&kvm->arch.mmu);
155 	return ret;
156 }
157 
kvm_arch_vcpu_fault(struct kvm_vcpu * vcpu,struct vm_fault * vmf)158 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
159 {
160 	return VM_FAULT_SIGBUS;
161 }
162 
163 
164 /**
165  * kvm_arch_destroy_vm - destroy the VM data structure
166  * @kvm:	pointer to the KVM struct
167  */
kvm_arch_destroy_vm(struct kvm * kvm)168 void kvm_arch_destroy_vm(struct kvm *kvm)
169 {
170 	int i;
171 
172 	bitmap_free(kvm->arch.pmu_filter);
173 
174 	kvm_vgic_destroy(kvm);
175 
176 	for (i = 0; i < KVM_MAX_VCPUS; ++i) {
177 		if (kvm->vcpus[i]) {
178 			kvm_vcpu_destroy(kvm->vcpus[i]);
179 			kvm->vcpus[i] = NULL;
180 		}
181 	}
182 	atomic_set(&kvm->online_vcpus, 0);
183 }
184 
kvm_vm_ioctl_check_extension(struct kvm * kvm,long ext)185 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
186 {
187 	int r;
188 	switch (ext) {
189 	case KVM_CAP_IRQCHIP:
190 		r = vgic_present;
191 		break;
192 	case KVM_CAP_IOEVENTFD:
193 	case KVM_CAP_DEVICE_CTRL:
194 	case KVM_CAP_USER_MEMORY:
195 	case KVM_CAP_SYNC_MMU:
196 	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
197 	case KVM_CAP_ONE_REG:
198 	case KVM_CAP_ARM_PSCI:
199 	case KVM_CAP_ARM_PSCI_0_2:
200 	case KVM_CAP_READONLY_MEM:
201 	case KVM_CAP_MP_STATE:
202 	case KVM_CAP_IMMEDIATE_EXIT:
203 	case KVM_CAP_VCPU_EVENTS:
204 	case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
205 	case KVM_CAP_ARM_NISV_TO_USER:
206 	case KVM_CAP_ARM_INJECT_EXT_DABT:
207 	case KVM_CAP_SET_GUEST_DEBUG:
208 	case KVM_CAP_VCPU_ATTRIBUTES:
209 	case KVM_CAP_PTP_KVM:
210 		r = 1;
211 		break;
212 	case KVM_CAP_SET_GUEST_DEBUG2:
213 		return KVM_GUESTDBG_VALID_MASK;
214 	case KVM_CAP_ARM_SET_DEVICE_ADDR:
215 		r = 1;
216 		break;
217 	case KVM_CAP_NR_VCPUS:
218 		r = num_online_cpus();
219 		break;
220 	case KVM_CAP_MAX_VCPUS:
221 	case KVM_CAP_MAX_VCPU_ID:
222 		if (kvm)
223 			r = kvm->arch.max_vcpus;
224 		else
225 			r = kvm_arm_default_max_vcpus();
226 		break;
227 	case KVM_CAP_MSI_DEVID:
228 		if (!kvm)
229 			r = -EINVAL;
230 		else
231 			r = kvm->arch.vgic.msis_require_devid;
232 		break;
233 	case KVM_CAP_ARM_USER_IRQ:
234 		/*
235 		 * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
236 		 * (bump this number if adding more devices)
237 		 */
238 		r = 1;
239 		break;
240 	case KVM_CAP_STEAL_TIME:
241 		r = kvm_arm_pvtime_supported();
242 		break;
243 	case KVM_CAP_ARM_EL1_32BIT:
244 		r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1);
245 		break;
246 	case KVM_CAP_GUEST_DEBUG_HW_BPS:
247 		r = get_num_brps();
248 		break;
249 	case KVM_CAP_GUEST_DEBUG_HW_WPS:
250 		r = get_num_wrps();
251 		break;
252 	case KVM_CAP_ARM_PMU_V3:
253 		r = kvm_arm_support_pmu_v3();
254 		break;
255 	case KVM_CAP_ARM_INJECT_SERROR_ESR:
256 		r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN);
257 		break;
258 	case KVM_CAP_ARM_VM_IPA_SIZE:
259 		r = get_kvm_ipa_limit();
260 		break;
261 	case KVM_CAP_ARM_SVE:
262 		r = system_supports_sve();
263 		break;
264 	case KVM_CAP_ARM_PTRAUTH_ADDRESS:
265 	case KVM_CAP_ARM_PTRAUTH_GENERIC:
266 		r = system_has_full_ptr_auth();
267 		break;
268 	default:
269 		r = 0;
270 	}
271 
272 	return r;
273 }
274 
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)275 long kvm_arch_dev_ioctl(struct file *filp,
276 			unsigned int ioctl, unsigned long arg)
277 {
278 	return -EINVAL;
279 }
280 
kvm_arch_alloc_vm(void)281 struct kvm *kvm_arch_alloc_vm(void)
282 {
283 	if (!has_vhe())
284 		return kzalloc(sizeof(struct kvm), GFP_KERNEL);
285 
286 	return vzalloc(sizeof(struct kvm));
287 }
288 
kvm_arch_free_vm(struct kvm * kvm)289 void kvm_arch_free_vm(struct kvm *kvm)
290 {
291 	if (!has_vhe())
292 		kfree(kvm);
293 	else
294 		vfree(kvm);
295 }
296 
kvm_arch_vcpu_precreate(struct kvm * kvm,unsigned int id)297 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
298 {
299 	if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
300 		return -EBUSY;
301 
302 	if (id >= kvm->arch.max_vcpus)
303 		return -EINVAL;
304 
305 	return 0;
306 }
307 
kvm_arch_vcpu_create(struct kvm_vcpu * vcpu)308 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
309 {
310 	int err;
311 
312 	/* Force users to call KVM_ARM_VCPU_INIT */
313 	vcpu->arch.target = -1;
314 	bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
315 
316 	vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
317 
318 	/* Set up the timer */
319 	kvm_timer_vcpu_init(vcpu);
320 
321 	kvm_pmu_vcpu_init(vcpu);
322 
323 	kvm_arm_reset_debug_ptr(vcpu);
324 
325 	kvm_arm_pvtime_vcpu_init(&vcpu->arch);
326 
327 	vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
328 
329 	err = kvm_vgic_vcpu_init(vcpu);
330 	if (err)
331 		return err;
332 
333 	return create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP);
334 }
335 
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)336 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
337 {
338 }
339 
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)340 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
341 {
342 	if (vcpu->arch.has_run_once && unlikely(!irqchip_in_kernel(vcpu->kvm)))
343 		static_branch_dec(&userspace_irqchip_in_use);
344 
345 	kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
346 	kvm_timer_vcpu_terminate(vcpu);
347 	kvm_pmu_vcpu_destroy(vcpu);
348 
349 	kvm_arm_vcpu_destroy(vcpu);
350 }
351 
kvm_cpu_has_pending_timer(struct kvm_vcpu * vcpu)352 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
353 {
354 	return kvm_timer_is_pending(vcpu);
355 }
356 
kvm_arch_vcpu_blocking(struct kvm_vcpu * vcpu)357 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
358 {
359 	/*
360 	 * If we're about to block (most likely because we've just hit a
361 	 * WFI), we need to sync back the state of the GIC CPU interface
362 	 * so that we have the latest PMR and group enables. This ensures
363 	 * that kvm_arch_vcpu_runnable has up-to-date data to decide
364 	 * whether we have pending interrupts.
365 	 *
366 	 * For the same reason, we want to tell GICv4 that we need
367 	 * doorbells to be signalled, should an interrupt become pending.
368 	 */
369 	preempt_disable();
370 	kvm_vgic_vmcr_sync(vcpu);
371 	vgic_v4_put(vcpu, true);
372 	preempt_enable();
373 }
374 
kvm_arch_vcpu_unblocking(struct kvm_vcpu * vcpu)375 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
376 {
377 	preempt_disable();
378 	vgic_v4_load(vcpu);
379 	preempt_enable();
380 }
381 
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)382 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
383 {
384 	struct kvm_s2_mmu *mmu;
385 	int *last_ran;
386 
387 	mmu = vcpu->arch.hw_mmu;
388 	last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
389 
390 	/*
391 	 * We guarantee that both TLBs and I-cache are private to each
392 	 * vcpu. If detecting that a vcpu from the same VM has
393 	 * previously run on the same physical CPU, call into the
394 	 * hypervisor code to nuke the relevant contexts.
395 	 *
396 	 * We might get preempted before the vCPU actually runs, but
397 	 * over-invalidation doesn't affect correctness.
398 	 */
399 	if (*last_ran != vcpu->vcpu_id) {
400 		kvm_call_hyp(__kvm_flush_cpu_context, mmu);
401 		*last_ran = vcpu->vcpu_id;
402 	}
403 
404 	vcpu->cpu = cpu;
405 
406 	kvm_vgic_load(vcpu);
407 	kvm_timer_vcpu_load(vcpu);
408 	if (has_vhe())
409 		kvm_vcpu_load_sysregs_vhe(vcpu);
410 	kvm_arch_vcpu_load_fp(vcpu);
411 	kvm_vcpu_pmu_restore_guest(vcpu);
412 	if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
413 		kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
414 
415 	if (single_task_running())
416 		vcpu_clear_wfx_traps(vcpu);
417 	else
418 		vcpu_set_wfx_traps(vcpu);
419 
420 	if (vcpu_has_ptrauth(vcpu))
421 		vcpu_ptrauth_disable(vcpu);
422 	kvm_arch_vcpu_load_debug_state_flags(vcpu);
423 }
424 
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)425 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
426 {
427 	kvm_arch_vcpu_put_debug_state_flags(vcpu);
428 	kvm_arch_vcpu_put_fp(vcpu);
429 	if (has_vhe())
430 		kvm_vcpu_put_sysregs_vhe(vcpu);
431 	kvm_timer_vcpu_put(vcpu);
432 	kvm_vgic_put(vcpu);
433 	kvm_vcpu_pmu_restore_host(vcpu);
434 
435 	vcpu->cpu = -1;
436 }
437 
vcpu_power_off(struct kvm_vcpu * vcpu)438 static void vcpu_power_off(struct kvm_vcpu *vcpu)
439 {
440 	vcpu->arch.power_off = true;
441 	kvm_make_request(KVM_REQ_SLEEP, vcpu);
442 	kvm_vcpu_kick(vcpu);
443 }
444 
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)445 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
446 				    struct kvm_mp_state *mp_state)
447 {
448 	if (vcpu->arch.power_off)
449 		mp_state->mp_state = KVM_MP_STATE_STOPPED;
450 	else
451 		mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
452 
453 	return 0;
454 }
455 
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)456 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
457 				    struct kvm_mp_state *mp_state)
458 {
459 	int ret = 0;
460 
461 	switch (mp_state->mp_state) {
462 	case KVM_MP_STATE_RUNNABLE:
463 		vcpu->arch.power_off = false;
464 		break;
465 	case KVM_MP_STATE_STOPPED:
466 		vcpu_power_off(vcpu);
467 		break;
468 	default:
469 		ret = -EINVAL;
470 	}
471 
472 	return ret;
473 }
474 
475 /**
476  * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
477  * @v:		The VCPU pointer
478  *
479  * If the guest CPU is not waiting for interrupts or an interrupt line is
480  * asserted, the CPU is by definition runnable.
481  */
kvm_arch_vcpu_runnable(struct kvm_vcpu * v)482 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
483 {
484 	bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
485 	return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
486 		&& !v->arch.power_off && !v->arch.pause);
487 }
488 
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)489 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
490 {
491 	return vcpu_mode_priv(vcpu);
492 }
493 
494 /* Just ensure a guest exit from a particular CPU */
exit_vm_noop(void * info)495 static void exit_vm_noop(void *info)
496 {
497 }
498 
force_vm_exit(const cpumask_t * mask)499 void force_vm_exit(const cpumask_t *mask)
500 {
501 	preempt_disable();
502 	smp_call_function_many(mask, exit_vm_noop, NULL, true);
503 	preempt_enable();
504 }
505 
506 /**
507  * need_new_vmid_gen - check that the VMID is still valid
508  * @vmid: The VMID to check
509  *
510  * return true if there is a new generation of VMIDs being used
511  *
512  * The hardware supports a limited set of values with the value zero reserved
513  * for the host, so we check if an assigned value belongs to a previous
514  * generation, which requires us to assign a new value. If we're the first to
515  * use a VMID for the new generation, we must flush necessary caches and TLBs
516  * on all CPUs.
517  */
need_new_vmid_gen(struct kvm_vmid * vmid)518 static bool need_new_vmid_gen(struct kvm_vmid *vmid)
519 {
520 	u64 current_vmid_gen = atomic64_read(&kvm_vmid_gen);
521 	smp_rmb(); /* Orders read of kvm_vmid_gen and kvm->arch.vmid */
522 	return unlikely(READ_ONCE(vmid->vmid_gen) != current_vmid_gen);
523 }
524 
525 /**
526  * update_vmid - Update the vmid with a valid VMID for the current generation
527  * @vmid: The stage-2 VMID information struct
528  */
update_vmid(struct kvm_vmid * vmid)529 static void update_vmid(struct kvm_vmid *vmid)
530 {
531 	if (!need_new_vmid_gen(vmid))
532 		return;
533 
534 	spin_lock(&kvm_vmid_lock);
535 
536 	/*
537 	 * We need to re-check the vmid_gen here to ensure that if another vcpu
538 	 * already allocated a valid vmid for this vm, then this vcpu should
539 	 * use the same vmid.
540 	 */
541 	if (!need_new_vmid_gen(vmid)) {
542 		spin_unlock(&kvm_vmid_lock);
543 		return;
544 	}
545 
546 	/* First user of a new VMID generation? */
547 	if (unlikely(kvm_next_vmid == 0)) {
548 		atomic64_inc(&kvm_vmid_gen);
549 		kvm_next_vmid = 1;
550 
551 		/*
552 		 * On SMP we know no other CPUs can use this CPU's or each
553 		 * other's VMID after force_vm_exit returns since the
554 		 * kvm_vmid_lock blocks them from reentry to the guest.
555 		 */
556 		force_vm_exit(cpu_all_mask);
557 		/*
558 		 * Now broadcast TLB + ICACHE invalidation over the inner
559 		 * shareable domain to make sure all data structures are
560 		 * clean.
561 		 */
562 		kvm_call_hyp(__kvm_flush_vm_context);
563 	}
564 
565 	vmid->vmid = kvm_next_vmid;
566 	kvm_next_vmid++;
567 	kvm_next_vmid &= (1 << kvm_get_vmid_bits()) - 1;
568 
569 	smp_wmb();
570 	WRITE_ONCE(vmid->vmid_gen, atomic64_read(&kvm_vmid_gen));
571 
572 	spin_unlock(&kvm_vmid_lock);
573 }
574 
kvm_vcpu_first_run_init(struct kvm_vcpu * vcpu)575 static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu)
576 {
577 	struct kvm *kvm = vcpu->kvm;
578 	int ret = 0;
579 
580 	if (likely(vcpu->arch.has_run_once))
581 		return 0;
582 
583 	if (!kvm_arm_vcpu_is_finalized(vcpu))
584 		return -EPERM;
585 
586 	vcpu->arch.has_run_once = true;
587 
588 	kvm_arm_vcpu_init_debug(vcpu);
589 
590 	if (likely(irqchip_in_kernel(kvm))) {
591 		/*
592 		 * Map the VGIC hardware resources before running a vcpu the
593 		 * first time on this VM.
594 		 */
595 		ret = kvm_vgic_map_resources(kvm);
596 		if (ret)
597 			return ret;
598 	} else {
599 		/*
600 		 * Tell the rest of the code that there are userspace irqchip
601 		 * VMs in the wild.
602 		 */
603 		static_branch_inc(&userspace_irqchip_in_use);
604 	}
605 
606 	ret = kvm_timer_enable(vcpu);
607 	if (ret)
608 		return ret;
609 
610 	ret = kvm_arm_pmu_v3_enable(vcpu);
611 
612 	return ret;
613 }
614 
kvm_arch_intc_initialized(struct kvm * kvm)615 bool kvm_arch_intc_initialized(struct kvm *kvm)
616 {
617 	return vgic_initialized(kvm);
618 }
619 
kvm_arm_halt_guest(struct kvm * kvm)620 void kvm_arm_halt_guest(struct kvm *kvm)
621 {
622 	int i;
623 	struct kvm_vcpu *vcpu;
624 
625 	kvm_for_each_vcpu(i, vcpu, kvm)
626 		vcpu->arch.pause = true;
627 	kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
628 }
629 
kvm_arm_resume_guest(struct kvm * kvm)630 void kvm_arm_resume_guest(struct kvm *kvm)
631 {
632 	int i;
633 	struct kvm_vcpu *vcpu;
634 
635 	kvm_for_each_vcpu(i, vcpu, kvm) {
636 		vcpu->arch.pause = false;
637 		rcuwait_wake_up(kvm_arch_vcpu_get_wait(vcpu));
638 	}
639 }
640 
vcpu_req_sleep(struct kvm_vcpu * vcpu)641 static void vcpu_req_sleep(struct kvm_vcpu *vcpu)
642 {
643 	struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
644 
645 	rcuwait_wait_event(wait,
646 			   (!vcpu->arch.power_off) &&(!vcpu->arch.pause),
647 			   TASK_INTERRUPTIBLE);
648 
649 	if (vcpu->arch.power_off || vcpu->arch.pause) {
650 		/* Awaken to handle a signal, request we sleep again later. */
651 		kvm_make_request(KVM_REQ_SLEEP, vcpu);
652 	}
653 
654 	/*
655 	 * Make sure we will observe a potential reset request if we've
656 	 * observed a change to the power state. Pairs with the smp_wmb() in
657 	 * kvm_psci_vcpu_on().
658 	 */
659 	smp_rmb();
660 }
661 
kvm_vcpu_initialized(struct kvm_vcpu * vcpu)662 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
663 {
664 	return vcpu->arch.target >= 0;
665 }
666 
check_vcpu_requests(struct kvm_vcpu * vcpu)667 static void check_vcpu_requests(struct kvm_vcpu *vcpu)
668 {
669 	if (kvm_request_pending(vcpu)) {
670 		if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
671 			vcpu_req_sleep(vcpu);
672 
673 		if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
674 			kvm_reset_vcpu(vcpu);
675 
676 		/*
677 		 * Clear IRQ_PENDING requests that were made to guarantee
678 		 * that a VCPU sees new virtual interrupts.
679 		 */
680 		kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
681 
682 		if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
683 			kvm_update_stolen_time(vcpu);
684 
685 		if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
686 			/* The distributor enable bits were changed */
687 			preempt_disable();
688 			vgic_v4_put(vcpu, false);
689 			vgic_v4_load(vcpu);
690 			preempt_enable();
691 		}
692 	}
693 }
694 
695 /**
696  * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
697  * @vcpu:	The VCPU pointer
698  *
699  * This function is called through the VCPU_RUN ioctl called from user space. It
700  * will execute VM code in a loop until the time slice for the process is used
701  * or some emulation is needed from user space in which case the function will
702  * return with return value 0 and with the kvm_run structure filled in with the
703  * required data for the requested emulation.
704  */
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)705 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
706 {
707 	struct kvm_run *run = vcpu->run;
708 	int ret;
709 
710 	if (unlikely(!kvm_vcpu_initialized(vcpu)))
711 		return -ENOEXEC;
712 
713 	ret = kvm_vcpu_first_run_init(vcpu);
714 	if (ret)
715 		return ret;
716 
717 	if (run->exit_reason == KVM_EXIT_MMIO) {
718 		ret = kvm_handle_mmio_return(vcpu);
719 		if (ret)
720 			return ret;
721 	}
722 
723 	if (run->immediate_exit)
724 		return -EINTR;
725 
726 	vcpu_load(vcpu);
727 
728 	kvm_sigset_activate(vcpu);
729 
730 	ret = 1;
731 	run->exit_reason = KVM_EXIT_UNKNOWN;
732 	while (ret > 0) {
733 		/*
734 		 * Check conditions before entering the guest
735 		 */
736 		cond_resched();
737 
738 		update_vmid(&vcpu->arch.hw_mmu->vmid);
739 
740 		check_vcpu_requests(vcpu);
741 
742 		/*
743 		 * Preparing the interrupts to be injected also
744 		 * involves poking the GIC, which must be done in a
745 		 * non-preemptible context.
746 		 */
747 		preempt_disable();
748 
749 		kvm_pmu_flush_hwstate(vcpu);
750 
751 		local_irq_disable();
752 
753 		kvm_vgic_flush_hwstate(vcpu);
754 
755 		/*
756 		 * Exit if we have a signal pending so that we can deliver the
757 		 * signal to user space.
758 		 */
759 		if (signal_pending(current)) {
760 			ret = -EINTR;
761 			run->exit_reason = KVM_EXIT_INTR;
762 		}
763 
764 		/*
765 		 * If we're using a userspace irqchip, then check if we need
766 		 * to tell a userspace irqchip about timer or PMU level
767 		 * changes and if so, exit to userspace (the actual level
768 		 * state gets updated in kvm_timer_update_run and
769 		 * kvm_pmu_update_run below).
770 		 */
771 		if (static_branch_unlikely(&userspace_irqchip_in_use)) {
772 			if (kvm_timer_should_notify_user(vcpu) ||
773 			    kvm_pmu_should_notify_user(vcpu)) {
774 				ret = -EINTR;
775 				run->exit_reason = KVM_EXIT_INTR;
776 			}
777 		}
778 
779 		/*
780 		 * Ensure we set mode to IN_GUEST_MODE after we disable
781 		 * interrupts and before the final VCPU requests check.
782 		 * See the comment in kvm_vcpu_exiting_guest_mode() and
783 		 * Documentation/virt/kvm/vcpu-requests.rst
784 		 */
785 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
786 
787 		if (ret <= 0 || need_new_vmid_gen(&vcpu->arch.hw_mmu->vmid) ||
788 		    kvm_request_pending(vcpu)) {
789 			vcpu->mode = OUTSIDE_GUEST_MODE;
790 			isb(); /* Ensure work in x_flush_hwstate is committed */
791 			kvm_pmu_sync_hwstate(vcpu);
792 			if (static_branch_unlikely(&userspace_irqchip_in_use))
793 				kvm_timer_sync_user(vcpu);
794 			kvm_vgic_sync_hwstate(vcpu);
795 			local_irq_enable();
796 			preempt_enable();
797 			continue;
798 		}
799 
800 		kvm_arm_setup_debug(vcpu);
801 
802 		/**************************************************************
803 		 * Enter the guest
804 		 */
805 		trace_kvm_entry(*vcpu_pc(vcpu));
806 		guest_enter_irqoff();
807 
808 		ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
809 
810 		vcpu->mode = OUTSIDE_GUEST_MODE;
811 		vcpu->stat.exits++;
812 		/*
813 		 * Back from guest
814 		 *************************************************************/
815 
816 		kvm_arm_clear_debug(vcpu);
817 
818 		/*
819 		 * We must sync the PMU state before the vgic state so
820 		 * that the vgic can properly sample the updated state of the
821 		 * interrupt line.
822 		 */
823 		kvm_pmu_sync_hwstate(vcpu);
824 
825 		/*
826 		 * Sync the vgic state before syncing the timer state because
827 		 * the timer code needs to know if the virtual timer
828 		 * interrupts are active.
829 		 */
830 		kvm_vgic_sync_hwstate(vcpu);
831 
832 		/*
833 		 * Sync the timer hardware state before enabling interrupts as
834 		 * we don't want vtimer interrupts to race with syncing the
835 		 * timer virtual interrupt state.
836 		 */
837 		if (static_branch_unlikely(&userspace_irqchip_in_use))
838 			kvm_timer_sync_user(vcpu);
839 
840 		kvm_arch_vcpu_ctxsync_fp(vcpu);
841 
842 		/*
843 		 * We may have taken a host interrupt in HYP mode (ie
844 		 * while executing the guest). This interrupt is still
845 		 * pending, as we haven't serviced it yet!
846 		 *
847 		 * We're now back in SVC mode, with interrupts
848 		 * disabled.  Enabling the interrupts now will have
849 		 * the effect of taking the interrupt again, in SVC
850 		 * mode this time.
851 		 */
852 		local_irq_enable();
853 
854 		/*
855 		 * We do local_irq_enable() before calling guest_exit() so
856 		 * that if a timer interrupt hits while running the guest we
857 		 * account that tick as being spent in the guest.  We enable
858 		 * preemption after calling guest_exit() so that if we get
859 		 * preempted we make sure ticks after that is not counted as
860 		 * guest time.
861 		 */
862 		guest_exit();
863 		trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
864 
865 		/* Exit types that need handling before we can be preempted */
866 		handle_exit_early(vcpu, ret);
867 
868 		preempt_enable();
869 
870 		/*
871 		 * The ARMv8 architecture doesn't give the hypervisor
872 		 * a mechanism to prevent a guest from dropping to AArch32 EL0
873 		 * if implemented by the CPU. If we spot the guest in such
874 		 * state and that we decided it wasn't supposed to do so (like
875 		 * with the asymmetric AArch32 case), return to userspace with
876 		 * a fatal error.
877 		 */
878 		if (!system_supports_32bit_el0() && vcpu_mode_is_32bit(vcpu)) {
879 			/*
880 			 * As we have caught the guest red-handed, decide that
881 			 * it isn't fit for purpose anymore by making the vcpu
882 			 * invalid. The VMM can try and fix it by issuing  a
883 			 * KVM_ARM_VCPU_INIT if it really wants to.
884 			 */
885 			vcpu->arch.target = -1;
886 			ret = ARM_EXCEPTION_IL;
887 		}
888 
889 		ret = handle_exit(vcpu, ret);
890 	}
891 
892 	/* Tell userspace about in-kernel device output levels */
893 	if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
894 		kvm_timer_update_run(vcpu);
895 		kvm_pmu_update_run(vcpu);
896 	}
897 
898 	kvm_sigset_deactivate(vcpu);
899 
900 	vcpu_put(vcpu);
901 	return ret;
902 }
903 
vcpu_interrupt_line(struct kvm_vcpu * vcpu,int number,bool level)904 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
905 {
906 	int bit_index;
907 	bool set;
908 	unsigned long *hcr;
909 
910 	if (number == KVM_ARM_IRQ_CPU_IRQ)
911 		bit_index = __ffs(HCR_VI);
912 	else /* KVM_ARM_IRQ_CPU_FIQ */
913 		bit_index = __ffs(HCR_VF);
914 
915 	hcr = vcpu_hcr(vcpu);
916 	if (level)
917 		set = test_and_set_bit(bit_index, hcr);
918 	else
919 		set = test_and_clear_bit(bit_index, hcr);
920 
921 	/*
922 	 * If we didn't change anything, no need to wake up or kick other CPUs
923 	 */
924 	if (set == level)
925 		return 0;
926 
927 	/*
928 	 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
929 	 * trigger a world-switch round on the running physical CPU to set the
930 	 * virtual IRQ/FIQ fields in the HCR appropriately.
931 	 */
932 	kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
933 	kvm_vcpu_kick(vcpu);
934 
935 	return 0;
936 }
937 
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_level,bool line_status)938 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
939 			  bool line_status)
940 {
941 	u32 irq = irq_level->irq;
942 	unsigned int irq_type, vcpu_idx, irq_num;
943 	int nrcpus = atomic_read(&kvm->online_vcpus);
944 	struct kvm_vcpu *vcpu = NULL;
945 	bool level = irq_level->level;
946 
947 	irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
948 	vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
949 	vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
950 	irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
951 
952 	trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
953 
954 	switch (irq_type) {
955 	case KVM_ARM_IRQ_TYPE_CPU:
956 		if (irqchip_in_kernel(kvm))
957 			return -ENXIO;
958 
959 		if (vcpu_idx >= nrcpus)
960 			return -EINVAL;
961 
962 		vcpu = kvm_get_vcpu(kvm, vcpu_idx);
963 		if (!vcpu)
964 			return -EINVAL;
965 
966 		if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
967 			return -EINVAL;
968 
969 		return vcpu_interrupt_line(vcpu, irq_num, level);
970 	case KVM_ARM_IRQ_TYPE_PPI:
971 		if (!irqchip_in_kernel(kvm))
972 			return -ENXIO;
973 
974 		if (vcpu_idx >= nrcpus)
975 			return -EINVAL;
976 
977 		vcpu = kvm_get_vcpu(kvm, vcpu_idx);
978 		if (!vcpu)
979 			return -EINVAL;
980 
981 		if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
982 			return -EINVAL;
983 
984 		return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL);
985 	case KVM_ARM_IRQ_TYPE_SPI:
986 		if (!irqchip_in_kernel(kvm))
987 			return -ENXIO;
988 
989 		if (irq_num < VGIC_NR_PRIVATE_IRQS)
990 			return -EINVAL;
991 
992 		return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL);
993 	}
994 
995 	return -EINVAL;
996 }
997 
kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)998 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
999 			       const struct kvm_vcpu_init *init)
1000 {
1001 	unsigned int i, ret;
1002 	int phys_target = kvm_target_cpu();
1003 
1004 	if (init->target != phys_target)
1005 		return -EINVAL;
1006 
1007 	/*
1008 	 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
1009 	 * use the same target.
1010 	 */
1011 	if (vcpu->arch.target != -1 && vcpu->arch.target != init->target)
1012 		return -EINVAL;
1013 
1014 	/* -ENOENT for unknown features, -EINVAL for invalid combinations. */
1015 	for (i = 0; i < sizeof(init->features) * 8; i++) {
1016 		bool set = (init->features[i / 32] & (1 << (i % 32)));
1017 
1018 		if (set && i >= KVM_VCPU_MAX_FEATURES)
1019 			return -ENOENT;
1020 
1021 		/*
1022 		 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
1023 		 * use the same feature set.
1024 		 */
1025 		if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES &&
1026 		    test_bit(i, vcpu->arch.features) != set)
1027 			return -EINVAL;
1028 
1029 		if (set)
1030 			set_bit(i, vcpu->arch.features);
1031 	}
1032 
1033 	vcpu->arch.target = phys_target;
1034 
1035 	/* Now we know what it is, we can reset it. */
1036 	ret = kvm_reset_vcpu(vcpu);
1037 	if (ret) {
1038 		vcpu->arch.target = -1;
1039 		bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
1040 	}
1041 
1042 	return ret;
1043 }
1044 
kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu * vcpu,struct kvm_vcpu_init * init)1045 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1046 					 struct kvm_vcpu_init *init)
1047 {
1048 	int ret;
1049 
1050 	ret = kvm_vcpu_set_target(vcpu, init);
1051 	if (ret)
1052 		return ret;
1053 
1054 	/*
1055 	 * Ensure a rebooted VM will fault in RAM pages and detect if the
1056 	 * guest MMU is turned off and flush the caches as needed.
1057 	 *
1058 	 * S2FWB enforces all memory accesses to RAM being cacheable,
1059 	 * ensuring that the data side is always coherent. We still
1060 	 * need to invalidate the I-cache though, as FWB does *not*
1061 	 * imply CTR_EL0.DIC.
1062 	 */
1063 	if (vcpu->arch.has_run_once) {
1064 		if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1065 			stage2_unmap_vm(vcpu->kvm);
1066 		else
1067 			__flush_icache_all();
1068 	}
1069 
1070 	vcpu_reset_hcr(vcpu);
1071 
1072 	/*
1073 	 * Handle the "start in power-off" case.
1074 	 */
1075 	if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
1076 		vcpu_power_off(vcpu);
1077 	else
1078 		vcpu->arch.power_off = false;
1079 
1080 	return 0;
1081 }
1082 
kvm_arm_vcpu_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1083 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1084 				 struct kvm_device_attr *attr)
1085 {
1086 	int ret = -ENXIO;
1087 
1088 	switch (attr->group) {
1089 	default:
1090 		ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1091 		break;
1092 	}
1093 
1094 	return ret;
1095 }
1096 
kvm_arm_vcpu_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1097 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1098 				 struct kvm_device_attr *attr)
1099 {
1100 	int ret = -ENXIO;
1101 
1102 	switch (attr->group) {
1103 	default:
1104 		ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1105 		break;
1106 	}
1107 
1108 	return ret;
1109 }
1110 
kvm_arm_vcpu_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1111 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1112 				 struct kvm_device_attr *attr)
1113 {
1114 	int ret = -ENXIO;
1115 
1116 	switch (attr->group) {
1117 	default:
1118 		ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1119 		break;
1120 	}
1121 
1122 	return ret;
1123 }
1124 
kvm_arm_vcpu_get_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1125 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1126 				   struct kvm_vcpu_events *events)
1127 {
1128 	memset(events, 0, sizeof(*events));
1129 
1130 	return __kvm_arm_vcpu_get_events(vcpu, events);
1131 }
1132 
kvm_arm_vcpu_set_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1133 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1134 				   struct kvm_vcpu_events *events)
1135 {
1136 	int i;
1137 
1138 	/* check whether the reserved field is zero */
1139 	for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1140 		if (events->reserved[i])
1141 			return -EINVAL;
1142 
1143 	/* check whether the pad field is zero */
1144 	for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1145 		if (events->exception.pad[i])
1146 			return -EINVAL;
1147 
1148 	return __kvm_arm_vcpu_set_events(vcpu, events);
1149 }
1150 
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1151 long kvm_arch_vcpu_ioctl(struct file *filp,
1152 			 unsigned int ioctl, unsigned long arg)
1153 {
1154 	struct kvm_vcpu *vcpu = filp->private_data;
1155 	void __user *argp = (void __user *)arg;
1156 	struct kvm_device_attr attr;
1157 	long r;
1158 
1159 	switch (ioctl) {
1160 	case KVM_ARM_VCPU_INIT: {
1161 		struct kvm_vcpu_init init;
1162 
1163 		r = -EFAULT;
1164 		if (copy_from_user(&init, argp, sizeof(init)))
1165 			break;
1166 
1167 		r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1168 		break;
1169 	}
1170 	case KVM_SET_ONE_REG:
1171 	case KVM_GET_ONE_REG: {
1172 		struct kvm_one_reg reg;
1173 
1174 		r = -ENOEXEC;
1175 		if (unlikely(!kvm_vcpu_initialized(vcpu)))
1176 			break;
1177 
1178 		r = -EFAULT;
1179 		if (copy_from_user(&reg, argp, sizeof(reg)))
1180 			break;
1181 
1182 		if (ioctl == KVM_SET_ONE_REG)
1183 			r = kvm_arm_set_reg(vcpu, &reg);
1184 		else
1185 			r = kvm_arm_get_reg(vcpu, &reg);
1186 		break;
1187 	}
1188 	case KVM_GET_REG_LIST: {
1189 		struct kvm_reg_list __user *user_list = argp;
1190 		struct kvm_reg_list reg_list;
1191 		unsigned n;
1192 
1193 		r = -ENOEXEC;
1194 		if (unlikely(!kvm_vcpu_initialized(vcpu)))
1195 			break;
1196 
1197 		r = -EPERM;
1198 		if (!kvm_arm_vcpu_is_finalized(vcpu))
1199 			break;
1200 
1201 		r = -EFAULT;
1202 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
1203 			break;
1204 		n = reg_list.n;
1205 		reg_list.n = kvm_arm_num_regs(vcpu);
1206 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
1207 			break;
1208 		r = -E2BIG;
1209 		if (n < reg_list.n)
1210 			break;
1211 		r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1212 		break;
1213 	}
1214 	case KVM_SET_DEVICE_ATTR: {
1215 		r = -EFAULT;
1216 		if (copy_from_user(&attr, argp, sizeof(attr)))
1217 			break;
1218 		r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1219 		break;
1220 	}
1221 	case KVM_GET_DEVICE_ATTR: {
1222 		r = -EFAULT;
1223 		if (copy_from_user(&attr, argp, sizeof(attr)))
1224 			break;
1225 		r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1226 		break;
1227 	}
1228 	case KVM_HAS_DEVICE_ATTR: {
1229 		r = -EFAULT;
1230 		if (copy_from_user(&attr, argp, sizeof(attr)))
1231 			break;
1232 		r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1233 		break;
1234 	}
1235 	case KVM_GET_VCPU_EVENTS: {
1236 		struct kvm_vcpu_events events;
1237 
1238 		if (kvm_arm_vcpu_get_events(vcpu, &events))
1239 			return -EINVAL;
1240 
1241 		if (copy_to_user(argp, &events, sizeof(events)))
1242 			return -EFAULT;
1243 
1244 		return 0;
1245 	}
1246 	case KVM_SET_VCPU_EVENTS: {
1247 		struct kvm_vcpu_events events;
1248 
1249 		if (copy_from_user(&events, argp, sizeof(events)))
1250 			return -EFAULT;
1251 
1252 		return kvm_arm_vcpu_set_events(vcpu, &events);
1253 	}
1254 	case KVM_ARM_VCPU_FINALIZE: {
1255 		int what;
1256 
1257 		if (!kvm_vcpu_initialized(vcpu))
1258 			return -ENOEXEC;
1259 
1260 		if (get_user(what, (const int __user *)argp))
1261 			return -EFAULT;
1262 
1263 		return kvm_arm_vcpu_finalize(vcpu, what);
1264 	}
1265 	default:
1266 		r = -EINVAL;
1267 	}
1268 
1269 	return r;
1270 }
1271 
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)1272 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1273 {
1274 
1275 }
1276 
kvm_arch_flush_remote_tlbs_memslot(struct kvm * kvm,const struct kvm_memory_slot * memslot)1277 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
1278 					const struct kvm_memory_slot *memslot)
1279 {
1280 	kvm_flush_remote_tlbs(kvm);
1281 }
1282 
kvm_vm_ioctl_set_device_addr(struct kvm * kvm,struct kvm_arm_device_addr * dev_addr)1283 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1284 					struct kvm_arm_device_addr *dev_addr)
1285 {
1286 	unsigned long dev_id, type;
1287 
1288 	dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >>
1289 		KVM_ARM_DEVICE_ID_SHIFT;
1290 	type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >>
1291 		KVM_ARM_DEVICE_TYPE_SHIFT;
1292 
1293 	switch (dev_id) {
1294 	case KVM_ARM_DEVICE_VGIC_V2:
1295 		if (!vgic_present)
1296 			return -ENXIO;
1297 		return kvm_vgic_addr(kvm, type, &dev_addr->addr, true);
1298 	default:
1299 		return -ENODEV;
1300 	}
1301 }
1302 
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1303 long kvm_arch_vm_ioctl(struct file *filp,
1304 		       unsigned int ioctl, unsigned long arg)
1305 {
1306 	struct kvm *kvm = filp->private_data;
1307 	void __user *argp = (void __user *)arg;
1308 
1309 	switch (ioctl) {
1310 	case KVM_CREATE_IRQCHIP: {
1311 		int ret;
1312 		if (!vgic_present)
1313 			return -ENXIO;
1314 		mutex_lock(&kvm->lock);
1315 		ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1316 		mutex_unlock(&kvm->lock);
1317 		return ret;
1318 	}
1319 	case KVM_ARM_SET_DEVICE_ADDR: {
1320 		struct kvm_arm_device_addr dev_addr;
1321 
1322 		if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1323 			return -EFAULT;
1324 		return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1325 	}
1326 	case KVM_ARM_PREFERRED_TARGET: {
1327 		int err;
1328 		struct kvm_vcpu_init init;
1329 
1330 		err = kvm_vcpu_preferred_target(&init);
1331 		if (err)
1332 			return err;
1333 
1334 		if (copy_to_user(argp, &init, sizeof(init)))
1335 			return -EFAULT;
1336 
1337 		return 0;
1338 	}
1339 	default:
1340 		return -EINVAL;
1341 	}
1342 }
1343 
nvhe_percpu_size(void)1344 static unsigned long nvhe_percpu_size(void)
1345 {
1346 	return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1347 		(unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1348 }
1349 
nvhe_percpu_order(void)1350 static unsigned long nvhe_percpu_order(void)
1351 {
1352 	unsigned long size = nvhe_percpu_size();
1353 
1354 	return size ? get_order(size) : 0;
1355 }
1356 
1357 /* A lookup table holding the hypervisor VA for each vector slot */
1358 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1359 
kvm_init_vector_slot(void * base,enum arm64_hyp_spectre_vector slot)1360 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1361 {
1362 	hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1363 }
1364 
kvm_init_vector_slots(void)1365 static int kvm_init_vector_slots(void)
1366 {
1367 	int err;
1368 	void *base;
1369 
1370 	base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1371 	kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1372 
1373 	base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1374 	kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1375 
1376 	if (!cpus_have_const_cap(ARM64_SPECTRE_V3A))
1377 		return 0;
1378 
1379 	if (!has_vhe()) {
1380 		err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1381 					       __BP_HARDEN_HYP_VECS_SZ, &base);
1382 		if (err)
1383 			return err;
1384 	}
1385 
1386 	kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1387 	kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1388 	return 0;
1389 }
1390 
cpu_prepare_hyp_mode(int cpu)1391 static void cpu_prepare_hyp_mode(int cpu)
1392 {
1393 	struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
1394 	unsigned long tcr;
1395 
1396 	/*
1397 	 * Calculate the raw per-cpu offset without a translation from the
1398 	 * kernel's mapping to the linear mapping, and store it in tpidr_el2
1399 	 * so that we can use adr_l to access per-cpu variables in EL2.
1400 	 * Also drop the KASAN tag which gets in the way...
1401 	 */
1402 	params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
1403 			    (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
1404 
1405 	params->mair_el2 = read_sysreg(mair_el1);
1406 
1407 	/*
1408 	 * The ID map may be configured to use an extended virtual address
1409 	 * range. This is only the case if system RAM is out of range for the
1410 	 * currently configured page size and VA_BITS, in which case we will
1411 	 * also need the extended virtual range for the HYP ID map, or we won't
1412 	 * be able to enable the EL2 MMU.
1413 	 *
1414 	 * However, at EL2, there is only one TTBR register, and we can't switch
1415 	 * between translation tables *and* update TCR_EL2.T0SZ at the same
1416 	 * time. Bottom line: we need to use the extended range with *both* our
1417 	 * translation tables.
1418 	 *
1419 	 * So use the same T0SZ value we use for the ID map.
1420 	 */
1421 	tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1;
1422 	tcr &= ~TCR_T0SZ_MASK;
1423 	tcr |= (idmap_t0sz & GENMASK(TCR_TxSZ_WIDTH - 1, 0)) << TCR_T0SZ_OFFSET;
1424 	params->tcr_el2 = tcr;
1425 
1426 	params->stack_hyp_va = kern_hyp_va(per_cpu(kvm_arm_hyp_stack_page, cpu) + PAGE_SIZE);
1427 	params->pgd_pa = kvm_mmu_get_httbr();
1428 	if (is_protected_kvm_enabled())
1429 		params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
1430 	else
1431 		params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
1432 	params->vttbr = params->vtcr = 0;
1433 
1434 	/*
1435 	 * Flush the init params from the data cache because the struct will
1436 	 * be read while the MMU is off.
1437 	 */
1438 	kvm_flush_dcache_to_poc(params, sizeof(*params));
1439 }
1440 
hyp_install_host_vector(void)1441 static void hyp_install_host_vector(void)
1442 {
1443 	struct kvm_nvhe_init_params *params;
1444 	struct arm_smccc_res res;
1445 
1446 	/* Switch from the HYP stub to our own HYP init vector */
1447 	__hyp_set_vectors(kvm_get_idmap_vector());
1448 
1449 	/*
1450 	 * Call initialization code, and switch to the full blown HYP code.
1451 	 * If the cpucaps haven't been finalized yet, something has gone very
1452 	 * wrong, and hyp will crash and burn when it uses any
1453 	 * cpus_have_const_cap() wrapper.
1454 	 */
1455 	BUG_ON(!system_capabilities_finalized());
1456 	params = this_cpu_ptr_nvhe_sym(kvm_init_params);
1457 	arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
1458 	WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
1459 }
1460 
cpu_init_hyp_mode(void)1461 static void cpu_init_hyp_mode(void)
1462 {
1463 	hyp_install_host_vector();
1464 
1465 	/*
1466 	 * Disabling SSBD on a non-VHE system requires us to enable SSBS
1467 	 * at EL2.
1468 	 */
1469 	if (this_cpu_has_cap(ARM64_SSBS) &&
1470 	    arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
1471 		kvm_call_hyp_nvhe(__kvm_enable_ssbs);
1472 	}
1473 }
1474 
cpu_hyp_reset(void)1475 static void cpu_hyp_reset(void)
1476 {
1477 	if (!is_kernel_in_hyp_mode())
1478 		__hyp_reset_vectors();
1479 }
1480 
1481 /*
1482  * EL2 vectors can be mapped and rerouted in a number of ways,
1483  * depending on the kernel configuration and CPU present:
1484  *
1485  * - If the CPU is affected by Spectre-v2, the hardening sequence is
1486  *   placed in one of the vector slots, which is executed before jumping
1487  *   to the real vectors.
1488  *
1489  * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
1490  *   containing the hardening sequence is mapped next to the idmap page,
1491  *   and executed before jumping to the real vectors.
1492  *
1493  * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
1494  *   empty slot is selected, mapped next to the idmap page, and
1495  *   executed before jumping to the real vectors.
1496  *
1497  * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
1498  * VHE, as we don't have hypervisor-specific mappings. If the system
1499  * is VHE and yet selects this capability, it will be ignored.
1500  */
cpu_set_hyp_vector(void)1501 static void cpu_set_hyp_vector(void)
1502 {
1503 	struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
1504 	void *vector = hyp_spectre_vector_selector[data->slot];
1505 
1506 	if (!is_protected_kvm_enabled())
1507 		*this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
1508 	else
1509 		kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
1510 }
1511 
cpu_hyp_reinit(void)1512 static void cpu_hyp_reinit(void)
1513 {
1514 	kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt);
1515 
1516 	cpu_hyp_reset();
1517 
1518 	if (is_kernel_in_hyp_mode())
1519 		kvm_timer_init_vhe();
1520 	else
1521 		cpu_init_hyp_mode();
1522 
1523 	cpu_set_hyp_vector();
1524 
1525 	kvm_arm_init_debug();
1526 
1527 	if (vgic_present)
1528 		kvm_vgic_init_cpu_hardware();
1529 }
1530 
_kvm_arch_hardware_enable(void * discard)1531 static void _kvm_arch_hardware_enable(void *discard)
1532 {
1533 	if (!__this_cpu_read(kvm_arm_hardware_enabled)) {
1534 		cpu_hyp_reinit();
1535 		__this_cpu_write(kvm_arm_hardware_enabled, 1);
1536 	}
1537 }
1538 
kvm_arch_hardware_enable(void)1539 int kvm_arch_hardware_enable(void)
1540 {
1541 	_kvm_arch_hardware_enable(NULL);
1542 	return 0;
1543 }
1544 
_kvm_arch_hardware_disable(void * discard)1545 static void _kvm_arch_hardware_disable(void *discard)
1546 {
1547 	if (__this_cpu_read(kvm_arm_hardware_enabled)) {
1548 		cpu_hyp_reset();
1549 		__this_cpu_write(kvm_arm_hardware_enabled, 0);
1550 	}
1551 }
1552 
kvm_arch_hardware_disable(void)1553 void kvm_arch_hardware_disable(void)
1554 {
1555 	if (!is_protected_kvm_enabled())
1556 		_kvm_arch_hardware_disable(NULL);
1557 }
1558 
1559 #ifdef CONFIG_CPU_PM
hyp_init_cpu_pm_notifier(struct notifier_block * self,unsigned long cmd,void * v)1560 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
1561 				    unsigned long cmd,
1562 				    void *v)
1563 {
1564 	/*
1565 	 * kvm_arm_hardware_enabled is left with its old value over
1566 	 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
1567 	 * re-enable hyp.
1568 	 */
1569 	switch (cmd) {
1570 	case CPU_PM_ENTER:
1571 		if (__this_cpu_read(kvm_arm_hardware_enabled))
1572 			/*
1573 			 * don't update kvm_arm_hardware_enabled here
1574 			 * so that the hardware will be re-enabled
1575 			 * when we resume. See below.
1576 			 */
1577 			cpu_hyp_reset();
1578 
1579 		return NOTIFY_OK;
1580 	case CPU_PM_ENTER_FAILED:
1581 	case CPU_PM_EXIT:
1582 		if (__this_cpu_read(kvm_arm_hardware_enabled))
1583 			/* The hardware was enabled before suspend. */
1584 			cpu_hyp_reinit();
1585 
1586 		return NOTIFY_OK;
1587 
1588 	default:
1589 		return NOTIFY_DONE;
1590 	}
1591 }
1592 
1593 static struct notifier_block hyp_init_cpu_pm_nb = {
1594 	.notifier_call = hyp_init_cpu_pm_notifier,
1595 };
1596 
hyp_cpu_pm_init(void)1597 static void hyp_cpu_pm_init(void)
1598 {
1599 	if (!is_protected_kvm_enabled())
1600 		cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
1601 }
hyp_cpu_pm_exit(void)1602 static void hyp_cpu_pm_exit(void)
1603 {
1604 	if (!is_protected_kvm_enabled())
1605 		cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
1606 }
1607 #else
hyp_cpu_pm_init(void)1608 static inline void hyp_cpu_pm_init(void)
1609 {
1610 }
hyp_cpu_pm_exit(void)1611 static inline void hyp_cpu_pm_exit(void)
1612 {
1613 }
1614 #endif
1615 
init_cpu_logical_map(void)1616 static void init_cpu_logical_map(void)
1617 {
1618 	unsigned int cpu;
1619 
1620 	/*
1621 	 * Copy the MPIDR <-> logical CPU ID mapping to hyp.
1622 	 * Only copy the set of online CPUs whose features have been chacked
1623 	 * against the finalized system capabilities. The hypervisor will not
1624 	 * allow any other CPUs from the `possible` set to boot.
1625 	 */
1626 	for_each_online_cpu(cpu)
1627 		hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
1628 }
1629 
1630 #define init_psci_0_1_impl_state(config, what)	\
1631 	config.psci_0_1_ ## what ## _implemented = psci_ops.what
1632 
init_psci_relay(void)1633 static bool init_psci_relay(void)
1634 {
1635 	/*
1636 	 * If PSCI has not been initialized, protected KVM cannot install
1637 	 * itself on newly booted CPUs.
1638 	 */
1639 	if (!psci_ops.get_version) {
1640 		kvm_err("Cannot initialize protected mode without PSCI\n");
1641 		return false;
1642 	}
1643 
1644 	kvm_host_psci_config.version = psci_ops.get_version();
1645 
1646 	if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
1647 		kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
1648 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
1649 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
1650 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
1651 		init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
1652 	}
1653 	return true;
1654 }
1655 
init_common_resources(void)1656 static int init_common_resources(void)
1657 {
1658 	return kvm_set_ipa_limit();
1659 }
1660 
init_subsystems(void)1661 static int init_subsystems(void)
1662 {
1663 	int err = 0;
1664 
1665 	/*
1666 	 * Enable hardware so that subsystem initialisation can access EL2.
1667 	 */
1668 	on_each_cpu(_kvm_arch_hardware_enable, NULL, 1);
1669 
1670 	/*
1671 	 * Register CPU lower-power notifier
1672 	 */
1673 	hyp_cpu_pm_init();
1674 
1675 	/*
1676 	 * Init HYP view of VGIC
1677 	 */
1678 	err = kvm_vgic_hyp_init();
1679 	switch (err) {
1680 	case 0:
1681 		vgic_present = true;
1682 		break;
1683 	case -ENODEV:
1684 	case -ENXIO:
1685 		vgic_present = false;
1686 		err = 0;
1687 		break;
1688 	default:
1689 		goto out;
1690 	}
1691 
1692 	/*
1693 	 * Init HYP architected timer support
1694 	 */
1695 	err = kvm_timer_hyp_init(vgic_present);
1696 	if (err)
1697 		goto out;
1698 
1699 	kvm_perf_init();
1700 	kvm_sys_reg_table_init();
1701 
1702 out:
1703 	if (err || !is_protected_kvm_enabled())
1704 		on_each_cpu(_kvm_arch_hardware_disable, NULL, 1);
1705 
1706 	return err;
1707 }
1708 
teardown_hyp_mode(void)1709 static void teardown_hyp_mode(void)
1710 {
1711 	int cpu;
1712 
1713 	free_hyp_pgds();
1714 	for_each_possible_cpu(cpu) {
1715 		free_page(per_cpu(kvm_arm_hyp_stack_page, cpu));
1716 		free_pages(kvm_arm_hyp_percpu_base[cpu], nvhe_percpu_order());
1717 	}
1718 }
1719 
do_pkvm_init(u32 hyp_va_bits)1720 static int do_pkvm_init(u32 hyp_va_bits)
1721 {
1722 	void *per_cpu_base = kvm_ksym_ref(kvm_arm_hyp_percpu_base);
1723 	int ret;
1724 
1725 	preempt_disable();
1726 	hyp_install_host_vector();
1727 	ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
1728 				num_possible_cpus(), kern_hyp_va(per_cpu_base),
1729 				hyp_va_bits);
1730 	preempt_enable();
1731 
1732 	return ret;
1733 }
1734 
kvm_hyp_init_protection(u32 hyp_va_bits)1735 static int kvm_hyp_init_protection(u32 hyp_va_bits)
1736 {
1737 	void *addr = phys_to_virt(hyp_mem_base);
1738 	int ret;
1739 
1740 	kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
1741 	kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
1742 
1743 	ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
1744 	if (ret)
1745 		return ret;
1746 
1747 	ret = do_pkvm_init(hyp_va_bits);
1748 	if (ret)
1749 		return ret;
1750 
1751 	free_hyp_pgds();
1752 
1753 	return 0;
1754 }
1755 
1756 /**
1757  * Inits Hyp-mode on all online CPUs
1758  */
init_hyp_mode(void)1759 static int init_hyp_mode(void)
1760 {
1761 	u32 hyp_va_bits;
1762 	int cpu;
1763 	int err = -ENOMEM;
1764 
1765 	/*
1766 	 * The protected Hyp-mode cannot be initialized if the memory pool
1767 	 * allocation has failed.
1768 	 */
1769 	if (is_protected_kvm_enabled() && !hyp_mem_base)
1770 		goto out_err;
1771 
1772 	/*
1773 	 * Allocate Hyp PGD and setup Hyp identity mapping
1774 	 */
1775 	err = kvm_mmu_init(&hyp_va_bits);
1776 	if (err)
1777 		goto out_err;
1778 
1779 	/*
1780 	 * Allocate stack pages for Hypervisor-mode
1781 	 */
1782 	for_each_possible_cpu(cpu) {
1783 		unsigned long stack_page;
1784 
1785 		stack_page = __get_free_page(GFP_KERNEL);
1786 		if (!stack_page) {
1787 			err = -ENOMEM;
1788 			goto out_err;
1789 		}
1790 
1791 		per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page;
1792 	}
1793 
1794 	/*
1795 	 * Allocate and initialize pages for Hypervisor-mode percpu regions.
1796 	 */
1797 	for_each_possible_cpu(cpu) {
1798 		struct page *page;
1799 		void *page_addr;
1800 
1801 		page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
1802 		if (!page) {
1803 			err = -ENOMEM;
1804 			goto out_err;
1805 		}
1806 
1807 		page_addr = page_address(page);
1808 		memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
1809 		kvm_arm_hyp_percpu_base[cpu] = (unsigned long)page_addr;
1810 	}
1811 
1812 	/*
1813 	 * Map the Hyp-code called directly from the host
1814 	 */
1815 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
1816 				  kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
1817 	if (err) {
1818 		kvm_err("Cannot map world-switch code\n");
1819 		goto out_err;
1820 	}
1821 
1822 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
1823 				  kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
1824 	if (err) {
1825 		kvm_err("Cannot map .hyp.rodata section\n");
1826 		goto out_err;
1827 	}
1828 
1829 	err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
1830 				  kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
1831 	if (err) {
1832 		kvm_err("Cannot map rodata section\n");
1833 		goto out_err;
1834 	}
1835 
1836 	/*
1837 	 * .hyp.bss is guaranteed to be placed at the beginning of the .bss
1838 	 * section thanks to an assertion in the linker script. Map it RW and
1839 	 * the rest of .bss RO.
1840 	 */
1841 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
1842 				  kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
1843 	if (err) {
1844 		kvm_err("Cannot map hyp bss section: %d\n", err);
1845 		goto out_err;
1846 	}
1847 
1848 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
1849 				  kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
1850 	if (err) {
1851 		kvm_err("Cannot map bss section\n");
1852 		goto out_err;
1853 	}
1854 
1855 	/*
1856 	 * Map the Hyp stack pages
1857 	 */
1858 	for_each_possible_cpu(cpu) {
1859 		char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu);
1860 		err = create_hyp_mappings(stack_page, stack_page + PAGE_SIZE,
1861 					  PAGE_HYP);
1862 
1863 		if (err) {
1864 			kvm_err("Cannot map hyp stack\n");
1865 			goto out_err;
1866 		}
1867 	}
1868 
1869 	for_each_possible_cpu(cpu) {
1870 		char *percpu_begin = (char *)kvm_arm_hyp_percpu_base[cpu];
1871 		char *percpu_end = percpu_begin + nvhe_percpu_size();
1872 
1873 		/* Map Hyp percpu pages */
1874 		err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
1875 		if (err) {
1876 			kvm_err("Cannot map hyp percpu region\n");
1877 			goto out_err;
1878 		}
1879 
1880 		/* Prepare the CPU initialization parameters */
1881 		cpu_prepare_hyp_mode(cpu);
1882 	}
1883 
1884 	if (is_protected_kvm_enabled()) {
1885 		init_cpu_logical_map();
1886 
1887 		if (!init_psci_relay()) {
1888 			err = -ENODEV;
1889 			goto out_err;
1890 		}
1891 	}
1892 
1893 	if (is_protected_kvm_enabled()) {
1894 		err = kvm_hyp_init_protection(hyp_va_bits);
1895 		if (err) {
1896 			kvm_err("Failed to init hyp memory protection\n");
1897 			goto out_err;
1898 		}
1899 	}
1900 
1901 	return 0;
1902 
1903 out_err:
1904 	teardown_hyp_mode();
1905 	kvm_err("error initializing Hyp mode: %d\n", err);
1906 	return err;
1907 }
1908 
_kvm_host_prot_finalize(void * discard)1909 static void _kvm_host_prot_finalize(void *discard)
1910 {
1911 	WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize));
1912 }
1913 
pkvm_mark_hyp(phys_addr_t start,phys_addr_t end)1914 static inline int pkvm_mark_hyp(phys_addr_t start, phys_addr_t end)
1915 {
1916 	return kvm_call_hyp_nvhe(__pkvm_mark_hyp, start, end);
1917 }
1918 
1919 #define pkvm_mark_hyp_section(__section)		\
1920 	pkvm_mark_hyp(__pa_symbol(__section##_start),	\
1921 			__pa_symbol(__section##_end))
1922 
finalize_hyp_mode(void)1923 static int finalize_hyp_mode(void)
1924 {
1925 	int cpu, ret;
1926 
1927 	if (!is_protected_kvm_enabled())
1928 		return 0;
1929 
1930 	ret = pkvm_mark_hyp_section(__hyp_idmap_text);
1931 	if (ret)
1932 		return ret;
1933 
1934 	ret = pkvm_mark_hyp_section(__hyp_text);
1935 	if (ret)
1936 		return ret;
1937 
1938 	ret = pkvm_mark_hyp_section(__hyp_rodata);
1939 	if (ret)
1940 		return ret;
1941 
1942 	ret = pkvm_mark_hyp_section(__hyp_bss);
1943 	if (ret)
1944 		return ret;
1945 
1946 	ret = pkvm_mark_hyp(hyp_mem_base, hyp_mem_base + hyp_mem_size);
1947 	if (ret)
1948 		return ret;
1949 
1950 	for_each_possible_cpu(cpu) {
1951 		phys_addr_t start = virt_to_phys((void *)kvm_arm_hyp_percpu_base[cpu]);
1952 		phys_addr_t end = start + (PAGE_SIZE << nvhe_percpu_order());
1953 
1954 		ret = pkvm_mark_hyp(start, end);
1955 		if (ret)
1956 			return ret;
1957 
1958 		start = virt_to_phys((void *)per_cpu(kvm_arm_hyp_stack_page, cpu));
1959 		end = start + PAGE_SIZE;
1960 		ret = pkvm_mark_hyp(start, end);
1961 		if (ret)
1962 			return ret;
1963 	}
1964 
1965 	/*
1966 	 * Flip the static key upfront as that may no longer be possible
1967 	 * once the host stage 2 is installed.
1968 	 */
1969 	static_branch_enable(&kvm_protected_mode_initialized);
1970 	on_each_cpu(_kvm_host_prot_finalize, NULL, 1);
1971 
1972 	return 0;
1973 }
1974 
check_kvm_target_cpu(void * ret)1975 static void check_kvm_target_cpu(void *ret)
1976 {
1977 	*(int *)ret = kvm_target_cpu();
1978 }
1979 
kvm_mpidr_to_vcpu(struct kvm * kvm,unsigned long mpidr)1980 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
1981 {
1982 	struct kvm_vcpu *vcpu;
1983 	int i;
1984 
1985 	mpidr &= MPIDR_HWID_BITMASK;
1986 	kvm_for_each_vcpu(i, vcpu, kvm) {
1987 		if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
1988 			return vcpu;
1989 	}
1990 	return NULL;
1991 }
1992 
kvm_arch_has_irq_bypass(void)1993 bool kvm_arch_has_irq_bypass(void)
1994 {
1995 	return true;
1996 }
1997 
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)1998 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
1999 				      struct irq_bypass_producer *prod)
2000 {
2001 	struct kvm_kernel_irqfd *irqfd =
2002 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2003 
2004 	return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2005 					  &irqfd->irq_entry);
2006 }
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2007 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2008 				      struct irq_bypass_producer *prod)
2009 {
2010 	struct kvm_kernel_irqfd *irqfd =
2011 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2012 
2013 	kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
2014 				     &irqfd->irq_entry);
2015 }
2016 
kvm_arch_irq_bypass_stop(struct irq_bypass_consumer * cons)2017 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
2018 {
2019 	struct kvm_kernel_irqfd *irqfd =
2020 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2021 
2022 	kvm_arm_halt_guest(irqfd->kvm);
2023 }
2024 
kvm_arch_irq_bypass_start(struct irq_bypass_consumer * cons)2025 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
2026 {
2027 	struct kvm_kernel_irqfd *irqfd =
2028 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2029 
2030 	kvm_arm_resume_guest(irqfd->kvm);
2031 }
2032 
2033 /**
2034  * Initialize Hyp-mode and memory mappings on all CPUs.
2035  */
kvm_arch_init(void * opaque)2036 int kvm_arch_init(void *opaque)
2037 {
2038 	int err;
2039 	int ret, cpu;
2040 	bool in_hyp_mode;
2041 
2042 	if (!is_hyp_mode_available()) {
2043 		kvm_info("HYP mode not available\n");
2044 		return -ENODEV;
2045 	}
2046 
2047 	in_hyp_mode = is_kernel_in_hyp_mode();
2048 
2049 	if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2050 	    cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2051 		kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2052 			 "Only trusted guests should be used on this system.\n");
2053 
2054 	for_each_online_cpu(cpu) {
2055 		smp_call_function_single(cpu, check_kvm_target_cpu, &ret, 1);
2056 		if (ret < 0) {
2057 			kvm_err("Error, CPU %d not supported!\n", cpu);
2058 			return -ENODEV;
2059 		}
2060 	}
2061 
2062 	err = init_common_resources();
2063 	if (err)
2064 		return err;
2065 
2066 	err = kvm_arm_init_sve();
2067 	if (err)
2068 		return err;
2069 
2070 	if (!in_hyp_mode) {
2071 		err = init_hyp_mode();
2072 		if (err)
2073 			goto out_err;
2074 	}
2075 
2076 	err = kvm_init_vector_slots();
2077 	if (err) {
2078 		kvm_err("Cannot initialise vector slots\n");
2079 		goto out_err;
2080 	}
2081 
2082 	err = init_subsystems();
2083 	if (err)
2084 		goto out_hyp;
2085 
2086 	if (!in_hyp_mode) {
2087 		err = finalize_hyp_mode();
2088 		if (err) {
2089 			kvm_err("Failed to finalize Hyp protection\n");
2090 			goto out_hyp;
2091 		}
2092 	}
2093 
2094 	if (is_protected_kvm_enabled()) {
2095 		kvm_info("Protected nVHE mode initialized successfully\n");
2096 	} else if (in_hyp_mode) {
2097 		kvm_info("VHE mode initialized successfully\n");
2098 	} else {
2099 		kvm_info("Hyp mode initialized successfully\n");
2100 	}
2101 
2102 	return 0;
2103 
2104 out_hyp:
2105 	hyp_cpu_pm_exit();
2106 	if (!in_hyp_mode)
2107 		teardown_hyp_mode();
2108 out_err:
2109 	return err;
2110 }
2111 
2112 /* NOP: Compiling as a module not supported */
kvm_arch_exit(void)2113 void kvm_arch_exit(void)
2114 {
2115 	kvm_perf_teardown();
2116 }
2117 
early_kvm_mode_cfg(char * arg)2118 static int __init early_kvm_mode_cfg(char *arg)
2119 {
2120 	if (!arg)
2121 		return -EINVAL;
2122 
2123 	if (strcmp(arg, "protected") == 0) {
2124 		kvm_mode = KVM_MODE_PROTECTED;
2125 		return 0;
2126 	}
2127 
2128 	if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode()))
2129 		return 0;
2130 
2131 	return -EINVAL;
2132 }
2133 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2134 
kvm_get_mode(void)2135 enum kvm_mode kvm_get_mode(void)
2136 {
2137 	return kvm_mode;
2138 }
2139 
arm_init(void)2140 static int arm_init(void)
2141 {
2142 	int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2143 	return rc;
2144 }
2145 
2146 module_init(arm_init);
2147