xref: /freebsd/sys/i386/i386/machdep.c (revision 5f757f3f)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 2018 The FreeBSD Foundation
5  * Copyright (c) 1992 Terrence R. Lambert.
6  * Copyright (c) 1982, 1987, 1990 The Regents of the University of California.
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * William Jolitz.
11  *
12  * Portions of this software were developed by A. Joseph Koshy under
13  * sponsorship from the FreeBSD Foundation and Google, Inc.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  * 3. All advertising materials mentioning features or use of this software
24  *    must display the following acknowledgement:
25  *	This product includes software developed by the University of
26  *	California, Berkeley and its contributors.
27  * 4. Neither the name of the University nor the names of its contributors
28  *    may be used to endorse or promote products derived from this software
29  *    without specific prior written permission.
30  *
31  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
32  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
33  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
35  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
39  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
40  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
41  * SUCH DAMAGE.
42  */
43 
44 #include <sys/cdefs.h>
45 #include "opt_apic.h"
46 #include "opt_atpic.h"
47 #include "opt_cpu.h"
48 #include "opt_ddb.h"
49 #include "opt_inet.h"
50 #include "opt_isa.h"
51 #include "opt_kstack_pages.h"
52 #include "opt_maxmem.h"
53 #include "opt_perfmon.h"
54 #include "opt_platform.h"
55 
56 #include <sys/param.h>
57 #include <sys/proc.h>
58 #include <sys/systm.h>
59 #include <sys/bio.h>
60 #include <sys/buf.h>
61 #include <sys/bus.h>
62 #include <sys/callout.h>
63 #include <sys/cons.h>
64 #include <sys/cpu.h>
65 #include <sys/eventhandler.h>
66 #include <sys/exec.h>
67 #include <sys/imgact.h>
68 #include <sys/kdb.h>
69 #include <sys/kernel.h>
70 #include <sys/ktr.h>
71 #include <sys/linker.h>
72 #include <sys/lock.h>
73 #include <sys/malloc.h>
74 #include <sys/memrange.h>
75 #include <sys/msgbuf.h>
76 #include <sys/mutex.h>
77 #include <sys/pcpu.h>
78 #include <sys/ptrace.h>
79 #include <sys/reboot.h>
80 #include <sys/reg.h>
81 #include <sys/rwlock.h>
82 #include <sys/sched.h>
83 #include <sys/signalvar.h>
84 #include <sys/smp.h>
85 #include <sys/syscallsubr.h>
86 #include <sys/sysctl.h>
87 #include <sys/sysent.h>
88 #include <sys/sysproto.h>
89 #include <sys/ucontext.h>
90 #include <sys/vmmeter.h>
91 
92 #include <vm/vm.h>
93 #include <vm/vm_param.h>
94 #include <vm/vm_extern.h>
95 #include <vm/vm_kern.h>
96 #include <vm/vm_page.h>
97 #include <vm/vm_map.h>
98 #include <vm/vm_object.h>
99 #include <vm/vm_pager.h>
100 #include <vm/vm_phys.h>
101 #include <vm/vm_dumpset.h>
102 
103 #ifdef DDB
104 #ifndef KDB
105 #error KDB must be enabled in order for DDB to work!
106 #endif
107 #include <ddb/ddb.h>
108 #include <ddb/db_sym.h>
109 #endif
110 
111 #include <isa/rtc.h>
112 
113 #include <net/netisr.h>
114 
115 #include <dev/smbios/smbios.h>
116 
117 #include <machine/bootinfo.h>
118 #include <machine/clock.h>
119 #include <machine/cpu.h>
120 #include <machine/cputypes.h>
121 #include <machine/intr_machdep.h>
122 #include <x86/mca.h>
123 #include <machine/md_var.h>
124 #include <machine/metadata.h>
125 #include <machine/pc/bios.h>
126 #include <machine/pcb.h>
127 #include <machine/pcb_ext.h>
128 #include <machine/proc.h>
129 #include <machine/sigframe.h>
130 #include <machine/specialreg.h>
131 #include <machine/sysarch.h>
132 #include <machine/trap.h>
133 #include <x86/ucode.h>
134 #include <machine/vm86.h>
135 #include <x86/init.h>
136 #ifdef PERFMON
137 #include <machine/perfmon.h>
138 #endif
139 #ifdef SMP
140 #include <machine/smp.h>
141 #endif
142 #ifdef FDT
143 #include <x86/fdt.h>
144 #endif
145 
146 #ifdef DEV_APIC
147 #include <x86/apicvar.h>
148 #endif
149 
150 #ifdef DEV_ISA
151 #include <x86/isa/icu.h>
152 #endif
153 
154 /* Sanity check for __curthread() */
155 CTASSERT(offsetof(struct pcpu, pc_curthread) == 0);
156 
157 register_t init386(int first);
158 void dblfault_handler(void);
159 void identify_cpu(void);
160 
161 static void cpu_startup(void *);
162 SYSINIT(cpu, SI_SUB_CPU, SI_ORDER_FIRST, cpu_startup, NULL);
163 
164 /* Intel ICH registers */
165 #define ICH_PMBASE	0x400
166 #define ICH_SMI_EN	ICH_PMBASE + 0x30
167 
168 int	_udatasel, _ucodesel;
169 u_int	basemem;
170 static int above4g_allow = 1;
171 static int above24g_allow = 0;
172 
173 int cold = 1;
174 
175 long Maxmem = 0;
176 long realmem = 0;
177 int late_console = 1;
178 
179 #ifdef PAE
180 FEATURE(pae, "Physical Address Extensions");
181 #endif
182 
183 struct kva_md_info kmi;
184 
185 static struct trapframe proc0_tf;
186 struct pcpu __pcpu[MAXCPU];
187 
188 static void i386_clock_source_init(void);
189 
190 struct mtx icu_lock;
191 
192 struct mem_range_softc mem_range_softc;
193 
194 extern char start_exceptions[], end_exceptions[];
195 
196 extern struct sysentvec elf32_freebsd_sysvec;
197 
198 /* Default init_ops implementation. */
199 struct init_ops init_ops = {
200 	.early_clock_source_init =	i386_clock_source_init,
201 	.early_delay =			i8254_delay,
202 };
203 
204 static void
205 i386_clock_source_init(void)
206 {
207 	i8254_init();
208 }
209 
210 static void
211 cpu_startup(void *dummy)
212 {
213 	uintmax_t memsize;
214 	char *sysenv;
215 
216 	/*
217 	 * On MacBooks, we need to disallow the legacy USB circuit to
218 	 * generate an SMI# because this can cause several problems,
219 	 * namely: incorrect CPU frequency detection and failure to
220 	 * start the APs.
221 	 * We do this by disabling a bit in the SMI_EN (SMI Control and
222 	 * Enable register) of the Intel ICH LPC Interface Bridge.
223 	 */
224 	sysenv = kern_getenv("smbios.system.product");
225 	if (sysenv != NULL) {
226 		if (strncmp(sysenv, "MacBook1,1", 10) == 0 ||
227 		    strncmp(sysenv, "MacBook3,1", 10) == 0 ||
228 		    strncmp(sysenv, "MacBook4,1", 10) == 0 ||
229 		    strncmp(sysenv, "MacBookPro1,1", 13) == 0 ||
230 		    strncmp(sysenv, "MacBookPro1,2", 13) == 0 ||
231 		    strncmp(sysenv, "MacBookPro3,1", 13) == 0 ||
232 		    strncmp(sysenv, "MacBookPro4,1", 13) == 0 ||
233 		    strncmp(sysenv, "Macmini1,1", 10) == 0) {
234 			if (bootverbose)
235 				printf("Disabling LEGACY_USB_EN bit on "
236 				    "Intel ICH.\n");
237 			outl(ICH_SMI_EN, inl(ICH_SMI_EN) & ~0x8);
238 		}
239 		freeenv(sysenv);
240 	}
241 
242 	/*
243 	 * Good {morning,afternoon,evening,night}.
244 	 */
245 	startrtclock();
246 	printcpuinfo();
247 	panicifcpuunsupported();
248 #ifdef PERFMON
249 	perfmon_init();
250 #endif
251 
252 	/*
253 	 * Display physical memory if SMBIOS reports reasonable amount.
254 	 */
255 	memsize = 0;
256 	sysenv = kern_getenv("smbios.memory.enabled");
257 	if (sysenv != NULL) {
258 		memsize = (uintmax_t)strtoul(sysenv, (char **)NULL, 10) << 10;
259 		freeenv(sysenv);
260 	}
261 	if (memsize < ptoa((uintmax_t)vm_free_count()))
262 		memsize = ptoa((uintmax_t)Maxmem);
263 	printf("real memory  = %ju (%ju MB)\n", memsize, memsize >> 20);
264 	realmem = atop(memsize);
265 
266 	/*
267 	 * Display any holes after the first chunk of extended memory.
268 	 */
269 	if (bootverbose) {
270 		int indx;
271 
272 		printf("Physical memory chunk(s):\n");
273 		for (indx = 0; phys_avail[indx + 1] != 0; indx += 2) {
274 			vm_paddr_t size;
275 
276 			size = phys_avail[indx + 1] - phys_avail[indx];
277 			printf(
278 			    "0x%016jx - 0x%016jx, %ju bytes (%ju pages)\n",
279 			    (uintmax_t)phys_avail[indx],
280 			    (uintmax_t)phys_avail[indx + 1] - 1,
281 			    (uintmax_t)size, (uintmax_t)size / PAGE_SIZE);
282 		}
283 	}
284 
285 	vm_ksubmap_init(&kmi);
286 
287 	printf("avail memory = %ju (%ju MB)\n",
288 	    ptoa((uintmax_t)vm_free_count()),
289 	    ptoa((uintmax_t)vm_free_count()) / 1048576);
290 
291 	/*
292 	 * Set up buffers, so they can be used to read disk labels.
293 	 */
294 	bufinit();
295 	vm_pager_bufferinit();
296 	cpu_setregs();
297 }
298 
299 void
300 cpu_setregs(void)
301 {
302 	unsigned int cr0;
303 
304 	cr0 = rcr0();
305 
306 	/*
307 	 * CR0_MP, CR0_NE and CR0_TS are set for NPX (FPU) support:
308 	 *
309 	 * Prepare to trap all ESC (i.e., NPX) instructions and all WAIT
310 	 * instructions.  We must set the CR0_MP bit and use the CR0_TS
311 	 * bit to control the trap, because setting the CR0_EM bit does
312 	 * not cause WAIT instructions to trap.  It's important to trap
313 	 * WAIT instructions - otherwise the "wait" variants of no-wait
314 	 * control instructions would degenerate to the "no-wait" variants
315 	 * after FP context switches but work correctly otherwise.  It's
316 	 * particularly important to trap WAITs when there is no NPX -
317 	 * otherwise the "wait" variants would always degenerate.
318 	 *
319 	 * Try setting CR0_NE to get correct error reporting on 486DX's.
320 	 * Setting it should fail or do nothing on lesser processors.
321 	 */
322 	cr0 |= CR0_MP | CR0_NE | CR0_TS | CR0_WP | CR0_AM;
323 	load_cr0(cr0);
324 	load_gs(_udatasel);
325 }
326 
327 u_long bootdev;		/* not a struct cdev *- encoding is different */
328 SYSCTL_ULONG(_machdep, OID_AUTO, guessed_bootdev,
329 	CTLFLAG_RD, &bootdev, 0, "Maybe the Boot device (not in struct cdev *format)");
330 
331 /*
332  * Initialize 386 and configure to run kernel
333  */
334 
335 /*
336  * Initialize segments & interrupt table
337  */
338 
339 int _default_ldt;
340 
341 struct mtx dt_lock;			/* lock for GDT and LDT */
342 
343 union descriptor gdt0[NGDT];	/* initial global descriptor table */
344 union descriptor *gdt = gdt0;	/* global descriptor table */
345 
346 union descriptor *ldt;		/* local descriptor table */
347 
348 static struct gate_descriptor idt0[NIDT];
349 struct gate_descriptor *idt = &idt0[0];	/* interrupt descriptor table */
350 
351 static struct i386tss *dblfault_tss;
352 static char *dblfault_stack;
353 
354 static struct i386tss common_tss0;
355 
356 vm_offset_t proc0kstack;
357 
358 /*
359  * software prototypes -- in more palatable form.
360  *
361  * GCODE_SEL through GUDATA_SEL must be in this order for syscall/sysret
362  * GUFS_SEL and GUGS_SEL must be in this order (swtch.s knows it)
363  */
364 struct soft_segment_descriptor gdt_segs[] = {
365 /* GNULL_SEL	0 Null Descriptor */
366 {	.ssd_base = 0x0,
367 	.ssd_limit = 0x0,
368 	.ssd_type = 0,
369 	.ssd_dpl = SEL_KPL,
370 	.ssd_p = 0,
371 	.ssd_xx = 0, .ssd_xx1 = 0,
372 	.ssd_def32 = 0,
373 	.ssd_gran = 0		},
374 /* GPRIV_SEL	1 SMP Per-Processor Private Data Descriptor */
375 {	.ssd_base = 0x0,
376 	.ssd_limit = 0xfffff,
377 	.ssd_type = SDT_MEMRWA,
378 	.ssd_dpl = SEL_KPL,
379 	.ssd_p = 1,
380 	.ssd_xx = 0, .ssd_xx1 = 0,
381 	.ssd_def32 = 1,
382 	.ssd_gran = 1		},
383 /* GUFS_SEL	2 %fs Descriptor for user */
384 {	.ssd_base = 0x0,
385 	.ssd_limit = 0xfffff,
386 	.ssd_type = SDT_MEMRWA,
387 	.ssd_dpl = SEL_UPL,
388 	.ssd_p = 1,
389 	.ssd_xx = 0, .ssd_xx1 = 0,
390 	.ssd_def32 = 1,
391 	.ssd_gran = 1		},
392 /* GUGS_SEL	3 %gs Descriptor for user */
393 {	.ssd_base = 0x0,
394 	.ssd_limit = 0xfffff,
395 	.ssd_type = SDT_MEMRWA,
396 	.ssd_dpl = SEL_UPL,
397 	.ssd_p = 1,
398 	.ssd_xx = 0, .ssd_xx1 = 0,
399 	.ssd_def32 = 1,
400 	.ssd_gran = 1		},
401 /* GCODE_SEL	4 Code Descriptor for kernel */
402 {	.ssd_base = 0x0,
403 	.ssd_limit = 0xfffff,
404 	.ssd_type = SDT_MEMERA,
405 	.ssd_dpl = SEL_KPL,
406 	.ssd_p = 1,
407 	.ssd_xx = 0, .ssd_xx1 = 0,
408 	.ssd_def32 = 1,
409 	.ssd_gran = 1		},
410 /* GDATA_SEL	5 Data Descriptor for kernel */
411 {	.ssd_base = 0x0,
412 	.ssd_limit = 0xfffff,
413 	.ssd_type = SDT_MEMRWA,
414 	.ssd_dpl = SEL_KPL,
415 	.ssd_p = 1,
416 	.ssd_xx = 0, .ssd_xx1 = 0,
417 	.ssd_def32 = 1,
418 	.ssd_gran = 1		},
419 /* GUCODE_SEL	6 Code Descriptor for user */
420 {	.ssd_base = 0x0,
421 	.ssd_limit = 0xfffff,
422 	.ssd_type = SDT_MEMERA,
423 	.ssd_dpl = SEL_UPL,
424 	.ssd_p = 1,
425 	.ssd_xx = 0, .ssd_xx1 = 0,
426 	.ssd_def32 = 1,
427 	.ssd_gran = 1		},
428 /* GUDATA_SEL	7 Data Descriptor for user */
429 {	.ssd_base = 0x0,
430 	.ssd_limit = 0xfffff,
431 	.ssd_type = SDT_MEMRWA,
432 	.ssd_dpl = SEL_UPL,
433 	.ssd_p = 1,
434 	.ssd_xx = 0, .ssd_xx1 = 0,
435 	.ssd_def32 = 1,
436 	.ssd_gran = 1		},
437 /* GBIOSLOWMEM_SEL 8 BIOS access to realmode segment 0x40, must be #8 in GDT */
438 {	.ssd_base = 0x400,
439 	.ssd_limit = 0xfffff,
440 	.ssd_type = SDT_MEMRWA,
441 	.ssd_dpl = SEL_KPL,
442 	.ssd_p = 1,
443 	.ssd_xx = 0, .ssd_xx1 = 0,
444 	.ssd_def32 = 1,
445 	.ssd_gran = 1		},
446 /* GPROC0_SEL	9 Proc 0 Tss Descriptor */
447 {
448 	.ssd_base = 0x0,
449 	.ssd_limit = sizeof(struct i386tss)-1,
450 	.ssd_type = SDT_SYS386TSS,
451 	.ssd_dpl = 0,
452 	.ssd_p = 1,
453 	.ssd_xx = 0, .ssd_xx1 = 0,
454 	.ssd_def32 = 0,
455 	.ssd_gran = 0		},
456 /* GLDT_SEL	10 LDT Descriptor */
457 {	.ssd_base = 0,
458 	.ssd_limit = sizeof(union descriptor) * NLDT - 1,
459 	.ssd_type = SDT_SYSLDT,
460 	.ssd_dpl = SEL_UPL,
461 	.ssd_p = 1,
462 	.ssd_xx = 0, .ssd_xx1 = 0,
463 	.ssd_def32 = 0,
464 	.ssd_gran = 0		},
465 /* GUSERLDT_SEL	11 User LDT Descriptor per process */
466 {	.ssd_base = 0,
467 	.ssd_limit = (512 * sizeof(union descriptor)-1),
468 	.ssd_type = SDT_SYSLDT,
469 	.ssd_dpl = 0,
470 	.ssd_p = 1,
471 	.ssd_xx = 0, .ssd_xx1 = 0,
472 	.ssd_def32 = 0,
473 	.ssd_gran = 0		},
474 /* GPANIC_SEL	12 Panic Tss Descriptor */
475 {	.ssd_base = 0,
476 	.ssd_limit = sizeof(struct i386tss)-1,
477 	.ssd_type = SDT_SYS386TSS,
478 	.ssd_dpl = 0,
479 	.ssd_p = 1,
480 	.ssd_xx = 0, .ssd_xx1 = 0,
481 	.ssd_def32 = 0,
482 	.ssd_gran = 0		},
483 /* GBIOSCODE32_SEL 13 BIOS 32-bit interface (32bit Code) */
484 {	.ssd_base = 0,
485 	.ssd_limit = 0xfffff,
486 	.ssd_type = SDT_MEMERA,
487 	.ssd_dpl = 0,
488 	.ssd_p = 1,
489 	.ssd_xx = 0, .ssd_xx1 = 0,
490 	.ssd_def32 = 0,
491 	.ssd_gran = 1		},
492 /* GBIOSCODE16_SEL 14 BIOS 32-bit interface (16bit Code) */
493 {	.ssd_base = 0,
494 	.ssd_limit = 0xfffff,
495 	.ssd_type = SDT_MEMERA,
496 	.ssd_dpl = 0,
497 	.ssd_p = 1,
498 	.ssd_xx = 0, .ssd_xx1 = 0,
499 	.ssd_def32 = 0,
500 	.ssd_gran = 1		},
501 /* GBIOSDATA_SEL 15 BIOS 32-bit interface (Data) */
502 {	.ssd_base = 0,
503 	.ssd_limit = 0xfffff,
504 	.ssd_type = SDT_MEMRWA,
505 	.ssd_dpl = 0,
506 	.ssd_p = 1,
507 	.ssd_xx = 0, .ssd_xx1 = 0,
508 	.ssd_def32 = 1,
509 	.ssd_gran = 1		},
510 /* GBIOSUTIL_SEL 16 BIOS 16-bit interface (Utility) */
511 {	.ssd_base = 0,
512 	.ssd_limit = 0xfffff,
513 	.ssd_type = SDT_MEMRWA,
514 	.ssd_dpl = 0,
515 	.ssd_p = 1,
516 	.ssd_xx = 0, .ssd_xx1 = 0,
517 	.ssd_def32 = 0,
518 	.ssd_gran = 1		},
519 /* GBIOSARGS_SEL 17 BIOS 16-bit interface (Arguments) */
520 {	.ssd_base = 0,
521 	.ssd_limit = 0xfffff,
522 	.ssd_type = SDT_MEMRWA,
523 	.ssd_dpl = 0,
524 	.ssd_p = 1,
525 	.ssd_xx = 0, .ssd_xx1 = 0,
526 	.ssd_def32 = 0,
527 	.ssd_gran = 1		},
528 /* GNDIS_SEL	18 NDIS Descriptor */
529 {	.ssd_base = 0x0,
530 	.ssd_limit = 0x0,
531 	.ssd_type = 0,
532 	.ssd_dpl = 0,
533 	.ssd_p = 0,
534 	.ssd_xx = 0, .ssd_xx1 = 0,
535 	.ssd_def32 = 0,
536 	.ssd_gran = 0		},
537 };
538 
539 static struct soft_segment_descriptor ldt_segs[] = {
540 	/* Null Descriptor - overwritten by call gate */
541 {	.ssd_base = 0x0,
542 	.ssd_limit = 0x0,
543 	.ssd_type = 0,
544 	.ssd_dpl = 0,
545 	.ssd_p = 0,
546 	.ssd_xx = 0, .ssd_xx1 = 0,
547 	.ssd_def32 = 0,
548 	.ssd_gran = 0		},
549 	/* Null Descriptor - overwritten by call gate */
550 {	.ssd_base = 0x0,
551 	.ssd_limit = 0x0,
552 	.ssd_type = 0,
553 	.ssd_dpl = 0,
554 	.ssd_p = 0,
555 	.ssd_xx = 0, .ssd_xx1 = 0,
556 	.ssd_def32 = 0,
557 	.ssd_gran = 0		},
558 	/* Null Descriptor - overwritten by call gate */
559 {	.ssd_base = 0x0,
560 	.ssd_limit = 0x0,
561 	.ssd_type = 0,
562 	.ssd_dpl = 0,
563 	.ssd_p = 0,
564 	.ssd_xx = 0, .ssd_xx1 = 0,
565 	.ssd_def32 = 0,
566 	.ssd_gran = 0		},
567 	/* Code Descriptor for user */
568 {	.ssd_base = 0x0,
569 	.ssd_limit = 0xfffff,
570 	.ssd_type = SDT_MEMERA,
571 	.ssd_dpl = SEL_UPL,
572 	.ssd_p = 1,
573 	.ssd_xx = 0, .ssd_xx1 = 0,
574 	.ssd_def32 = 1,
575 	.ssd_gran = 1		},
576 	/* Null Descriptor - overwritten by call gate */
577 {	.ssd_base = 0x0,
578 	.ssd_limit = 0x0,
579 	.ssd_type = 0,
580 	.ssd_dpl = 0,
581 	.ssd_p = 0,
582 	.ssd_xx = 0, .ssd_xx1 = 0,
583 	.ssd_def32 = 0,
584 	.ssd_gran = 0		},
585 	/* Data Descriptor for user */
586 {	.ssd_base = 0x0,
587 	.ssd_limit = 0xfffff,
588 	.ssd_type = SDT_MEMRWA,
589 	.ssd_dpl = SEL_UPL,
590 	.ssd_p = 1,
591 	.ssd_xx = 0, .ssd_xx1 = 0,
592 	.ssd_def32 = 1,
593 	.ssd_gran = 1		},
594 };
595 
596 size_t setidt_disp;
597 
598 void
599 setidt(int idx, inthand_t *func, int typ, int dpl, int selec)
600 {
601 	uintptr_t off;
602 
603 	off = func != NULL ? (uintptr_t)func + setidt_disp : 0;
604 	setidt_nodisp(idx, off, typ, dpl, selec);
605 }
606 
607 void
608 setidt_nodisp(int idx, uintptr_t off, int typ, int dpl, int selec)
609 {
610 	struct gate_descriptor *ip;
611 
612 	ip = idt + idx;
613 	ip->gd_looffset = off;
614 	ip->gd_selector = selec;
615 	ip->gd_stkcpy = 0;
616 	ip->gd_xx = 0;
617 	ip->gd_type = typ;
618 	ip->gd_dpl = dpl;
619 	ip->gd_p = 1;
620 	ip->gd_hioffset = ((u_int)off) >> 16 ;
621 }
622 
623 extern inthand_t
624 	IDTVEC(div), IDTVEC(dbg), IDTVEC(nmi), IDTVEC(bpt), IDTVEC(ofl),
625 	IDTVEC(bnd), IDTVEC(ill), IDTVEC(dna), IDTVEC(fpusegm),
626 	IDTVEC(tss), IDTVEC(missing), IDTVEC(stk), IDTVEC(prot),
627 	IDTVEC(page), IDTVEC(mchk), IDTVEC(rsvd), IDTVEC(fpu), IDTVEC(align),
628 	IDTVEC(xmm),
629 #ifdef KDTRACE_HOOKS
630 	IDTVEC(dtrace_ret),
631 #endif
632 #ifdef XENHVM
633 	IDTVEC(xen_intr_upcall),
634 #endif
635 	IDTVEC(int0x80_syscall);
636 
637 #ifdef DDB
638 /*
639  * Display the index and function name of any IDT entries that don't use
640  * the default 'rsvd' entry point.
641  */
642 DB_SHOW_COMMAND_FLAGS(idt, db_show_idt, DB_CMD_MEMSAFE)
643 {
644 	struct gate_descriptor *ip;
645 	int idx;
646 	uintptr_t func, func_trm;
647 	bool trm;
648 
649 	ip = idt;
650 	for (idx = 0; idx < NIDT && !db_pager_quit; idx++) {
651 		if (ip->gd_type == SDT_SYSTASKGT) {
652 			db_printf("%3d\t<TASK>\n", idx);
653 		} else {
654 			func = (ip->gd_hioffset << 16 | ip->gd_looffset);
655 			if (func >= PMAP_TRM_MIN_ADDRESS) {
656 				func_trm = func;
657 				func -= setidt_disp;
658 				trm = true;
659 			} else
660 				trm = false;
661 			if (func != (uintptr_t)&IDTVEC(rsvd)) {
662 				db_printf("%3d\t", idx);
663 				db_printsym(func, DB_STGY_PROC);
664 				if (trm)
665 					db_printf(" (trampoline %#x)",
666 					    func_trm);
667 				db_printf("\n");
668 			}
669 		}
670 		ip++;
671 	}
672 }
673 
674 /* Show privileged registers. */
675 DB_SHOW_COMMAND_FLAGS(sysregs, db_show_sysregs, DB_CMD_MEMSAFE)
676 {
677 	uint64_t idtr, gdtr;
678 
679 	idtr = ridt();
680 	db_printf("idtr\t0x%08x/%04x\n",
681 	    (u_int)(idtr >> 16), (u_int)idtr & 0xffff);
682 	gdtr = rgdt();
683 	db_printf("gdtr\t0x%08x/%04x\n",
684 	    (u_int)(gdtr >> 16), (u_int)gdtr & 0xffff);
685 	db_printf("ldtr\t0x%04x\n", rldt());
686 	db_printf("tr\t0x%04x\n", rtr());
687 	db_printf("cr0\t0x%08x\n", rcr0());
688 	db_printf("cr2\t0x%08x\n", rcr2());
689 	db_printf("cr3\t0x%08x\n", rcr3());
690 	db_printf("cr4\t0x%08x\n", rcr4());
691 	if (rcr4() & CR4_XSAVE)
692 		db_printf("xcr0\t0x%016llx\n", rxcr(0));
693 	if (amd_feature & (AMDID_NX | AMDID_LM))
694 		db_printf("EFER\t0x%016llx\n", rdmsr(MSR_EFER));
695 	if (cpu_feature2 & (CPUID2_VMX | CPUID2_SMX))
696 		db_printf("FEATURES_CTL\t0x%016llx\n",
697 		    rdmsr(MSR_IA32_FEATURE_CONTROL));
698 	if (((cpu_vendor_id == CPU_VENDOR_INTEL ||
699 	    cpu_vendor_id == CPU_VENDOR_AMD) && CPUID_TO_FAMILY(cpu_id) >= 6) ||
700 	    cpu_vendor_id == CPU_VENDOR_HYGON)
701 		db_printf("DEBUG_CTL\t0x%016llx\n", rdmsr(MSR_DEBUGCTLMSR));
702 	if (cpu_feature & CPUID_PAT)
703 		db_printf("PAT\t0x%016llx\n", rdmsr(MSR_PAT));
704 }
705 
706 DB_SHOW_COMMAND_FLAGS(dbregs, db_show_dbregs, DB_CMD_MEMSAFE)
707 {
708 
709 	db_printf("dr0\t0x%08x\n", rdr0());
710 	db_printf("dr1\t0x%08x\n", rdr1());
711 	db_printf("dr2\t0x%08x\n", rdr2());
712 	db_printf("dr3\t0x%08x\n", rdr3());
713 	db_printf("dr6\t0x%08x\n", rdr6());
714 	db_printf("dr7\t0x%08x\n", rdr7());
715 }
716 
717 DB_SHOW_COMMAND(frame, db_show_frame)
718 {
719 	struct trapframe *frame;
720 
721 	frame = have_addr ? (struct trapframe *)addr : curthread->td_frame;
722 	printf("ss %#x esp %#x efl %#x cs %#x eip %#x\n",
723 	    frame->tf_ss, frame->tf_esp, frame->tf_eflags, frame->tf_cs,
724 	    frame->tf_eip);
725 	printf("err %#x trapno %d\n", frame->tf_err, frame->tf_trapno);
726 	printf("ds %#x es %#x fs %#x\n",
727 	    frame->tf_ds, frame->tf_es, frame->tf_fs);
728 	printf("eax %#x ecx %#x edx %#x ebx %#x\n",
729 	    frame->tf_eax, frame->tf_ecx, frame->tf_edx, frame->tf_ebx);
730 	printf("ebp %#x esi %#x edi %#x\n",
731 	    frame->tf_ebp, frame->tf_esi, frame->tf_edi);
732 
733 }
734 #endif
735 
736 void
737 sdtossd(struct segment_descriptor *sd, struct soft_segment_descriptor *ssd)
738 {
739 	ssd->ssd_base  = (sd->sd_hibase << 24) | sd->sd_lobase;
740 	ssd->ssd_limit = (sd->sd_hilimit << 16) | sd->sd_lolimit;
741 	ssd->ssd_type  = sd->sd_type;
742 	ssd->ssd_dpl   = sd->sd_dpl;
743 	ssd->ssd_p     = sd->sd_p;
744 	ssd->ssd_def32 = sd->sd_def32;
745 	ssd->ssd_gran  = sd->sd_gran;
746 }
747 
748 static int
749 add_physmap_entry(uint64_t base, uint64_t length, vm_paddr_t *physmap,
750     int *physmap_idxp)
751 {
752 	uint64_t lim, ign;
753 	int i, insert_idx, physmap_idx;
754 
755 	physmap_idx = *physmap_idxp;
756 
757 	if (length == 0)
758 		return (1);
759 
760 	lim = 0x100000000;					/*  4G */
761 	if (pae_mode && above4g_allow)
762 		lim = above24g_allow ? -1ULL : 0x600000000;	/* 24G */
763 	if (base >= lim) {
764 		printf("%uK of memory above %uGB ignored, pae %d "
765 		    "above4g_allow %d above24g_allow %d\n",
766 		    (u_int)(length / 1024), (u_int)(lim >> 30), pae_mode,
767 		    above4g_allow, above24g_allow);
768 		return (1);
769 	}
770 	if (base + length >= lim) {
771 		ign = base + length - lim;
772 		length -= ign;
773 		printf("%uK of memory above %uGB ignored, pae %d "
774 		    "above4g_allow %d above24g_allow %d\n",
775 		    (u_int)(ign / 1024), (u_int)(lim >> 30), pae_mode,
776 		    above4g_allow, above24g_allow);
777 	}
778 
779 	/*
780 	 * Find insertion point while checking for overlap.  Start off by
781 	 * assuming the new entry will be added to the end.
782 	 */
783 	insert_idx = physmap_idx + 2;
784 	for (i = 0; i <= physmap_idx; i += 2) {
785 		if (base < physmap[i + 1]) {
786 			if (base + length <= physmap[i]) {
787 				insert_idx = i;
788 				break;
789 			}
790 			if (boothowto & RB_VERBOSE)
791 				printf(
792 		    "Overlapping memory regions, ignoring second region\n");
793 			return (1);
794 		}
795 	}
796 
797 	/* See if we can prepend to the next entry. */
798 	if (insert_idx <= physmap_idx && base + length == physmap[insert_idx]) {
799 		physmap[insert_idx] = base;
800 		return (1);
801 	}
802 
803 	/* See if we can append to the previous entry. */
804 	if (insert_idx > 0 && base == physmap[insert_idx - 1]) {
805 		physmap[insert_idx - 1] += length;
806 		return (1);
807 	}
808 
809 	physmap_idx += 2;
810 	*physmap_idxp = physmap_idx;
811 	if (physmap_idx == PHYS_AVAIL_ENTRIES) {
812 		printf(
813 		"Too many segments in the physical address map, giving up\n");
814 		return (0);
815 	}
816 
817 	/*
818 	 * Move the last 'N' entries down to make room for the new
819 	 * entry if needed.
820 	 */
821 	for (i = physmap_idx; i > insert_idx; i -= 2) {
822 		physmap[i] = physmap[i - 2];
823 		physmap[i + 1] = physmap[i - 1];
824 	}
825 
826 	/* Insert the new entry. */
827 	physmap[insert_idx] = base;
828 	physmap[insert_idx + 1] = base + length;
829 	return (1);
830 }
831 
832 static int
833 add_smap_entry(struct bios_smap *smap, vm_paddr_t *physmap, int *physmap_idxp)
834 {
835 	if (boothowto & RB_VERBOSE)
836 		printf("SMAP type=%02x base=%016llx len=%016llx\n",
837 		    smap->type, smap->base, smap->length);
838 
839 	if (smap->type != SMAP_TYPE_MEMORY)
840 		return (1);
841 
842 	return (add_physmap_entry(smap->base, smap->length, physmap,
843 	    physmap_idxp));
844 }
845 
846 static void
847 add_smap_entries(struct bios_smap *smapbase, vm_paddr_t *physmap,
848     int *physmap_idxp)
849 {
850 	struct bios_smap *smap, *smapend;
851 	u_int32_t smapsize;
852 	/*
853 	 * Memory map from INT 15:E820.
854 	 *
855 	 * subr_module.c says:
856 	 * "Consumer may safely assume that size value precedes data."
857 	 * ie: an int32_t immediately precedes SMAP.
858 	 */
859 	smapsize = *((u_int32_t *)smapbase - 1);
860 	smapend = (struct bios_smap *)((uintptr_t)smapbase + smapsize);
861 
862 	for (smap = smapbase; smap < smapend; smap++)
863 		if (!add_smap_entry(smap, physmap, physmap_idxp))
864 			break;
865 }
866 
867 static void
868 basemem_setup(void)
869 {
870 
871 	if (basemem > 640) {
872 		printf("Preposterous BIOS basemem of %uK, truncating to 640K\n",
873 			basemem);
874 		basemem = 640;
875 	}
876 
877 	pmap_basemem_setup(basemem);
878 }
879 
880 /*
881  * Populate the (physmap) array with base/bound pairs describing the
882  * available physical memory in the system, then test this memory and
883  * build the phys_avail array describing the actually-available memory.
884  *
885  * If we cannot accurately determine the physical memory map, then use
886  * value from the 0xE801 call, and failing that, the RTC.
887  *
888  * Total memory size may be set by the kernel environment variable
889  * hw.physmem or the compile-time define MAXMEM.
890  *
891  * XXX first should be vm_paddr_t.
892  */
893 static void
894 getmemsize(int first)
895 {
896 	int has_smap, off, physmap_idx, pa_indx, da_indx;
897 	u_long memtest;
898 	vm_paddr_t physmap[PHYS_AVAIL_ENTRIES];
899 	quad_t dcons_addr, dcons_size, physmem_tunable;
900 	int hasbrokenint12, i, res __diagused;
901 	u_int extmem;
902 	struct vm86frame vmf;
903 	struct vm86context vmc;
904 	vm_paddr_t pa;
905 	struct bios_smap *smap, *smapbase;
906 	caddr_t kmdp;
907 
908 	has_smap = 0;
909 	bzero(&vmf, sizeof(vmf));
910 	bzero(physmap, sizeof(physmap));
911 	basemem = 0;
912 
913 	/*
914 	 * Tell the physical memory allocator about pages used to store
915 	 * the kernel and preloaded data.  See kmem_bootstrap_free().
916 	 */
917 	vm_phys_early_add_seg((vm_paddr_t)KERNLOAD, trunc_page(first));
918 
919 	TUNABLE_INT_FETCH("hw.above4g_allow", &above4g_allow);
920 	TUNABLE_INT_FETCH("hw.above24g_allow", &above24g_allow);
921 
922 	/*
923 	 * Check if the loader supplied an SMAP memory map.  If so,
924 	 * use that and do not make any VM86 calls.
925 	 */
926 	physmap_idx = 0;
927 	kmdp = preload_search_by_type("elf kernel");
928 	if (kmdp == NULL)
929 		kmdp = preload_search_by_type("elf32 kernel");
930 	smapbase = (struct bios_smap *)preload_search_info(kmdp,
931 	    MODINFO_METADATA | MODINFOMD_SMAP);
932 	if (smapbase != NULL) {
933 		add_smap_entries(smapbase, physmap, &physmap_idx);
934 		has_smap = 1;
935 		goto have_smap;
936 	}
937 
938 	/*
939 	 * Some newer BIOSes have a broken INT 12H implementation
940 	 * which causes a kernel panic immediately.  In this case, we
941 	 * need use the SMAP to determine the base memory size.
942 	 */
943 	hasbrokenint12 = 0;
944 	TUNABLE_INT_FETCH("hw.hasbrokenint12", &hasbrokenint12);
945 	if (hasbrokenint12 == 0) {
946 		/* Use INT12 to determine base memory size. */
947 		vm86_intcall(0x12, &vmf);
948 		basemem = vmf.vmf_ax;
949 		basemem_setup();
950 	}
951 
952 	/*
953 	 * Fetch the memory map with INT 15:E820.  Map page 1 R/W into
954 	 * the kernel page table so we can use it as a buffer.  The
955 	 * kernel will unmap this page later.
956 	 */
957 	vmc.npages = 0;
958 	smap = (void *)vm86_addpage(&vmc, 1, PMAP_MAP_LOW + ptoa(1));
959 	res = vm86_getptr(&vmc, (vm_offset_t)smap, &vmf.vmf_es, &vmf.vmf_di);
960 	KASSERT(res != 0, ("vm86_getptr() failed: address not found"));
961 
962 	vmf.vmf_ebx = 0;
963 	do {
964 		vmf.vmf_eax = 0xE820;
965 		vmf.vmf_edx = SMAP_SIG;
966 		vmf.vmf_ecx = sizeof(struct bios_smap);
967 		i = vm86_datacall(0x15, &vmf, &vmc);
968 		if (i || vmf.vmf_eax != SMAP_SIG)
969 			break;
970 		has_smap = 1;
971 		if (!add_smap_entry(smap, physmap, &physmap_idx))
972 			break;
973 	} while (vmf.vmf_ebx != 0);
974 
975 have_smap:
976 	/*
977 	 * If we didn't fetch the "base memory" size from INT12,
978 	 * figure it out from the SMAP (or just guess).
979 	 */
980 	if (basemem == 0) {
981 		for (i = 0; i <= physmap_idx; i += 2) {
982 			if (physmap[i] == 0x00000000) {
983 				basemem = physmap[i + 1] / 1024;
984 				break;
985 			}
986 		}
987 
988 		/* XXX: If we couldn't find basemem from SMAP, just guess. */
989 		if (basemem == 0)
990 			basemem = 640;
991 		basemem_setup();
992 	}
993 
994 	if (physmap[1] != 0)
995 		goto physmap_done;
996 
997 	/*
998 	 * If we failed to find an SMAP, figure out the extended
999 	 * memory size.  We will then build a simple memory map with
1000 	 * two segments, one for "base memory" and the second for
1001 	 * "extended memory".  Note that "extended memory" starts at a
1002 	 * physical address of 1MB and that both basemem and extmem
1003 	 * are in units of 1KB.
1004 	 *
1005 	 * First, try to fetch the extended memory size via INT 15:E801.
1006 	 */
1007 	vmf.vmf_ax = 0xE801;
1008 	if (vm86_intcall(0x15, &vmf) == 0) {
1009 		extmem = vmf.vmf_cx + vmf.vmf_dx * 64;
1010 	} else {
1011 		/*
1012 		 * If INT15:E801 fails, this is our last ditch effort
1013 		 * to determine the extended memory size.  Currently
1014 		 * we prefer the RTC value over INT15:88.
1015 		 */
1016 #if 0
1017 		vmf.vmf_ah = 0x88;
1018 		vm86_intcall(0x15, &vmf);
1019 		extmem = vmf.vmf_ax;
1020 #else
1021 		extmem = rtcin(RTC_EXTLO) + (rtcin(RTC_EXTHI) << 8);
1022 #endif
1023 	}
1024 
1025 	/*
1026 	 * Special hack for chipsets that still remap the 384k hole when
1027 	 * there's 16MB of memory - this really confuses people that
1028 	 * are trying to use bus mastering ISA controllers with the
1029 	 * "16MB limit"; they only have 16MB, but the remapping puts
1030 	 * them beyond the limit.
1031 	 *
1032 	 * If extended memory is between 15-16MB (16-17MB phys address range),
1033 	 *	chop it to 15MB.
1034 	 */
1035 	if ((extmem > 15 * 1024) && (extmem < 16 * 1024))
1036 		extmem = 15 * 1024;
1037 
1038 	physmap[0] = 0;
1039 	physmap[1] = basemem * 1024;
1040 	physmap_idx = 2;
1041 	physmap[physmap_idx] = 0x100000;
1042 	physmap[physmap_idx + 1] = physmap[physmap_idx] + extmem * 1024;
1043 
1044 physmap_done:
1045 	/*
1046 	 * Now, physmap contains a map of physical memory.
1047 	 */
1048 
1049 #ifdef SMP
1050 	/* make hole for AP bootstrap code */
1051 	alloc_ap_trampoline(physmap, &physmap_idx);
1052 #endif
1053 
1054 	/*
1055 	 * Maxmem isn't the "maximum memory", it's one larger than the
1056 	 * highest page of the physical address space.  It should be
1057 	 * called something like "Maxphyspage".  We may adjust this
1058 	 * based on ``hw.physmem'' and the results of the memory test.
1059 	 *
1060 	 * This is especially confusing when it is much larger than the
1061 	 * memory size and is displayed as "realmem".
1062 	 */
1063 	Maxmem = atop(physmap[physmap_idx + 1]);
1064 
1065 #ifdef MAXMEM
1066 	Maxmem = MAXMEM / 4;
1067 #endif
1068 
1069 	if (TUNABLE_QUAD_FETCH("hw.physmem", &physmem_tunable))
1070 		Maxmem = atop(physmem_tunable);
1071 
1072 	/*
1073 	 * If we have an SMAP, don't allow MAXMEM or hw.physmem to extend
1074 	 * the amount of memory in the system.
1075 	 */
1076 	if (has_smap && Maxmem > atop(physmap[physmap_idx + 1]))
1077 		Maxmem = atop(physmap[physmap_idx + 1]);
1078 
1079 	/*
1080 	 * The boot memory test is disabled by default, as it takes a
1081 	 * significant amount of time on large-memory systems, and is
1082 	 * unfriendly to virtual machines as it unnecessarily touches all
1083 	 * pages.
1084 	 *
1085 	 * A general name is used as the code may be extended to support
1086 	 * additional tests beyond the current "page present" test.
1087 	 */
1088 	memtest = 0;
1089 	TUNABLE_ULONG_FETCH("hw.memtest.tests", &memtest);
1090 
1091 	if (atop(physmap[physmap_idx + 1]) != Maxmem &&
1092 	    (boothowto & RB_VERBOSE))
1093 		printf("Physical memory use set to %ldK\n", Maxmem * 4);
1094 
1095 	/*
1096 	 * If Maxmem has been increased beyond what the system has detected,
1097 	 * extend the last memory segment to the new limit.
1098 	 */
1099 	if (atop(physmap[physmap_idx + 1]) < Maxmem)
1100 		physmap[physmap_idx + 1] = ptoa((vm_paddr_t)Maxmem);
1101 
1102 	/* call pmap initialization to make new kernel address space */
1103 	pmap_bootstrap(first);
1104 
1105 	/*
1106 	 * Size up each available chunk of physical memory.
1107 	 */
1108 	physmap[0] = PAGE_SIZE;		/* mask off page 0 */
1109 	pa_indx = 0;
1110 	da_indx = 1;
1111 	phys_avail[pa_indx++] = physmap[0];
1112 	phys_avail[pa_indx] = physmap[0];
1113 	dump_avail[da_indx] = physmap[0];
1114 
1115 	/*
1116 	 * Get dcons buffer address
1117 	 */
1118 	if (getenv_quad("dcons.addr", &dcons_addr) == 0 ||
1119 	    getenv_quad("dcons.size", &dcons_size) == 0)
1120 		dcons_addr = 0;
1121 
1122 	/*
1123 	 * physmap is in bytes, so when converting to page boundaries,
1124 	 * round up the start address and round down the end address.
1125 	 */
1126 	for (i = 0; i <= physmap_idx; i += 2) {
1127 		vm_paddr_t end;
1128 
1129 		end = ptoa((vm_paddr_t)Maxmem);
1130 		if (physmap[i + 1] < end)
1131 			end = trunc_page(physmap[i + 1]);
1132 		for (pa = round_page(physmap[i]); pa < end; pa += PAGE_SIZE) {
1133 			int *ptr;
1134 			int tmp;
1135 			bool full, page_bad;
1136 
1137 			full = false;
1138 			/*
1139 			 * block out kernel memory as not available.
1140 			 */
1141 			if (pa >= KERNLOAD && pa < first)
1142 				goto do_dump_avail;
1143 
1144 			/*
1145 			 * block out dcons buffer
1146 			 */
1147 			if (dcons_addr > 0
1148 			    && pa >= trunc_page(dcons_addr)
1149 			    && pa < dcons_addr + dcons_size)
1150 				goto do_dump_avail;
1151 
1152 			page_bad = false;
1153 			if (memtest == 0)
1154 				goto skip_memtest;
1155 
1156 			/*
1157 			 * map page into kernel: valid, read/write,non-cacheable
1158 			 */
1159 			ptr = (int *)pmap_cmap3(pa, PG_V | PG_RW | PG_N);
1160 
1161 			tmp = *(int *)ptr;
1162 			/*
1163 			 * Test for alternating 1's and 0's
1164 			 */
1165 			*(volatile int *)ptr = 0xaaaaaaaa;
1166 			if (*(volatile int *)ptr != 0xaaaaaaaa)
1167 				page_bad = true;
1168 			/*
1169 			 * Test for alternating 0's and 1's
1170 			 */
1171 			*(volatile int *)ptr = 0x55555555;
1172 			if (*(volatile int *)ptr != 0x55555555)
1173 				page_bad = true;
1174 			/*
1175 			 * Test for all 1's
1176 			 */
1177 			*(volatile int *)ptr = 0xffffffff;
1178 			if (*(volatile int *)ptr != 0xffffffff)
1179 				page_bad = true;
1180 			/*
1181 			 * Test for all 0's
1182 			 */
1183 			*(volatile int *)ptr = 0x0;
1184 			if (*(volatile int *)ptr != 0x0)
1185 				page_bad = true;
1186 			/*
1187 			 * Restore original value.
1188 			 */
1189 			*(int *)ptr = tmp;
1190 
1191 skip_memtest:
1192 			/*
1193 			 * Adjust array of valid/good pages.
1194 			 */
1195 			if (page_bad == true)
1196 				continue;
1197 			/*
1198 			 * If this good page is a continuation of the
1199 			 * previous set of good pages, then just increase
1200 			 * the end pointer. Otherwise start a new chunk.
1201 			 * Note that "end" points one higher than end,
1202 			 * making the range >= start and < end.
1203 			 * If we're also doing a speculative memory
1204 			 * test and we at or past the end, bump up Maxmem
1205 			 * so that we keep going. The first bad page
1206 			 * will terminate the loop.
1207 			 */
1208 			if (phys_avail[pa_indx] == pa) {
1209 				phys_avail[pa_indx] += PAGE_SIZE;
1210 			} else {
1211 				pa_indx++;
1212 				if (pa_indx == PHYS_AVAIL_ENTRIES) {
1213 					printf(
1214 		"Too many holes in the physical address space, giving up\n");
1215 					pa_indx--;
1216 					full = true;
1217 					goto do_dump_avail;
1218 				}
1219 				phys_avail[pa_indx++] = pa;	/* start */
1220 				phys_avail[pa_indx] = pa + PAGE_SIZE; /* end */
1221 			}
1222 			physmem++;
1223 do_dump_avail:
1224 			if (dump_avail[da_indx] == pa) {
1225 				dump_avail[da_indx] += PAGE_SIZE;
1226 			} else {
1227 				da_indx++;
1228 				if (da_indx == PHYS_AVAIL_ENTRIES) {
1229 					da_indx--;
1230 					goto do_next;
1231 				}
1232 				dump_avail[da_indx++] = pa;	/* start */
1233 				dump_avail[da_indx] = pa + PAGE_SIZE; /* end */
1234 			}
1235 do_next:
1236 			if (full)
1237 				break;
1238 		}
1239 	}
1240 	pmap_cmap3(0, 0);
1241 
1242 	/*
1243 	 * XXX
1244 	 * The last chunk must contain at least one page plus the message
1245 	 * buffer to avoid complicating other code (message buffer address
1246 	 * calculation, etc.).
1247 	 */
1248 	while (phys_avail[pa_indx - 1] + PAGE_SIZE +
1249 	    round_page(msgbufsize) >= phys_avail[pa_indx]) {
1250 		physmem -= atop(phys_avail[pa_indx] - phys_avail[pa_indx - 1]);
1251 		phys_avail[pa_indx--] = 0;
1252 		phys_avail[pa_indx--] = 0;
1253 	}
1254 
1255 	Maxmem = atop(phys_avail[pa_indx]);
1256 
1257 	/* Trim off space for the message buffer. */
1258 	phys_avail[pa_indx] -= round_page(msgbufsize);
1259 
1260 	/* Map the message buffer. */
1261 	for (off = 0; off < round_page(msgbufsize); off += PAGE_SIZE)
1262 		pmap_kenter((vm_offset_t)msgbufp + off, phys_avail[pa_indx] +
1263 		    off);
1264 }
1265 
1266 static void
1267 i386_kdb_init(void)
1268 {
1269 #ifdef DDB
1270 	db_fetch_ksymtab(bootinfo.bi_symtab, bootinfo.bi_esymtab, 0);
1271 #endif
1272 	kdb_init();
1273 #ifdef KDB
1274 	if (boothowto & RB_KDB)
1275 		kdb_enter(KDB_WHY_BOOTFLAGS, "Boot flags requested debugger");
1276 #endif
1277 }
1278 
1279 static void
1280 fixup_idt(void)
1281 {
1282 	struct gate_descriptor *ip;
1283 	uintptr_t off;
1284 	int x;
1285 
1286 	for (x = 0; x < NIDT; x++) {
1287 		ip = &idt[x];
1288 		if (ip->gd_type != SDT_SYS386IGT &&
1289 		    ip->gd_type != SDT_SYS386TGT)
1290 			continue;
1291 		off = ip->gd_looffset + (((u_int)ip->gd_hioffset) << 16);
1292 		KASSERT(off >= (uintptr_t)start_exceptions &&
1293 		    off < (uintptr_t)end_exceptions,
1294 		    ("IDT[%d] type %d off %#x", x, ip->gd_type, off));
1295 		off += setidt_disp;
1296 		MPASS(off >= PMAP_TRM_MIN_ADDRESS &&
1297 		    off < PMAP_TRM_MAX_ADDRESS);
1298 		ip->gd_looffset = off;
1299 		ip->gd_hioffset = off >> 16;
1300 	}
1301 }
1302 
1303 static void
1304 i386_setidt1(void)
1305 {
1306 	int x;
1307 
1308 	/* exceptions */
1309 	for (x = 0; x < NIDT; x++)
1310 		setidt(x, &IDTVEC(rsvd), SDT_SYS386IGT, SEL_KPL,
1311 		    GSEL(GCODE_SEL, SEL_KPL));
1312 	setidt(IDT_DE, &IDTVEC(div), SDT_SYS386IGT, SEL_KPL,
1313 	    GSEL(GCODE_SEL, SEL_KPL));
1314 	setidt(IDT_DB, &IDTVEC(dbg), SDT_SYS386IGT, SEL_KPL,
1315 	    GSEL(GCODE_SEL, SEL_KPL));
1316 	setidt(IDT_NMI, &IDTVEC(nmi), SDT_SYS386IGT, SEL_KPL,
1317 	    GSEL(GCODE_SEL, SEL_KPL));
1318 	setidt(IDT_BP, &IDTVEC(bpt), SDT_SYS386IGT, SEL_UPL,
1319 	    GSEL(GCODE_SEL, SEL_KPL));
1320 	setidt(IDT_OF, &IDTVEC(ofl), SDT_SYS386IGT, SEL_UPL,
1321 	    GSEL(GCODE_SEL, SEL_KPL));
1322 	setidt(IDT_BR, &IDTVEC(bnd), SDT_SYS386IGT, SEL_KPL,
1323 	    GSEL(GCODE_SEL, SEL_KPL));
1324 	setidt(IDT_UD, &IDTVEC(ill), SDT_SYS386IGT, SEL_KPL,
1325 	    GSEL(GCODE_SEL, SEL_KPL));
1326 	setidt(IDT_NM, &IDTVEC(dna), SDT_SYS386IGT, SEL_KPL,
1327 	    GSEL(GCODE_SEL, SEL_KPL));
1328 	setidt(IDT_DF, 0, SDT_SYSTASKGT, SEL_KPL, GSEL(GPANIC_SEL,
1329 	    SEL_KPL));
1330 	setidt(IDT_FPUGP, &IDTVEC(fpusegm), SDT_SYS386IGT,
1331 	    SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
1332 	setidt(IDT_TS, &IDTVEC(tss), SDT_SYS386IGT, SEL_KPL,
1333 	    GSEL(GCODE_SEL, SEL_KPL));
1334 	setidt(IDT_NP, &IDTVEC(missing), SDT_SYS386IGT, SEL_KPL,
1335 	    GSEL(GCODE_SEL, SEL_KPL));
1336 	setidt(IDT_SS, &IDTVEC(stk), SDT_SYS386IGT, SEL_KPL,
1337 	    GSEL(GCODE_SEL, SEL_KPL));
1338 	setidt(IDT_GP, &IDTVEC(prot), SDT_SYS386IGT, SEL_KPL,
1339 	    GSEL(GCODE_SEL, SEL_KPL));
1340 	setidt(IDT_PF, &IDTVEC(page), SDT_SYS386IGT, SEL_KPL,
1341 	    GSEL(GCODE_SEL, SEL_KPL));
1342 	setidt(IDT_MF, &IDTVEC(fpu), SDT_SYS386IGT, SEL_KPL,
1343 	    GSEL(GCODE_SEL, SEL_KPL));
1344 	setidt(IDT_AC, &IDTVEC(align), SDT_SYS386IGT, SEL_KPL,
1345 	    GSEL(GCODE_SEL, SEL_KPL));
1346 	setidt(IDT_MC, &IDTVEC(mchk), SDT_SYS386IGT, SEL_KPL,
1347 	    GSEL(GCODE_SEL, SEL_KPL));
1348 	setidt(IDT_XF, &IDTVEC(xmm), SDT_SYS386IGT, SEL_KPL,
1349 	    GSEL(GCODE_SEL, SEL_KPL));
1350 	setidt(IDT_SYSCALL, &IDTVEC(int0x80_syscall),
1351 	    SDT_SYS386IGT, SEL_UPL, GSEL(GCODE_SEL, SEL_KPL));
1352 #ifdef KDTRACE_HOOKS
1353 	setidt(IDT_DTRACE_RET, &IDTVEC(dtrace_ret),
1354 	    SDT_SYS386IGT, SEL_UPL, GSEL(GCODE_SEL, SEL_KPL));
1355 #endif
1356 #ifdef XENHVM
1357 	setidt(IDT_EVTCHN, &IDTVEC(xen_intr_upcall),
1358 	    SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
1359 #endif
1360 }
1361 
1362 static void
1363 i386_setidt2(void)
1364 {
1365 
1366 	setidt(IDT_UD, &IDTVEC(ill), SDT_SYS386IGT, SEL_KPL,
1367 	    GSEL(GCODE_SEL, SEL_KPL));
1368 	setidt(IDT_GP, &IDTVEC(prot), SDT_SYS386IGT, SEL_KPL,
1369 	    GSEL(GCODE_SEL, SEL_KPL));
1370 }
1371 
1372 #if defined(DEV_ISA) && !defined(DEV_ATPIC)
1373 static void
1374 i386_setidt3(void)
1375 {
1376 
1377 	setidt(IDT_IO_INTS + 7, IDTVEC(spuriousint),
1378 	    SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
1379 	setidt(IDT_IO_INTS + 15, IDTVEC(spuriousint),
1380 	    SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
1381 }
1382 #endif
1383 
1384 register_t
1385 init386(int first)
1386 {
1387 	struct region_descriptor r_gdt, r_idt;	/* table descriptors */
1388 	int gsel_tss, metadata_missing, x, pa;
1389 	struct pcpu *pc;
1390 	struct xstate_hdr *xhdr;
1391 	caddr_t kmdp;
1392 	vm_offset_t addend;
1393 	size_t ucode_len;
1394 
1395 	thread0.td_kstack = proc0kstack;
1396 	thread0.td_kstack_pages = TD0_KSTACK_PAGES;
1397 
1398 	/*
1399  	 * This may be done better later if it gets more high level
1400  	 * components in it. If so just link td->td_proc here.
1401 	 */
1402 	proc_linkup0(&proc0, &thread0);
1403 
1404 	if (bootinfo.bi_modulep) {
1405 		metadata_missing = 0;
1406 		addend = (vm_paddr_t)bootinfo.bi_modulep < KERNBASE ?
1407 		    PMAP_MAP_LOW : 0;
1408 		preload_metadata = (caddr_t)bootinfo.bi_modulep + addend;
1409 		preload_bootstrap_relocate(addend);
1410 	} else {
1411 		metadata_missing = 1;
1412 	}
1413 
1414 	if (bootinfo.bi_envp != 0) {
1415 		addend = (vm_paddr_t)bootinfo.bi_envp < KERNBASE ?
1416 		    PMAP_MAP_LOW : 0;
1417 		init_static_kenv((char *)bootinfo.bi_envp + addend, 0);
1418 	} else {
1419 		init_static_kenv(NULL, 0);
1420 	}
1421 
1422 	/*
1423 	 * Re-evaluate CPU features if we loaded a microcode update.
1424 	 */
1425 	ucode_len = ucode_load_bsp(first);
1426 	if (ucode_len != 0) {
1427 		identify_cpu();
1428 		first = roundup2(first + ucode_len, PAGE_SIZE);
1429 	}
1430 
1431 	identify_hypervisor();
1432 	identify_hypervisor_smbios();
1433 
1434 	/* Init basic tunables, hz etc */
1435 	init_param1();
1436 
1437 	/* Set bootmethod to BIOS: it's the only supported on i386. */
1438 	strlcpy(bootmethod, "BIOS", sizeof(bootmethod));
1439 
1440 	/*
1441 	 * Make gdt memory segments.  All segments cover the full 4GB
1442 	 * of address space and permissions are enforced at page level.
1443 	 */
1444 	gdt_segs[GCODE_SEL].ssd_limit = atop(0 - 1);
1445 	gdt_segs[GDATA_SEL].ssd_limit = atop(0 - 1);
1446 	gdt_segs[GUCODE_SEL].ssd_limit = atop(0 - 1);
1447 	gdt_segs[GUDATA_SEL].ssd_limit = atop(0 - 1);
1448 	gdt_segs[GUFS_SEL].ssd_limit = atop(0 - 1);
1449 	gdt_segs[GUGS_SEL].ssd_limit = atop(0 - 1);
1450 
1451 	pc = &__pcpu[0];
1452 	gdt_segs[GPRIV_SEL].ssd_limit = atop(0 - 1);
1453 	gdt_segs[GPRIV_SEL].ssd_base = (int)pc;
1454 	gdt_segs[GPROC0_SEL].ssd_base = (int)&common_tss0;
1455 
1456 	for (x = 0; x < NGDT; x++)
1457 		ssdtosd(&gdt_segs[x], &gdt0[x].sd);
1458 
1459 	r_gdt.rd_limit = NGDT * sizeof(gdt0[0]) - 1;
1460 	r_gdt.rd_base =  (int)gdt0;
1461 	mtx_init(&dt_lock, "descriptor tables", NULL, MTX_SPIN);
1462 	lgdt(&r_gdt);
1463 
1464 	pcpu_init(pc, 0, sizeof(struct pcpu));
1465 	for (pa = first; pa < first + DPCPU_SIZE; pa += PAGE_SIZE)
1466 		pmap_kenter(pa, pa);
1467 	dpcpu_init((void *)first, 0);
1468 	first += DPCPU_SIZE;
1469 	PCPU_SET(prvspace, pc);
1470 	PCPU_SET(curthread, &thread0);
1471 	/* Non-late cninit() and printf() can be moved up to here. */
1472 
1473 	/*
1474 	 * Initialize mutexes.
1475 	 *
1476 	 * icu_lock: in order to allow an interrupt to occur in a critical
1477 	 * 	     section, to set pcpu->ipending (etc...) properly, we
1478 	 *	     must be able to get the icu lock, so it can't be
1479 	 *	     under witness.
1480 	 */
1481 	mutex_init();
1482 	mtx_init(&icu_lock, "icu", NULL, MTX_SPIN | MTX_NOWITNESS | MTX_NOPROFILE);
1483 
1484 	i386_setidt1();
1485 
1486 	r_idt.rd_limit = sizeof(idt0) - 1;
1487 	r_idt.rd_base = (int) idt;
1488 	lidt(&r_idt);
1489 
1490 	finishidentcpu();	/* Final stage of CPU initialization */
1491 
1492 	/*
1493 	 * Initialize the clock before the console so that console
1494 	 * initialization can use DELAY().
1495 	 */
1496 	clock_init();
1497 
1498 	i386_setidt2();
1499 	pmap_set_nx();
1500 	initializecpu();	/* Initialize CPU registers */
1501 	initializecpucache();
1502 
1503 	/* pointer to selector slot for %fs/%gs */
1504 	PCPU_SET(fsgs_gdt, &gdt[GUFS_SEL].sd);
1505 
1506 	/* Initialize the tss (except for the final esp0) early for vm86. */
1507 	common_tss0.tss_esp0 = thread0.td_kstack + thread0.td_kstack_pages *
1508 	    PAGE_SIZE - VM86_STACK_SPACE;
1509 	common_tss0.tss_ss0 = GSEL(GDATA_SEL, SEL_KPL);
1510 	common_tss0.tss_ioopt = sizeof(struct i386tss) << 16;
1511 	gsel_tss = GSEL(GPROC0_SEL, SEL_KPL);
1512 	PCPU_SET(tss_gdt, &gdt[GPROC0_SEL].sd);
1513 	PCPU_SET(common_tssd, *PCPU_GET(tss_gdt));
1514 	ltr(gsel_tss);
1515 
1516 	/* Initialize the PIC early for vm86 calls. */
1517 #ifdef DEV_ISA
1518 #ifdef DEV_ATPIC
1519 	elcr_probe();
1520 	atpic_startup();
1521 #else
1522 	/* Reset and mask the atpics and leave them shut down. */
1523 	atpic_reset();
1524 
1525 	/*
1526 	 * Point the ICU spurious interrupt vectors at the APIC spurious
1527 	 * interrupt handler.
1528 	 */
1529 	i386_setidt3();
1530 #endif
1531 #endif
1532 
1533 	/*
1534 	 * The console and kdb should be initialized even earlier than here,
1535 	 * but some console drivers don't work until after getmemsize().
1536 	 * Default to late console initialization to support these drivers.
1537 	 * This loses mainly printf()s in getmemsize() and early debugging.
1538 	 */
1539 	TUNABLE_INT_FETCH("debug.late_console", &late_console);
1540 	if (!late_console) {
1541 		cninit();
1542 		i386_kdb_init();
1543 	}
1544 
1545 	if (cpu_fxsr && (cpu_feature2 & CPUID2_XSAVE) != 0) {
1546 		use_xsave = 1;
1547 		TUNABLE_INT_FETCH("hw.use_xsave", &use_xsave);
1548 	}
1549 
1550 	kmdp = preload_search_by_type("elf kernel");
1551 	link_elf_ireloc(kmdp);
1552 
1553 	vm86_initialize();
1554 	getmemsize(first);
1555 	init_param2(physmem);
1556 
1557 	/* now running on new page tables, configured,and u/iom is accessible */
1558 
1559 	if (late_console)
1560 		cninit();
1561 
1562 	if (metadata_missing)
1563 		printf("WARNING: loader(8) metadata is missing!\n");
1564 
1565 	if (late_console)
1566 		i386_kdb_init();
1567 
1568 	msgbufinit(msgbufp, msgbufsize);
1569 	npxinit(true);
1570 
1571 	/*
1572 	 * Set up thread0 pcb after npxinit calculated pcb + fpu save
1573 	 * area size.  Zero out the extended state header in fpu save
1574 	 * area.
1575 	 */
1576 	thread0.td_pcb = get_pcb_td(&thread0);
1577 	thread0.td_pcb->pcb_save = get_pcb_user_save_td(&thread0);
1578 	bzero(get_pcb_user_save_td(&thread0), cpu_max_ext_state_size);
1579 	if (use_xsave) {
1580 		xhdr = (struct xstate_hdr *)(get_pcb_user_save_td(&thread0) +
1581 		    1);
1582 		xhdr->xstate_bv = xsave_mask;
1583 	}
1584 	PCPU_SET(curpcb, thread0.td_pcb);
1585 	/* Move esp0 in the tss to its final place. */
1586 	/* Note: -16 is so we can grow the trapframe if we came from vm86 */
1587 	common_tss0.tss_esp0 = (vm_offset_t)thread0.td_pcb - VM86_STACK_SPACE;
1588 	PCPU_SET(kesp0, common_tss0.tss_esp0);
1589 	gdt[GPROC0_SEL].sd.sd_type = SDT_SYS386TSS;	/* clear busy bit */
1590 	ltr(gsel_tss);
1591 
1592 	/* transfer to user mode */
1593 
1594 	_ucodesel = GSEL(GUCODE_SEL, SEL_UPL);
1595 	_udatasel = GSEL(GUDATA_SEL, SEL_UPL);
1596 
1597 	/* setup proc 0's pcb */
1598 	thread0.td_pcb->pcb_flags = 0;
1599 	thread0.td_pcb->pcb_cr3 = pmap_get_kcr3();
1600 	thread0.td_pcb->pcb_ext = 0;
1601 	thread0.td_frame = &proc0_tf;
1602 
1603 #ifdef FDT
1604 	x86_init_fdt();
1605 #endif
1606 
1607 	/* Location of kernel stack for locore */
1608 	return ((register_t)thread0.td_pcb);
1609 }
1610 
1611 static void
1612 machdep_init_trampoline(void)
1613 {
1614 	struct region_descriptor r_gdt, r_idt;
1615 	struct i386tss *tss;
1616 	char *copyout_buf, *trampoline, *tramp_stack_base;
1617 	int x;
1618 
1619 	gdt = pmap_trm_alloc(sizeof(union descriptor) * NGDT * mp_ncpus,
1620 	    M_NOWAIT | M_ZERO);
1621 	bcopy(gdt0, gdt, sizeof(union descriptor) * NGDT);
1622 	r_gdt.rd_limit = NGDT * sizeof(gdt[0]) - 1;
1623 	r_gdt.rd_base = (int)gdt;
1624 	lgdt(&r_gdt);
1625 
1626 	tss = pmap_trm_alloc(sizeof(struct i386tss) * mp_ncpus,
1627 	    M_NOWAIT | M_ZERO);
1628 	bcopy(&common_tss0, tss, sizeof(struct i386tss));
1629 	gdt[GPROC0_SEL].sd.sd_lobase = (int)tss;
1630 	gdt[GPROC0_SEL].sd.sd_hibase = (u_int)tss >> 24;
1631 	gdt[GPROC0_SEL].sd.sd_type = SDT_SYS386TSS;
1632 
1633 	PCPU_SET(fsgs_gdt, &gdt[GUFS_SEL].sd);
1634 	PCPU_SET(tss_gdt, &gdt[GPROC0_SEL].sd);
1635 	PCPU_SET(common_tssd, *PCPU_GET(tss_gdt));
1636 	PCPU_SET(common_tssp, tss);
1637 	ltr(GSEL(GPROC0_SEL, SEL_KPL));
1638 
1639 	trampoline = pmap_trm_alloc(end_exceptions - start_exceptions,
1640 	    M_NOWAIT);
1641 	bcopy(start_exceptions, trampoline, end_exceptions - start_exceptions);
1642 	tramp_stack_base = pmap_trm_alloc(TRAMP_STACK_SZ, M_NOWAIT);
1643 	PCPU_SET(trampstk, (uintptr_t)tramp_stack_base + TRAMP_STACK_SZ -
1644 	    VM86_STACK_SPACE);
1645 	tss[0].tss_esp0 = PCPU_GET(trampstk);
1646 
1647 	idt = pmap_trm_alloc(sizeof(idt0), M_NOWAIT | M_ZERO);
1648 	bcopy(idt0, idt, sizeof(idt0));
1649 
1650 	/* Re-initialize new IDT since the handlers were relocated */
1651 	setidt_disp = trampoline - start_exceptions;
1652 	if (bootverbose)
1653 		printf("Trampoline disposition %#zx\n", setidt_disp);
1654 	fixup_idt();
1655 
1656 	r_idt.rd_limit = sizeof(struct gate_descriptor) * NIDT - 1;
1657 	r_idt.rd_base = (int)idt;
1658 	lidt(&r_idt);
1659 
1660 	/* dblfault TSS */
1661 	dblfault_tss = pmap_trm_alloc(sizeof(struct i386tss), M_NOWAIT | M_ZERO);
1662 	dblfault_stack = pmap_trm_alloc(PAGE_SIZE, M_NOWAIT);
1663 	dblfault_tss->tss_esp = dblfault_tss->tss_esp0 =
1664 	    dblfault_tss->tss_esp1 = dblfault_tss->tss_esp2 =
1665 	    (int)dblfault_stack + PAGE_SIZE;
1666 	dblfault_tss->tss_ss = dblfault_tss->tss_ss0 = dblfault_tss->tss_ss1 =
1667 	    dblfault_tss->tss_ss2 = GSEL(GDATA_SEL, SEL_KPL);
1668 	dblfault_tss->tss_cr3 = pmap_get_kcr3();
1669 	dblfault_tss->tss_eip = (int)dblfault_handler;
1670 	dblfault_tss->tss_eflags = PSL_KERNEL;
1671 	dblfault_tss->tss_ds = dblfault_tss->tss_es =
1672 	    dblfault_tss->tss_gs = GSEL(GDATA_SEL, SEL_KPL);
1673 	dblfault_tss->tss_fs = GSEL(GPRIV_SEL, SEL_KPL);
1674 	dblfault_tss->tss_cs = GSEL(GCODE_SEL, SEL_KPL);
1675 	dblfault_tss->tss_ldt = GSEL(GLDT_SEL, SEL_KPL);
1676 	gdt[GPANIC_SEL].sd.sd_lobase = (int)dblfault_tss;
1677 	gdt[GPANIC_SEL].sd.sd_hibase = (u_int)dblfault_tss >> 24;
1678 
1679 	/* make ldt memory segments */
1680 	ldt = pmap_trm_alloc(sizeof(union descriptor) * NLDT,
1681 	    M_NOWAIT | M_ZERO);
1682 	gdt[GLDT_SEL].sd.sd_lobase = (int)ldt;
1683 	gdt[GLDT_SEL].sd.sd_hibase = (u_int)ldt >> 24;
1684 	ldt_segs[LUCODE_SEL].ssd_limit = atop(0 - 1);
1685 	ldt_segs[LUDATA_SEL].ssd_limit = atop(0 - 1);
1686 	for (x = 0; x < nitems(ldt_segs); x++)
1687 		ssdtosd(&ldt_segs[x], &ldt[x].sd);
1688 
1689 	_default_ldt = GSEL(GLDT_SEL, SEL_KPL);
1690 	lldt(_default_ldt);
1691 	PCPU_SET(currentldt, _default_ldt);
1692 
1693 	copyout_buf = pmap_trm_alloc(TRAMP_COPYOUT_SZ, M_NOWAIT);
1694 	PCPU_SET(copyout_buf, copyout_buf);
1695 	copyout_init_tramp();
1696 }
1697 SYSINIT(vm_mem, SI_SUB_VM, SI_ORDER_SECOND, machdep_init_trampoline, NULL);
1698 
1699 #ifdef COMPAT_43
1700 static void
1701 i386_setup_lcall_gate(void)
1702 {
1703 	struct sysentvec *sv;
1704 	struct user_segment_descriptor desc;
1705 	u_int lcall_addr;
1706 
1707 	sv = &elf32_freebsd_sysvec;
1708 	lcall_addr = (uintptr_t)sv->sv_psstrings - sz_lcall_tramp;
1709 
1710 	bzero(&desc, sizeof(desc));
1711 	desc.sd_type = SDT_MEMERA;
1712 	desc.sd_dpl = SEL_UPL;
1713 	desc.sd_p = 1;
1714 	desc.sd_def32 = 1;
1715 	desc.sd_gran = 1;
1716 	desc.sd_lolimit = 0xffff;
1717 	desc.sd_hilimit = 0xf;
1718 	desc.sd_lobase = lcall_addr;
1719 	desc.sd_hibase = lcall_addr >> 24;
1720 	bcopy(&desc, &ldt[LSYS5CALLS_SEL], sizeof(desc));
1721 }
1722 SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_ANY, i386_setup_lcall_gate, NULL);
1723 #endif
1724 
1725 void
1726 cpu_pcpu_init(struct pcpu *pcpu, int cpuid, size_t size)
1727 {
1728 
1729 	pcpu->pc_acpi_id = 0xffffffff;
1730 }
1731 
1732 static int
1733 smap_sysctl_handler(SYSCTL_HANDLER_ARGS)
1734 {
1735 	struct bios_smap *smapbase;
1736 	struct bios_smap_xattr smap;
1737 	caddr_t kmdp;
1738 	uint32_t *smapattr;
1739 	int count, error, i;
1740 
1741 	/* Retrieve the system memory map from the loader. */
1742 	kmdp = preload_search_by_type("elf kernel");
1743 	if (kmdp == NULL)
1744 		kmdp = preload_search_by_type("elf32 kernel");
1745 	smapbase = (struct bios_smap *)preload_search_info(kmdp,
1746 	    MODINFO_METADATA | MODINFOMD_SMAP);
1747 	if (smapbase == NULL)
1748 		return (0);
1749 	smapattr = (uint32_t *)preload_search_info(kmdp,
1750 	    MODINFO_METADATA | MODINFOMD_SMAP_XATTR);
1751 	count = *((u_int32_t *)smapbase - 1) / sizeof(*smapbase);
1752 	error = 0;
1753 	for (i = 0; i < count; i++) {
1754 		smap.base = smapbase[i].base;
1755 		smap.length = smapbase[i].length;
1756 		smap.type = smapbase[i].type;
1757 		if (smapattr != NULL)
1758 			smap.xattr = smapattr[i];
1759 		else
1760 			smap.xattr = 0;
1761 		error = SYSCTL_OUT(req, &smap, sizeof(smap));
1762 	}
1763 	return (error);
1764 }
1765 SYSCTL_PROC(_machdep, OID_AUTO, smap,
1766     CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
1767     smap_sysctl_handler, "S,bios_smap_xattr",
1768     "Raw BIOS SMAP data");
1769 
1770 void
1771 spinlock_enter(void)
1772 {
1773 	struct thread *td;
1774 	register_t flags;
1775 
1776 	td = curthread;
1777 	if (td->td_md.md_spinlock_count == 0) {
1778 		flags = intr_disable();
1779 		td->td_md.md_spinlock_count = 1;
1780 		td->td_md.md_saved_flags = flags;
1781 		critical_enter();
1782 	} else
1783 		td->td_md.md_spinlock_count++;
1784 }
1785 
1786 void
1787 spinlock_exit(void)
1788 {
1789 	struct thread *td;
1790 	register_t flags;
1791 
1792 	td = curthread;
1793 	flags = td->td_md.md_saved_flags;
1794 	td->td_md.md_spinlock_count--;
1795 	if (td->td_md.md_spinlock_count == 0) {
1796 		critical_exit();
1797 		intr_restore(flags);
1798 	}
1799 }
1800 
1801 #if defined(I586_CPU) && !defined(NO_F00F_HACK)
1802 static void f00f_hack(void *unused);
1803 SYSINIT(f00f_hack, SI_SUB_INTRINSIC, SI_ORDER_FIRST, f00f_hack, NULL);
1804 
1805 static void
1806 f00f_hack(void *unused)
1807 {
1808 	struct region_descriptor r_idt;
1809 	struct gate_descriptor *new_idt;
1810 	vm_offset_t tmp;
1811 
1812 	if (!has_f00f_bug)
1813 		return;
1814 
1815 	printf("Intel Pentium detected, installing workaround for F00F bug\n");
1816 
1817 	tmp = (vm_offset_t)pmap_trm_alloc(PAGE_SIZE * 3, M_NOWAIT | M_ZERO);
1818 	if (tmp == 0)
1819 		panic("kmem_malloc returned 0");
1820 	tmp = round_page(tmp);
1821 
1822 	/* Put the problematic entry (#6) at the end of the lower page. */
1823 	new_idt = (struct gate_descriptor *)
1824 	    (tmp + PAGE_SIZE - 7 * sizeof(struct gate_descriptor));
1825 	bcopy(idt, new_idt, sizeof(idt0));
1826 	r_idt.rd_base = (u_int)new_idt;
1827 	r_idt.rd_limit = sizeof(idt0) - 1;
1828 	lidt(&r_idt);
1829 	/* SMP machines do not need the F00F hack. */
1830 	idt = new_idt;
1831 	pmap_protect(kernel_pmap, tmp, tmp + PAGE_SIZE, VM_PROT_READ);
1832 }
1833 #endif /* defined(I586_CPU) && !NO_F00F_HACK */
1834 
1835 /*
1836  * Construct a PCB from a trapframe. This is called from kdb_trap() where
1837  * we want to start a backtrace from the function that caused us to enter
1838  * the debugger. We have the context in the trapframe, but base the trace
1839  * on the PCB. The PCB doesn't have to be perfect, as long as it contains
1840  * enough for a backtrace.
1841  */
1842 void
1843 makectx(struct trapframe *tf, struct pcb *pcb)
1844 {
1845 
1846 	pcb->pcb_edi = tf->tf_edi;
1847 	pcb->pcb_esi = tf->tf_esi;
1848 	pcb->pcb_ebp = tf->tf_ebp;
1849 	pcb->pcb_ebx = tf->tf_ebx;
1850 	pcb->pcb_eip = tf->tf_eip;
1851 	pcb->pcb_esp = (ISPL(tf->tf_cs)) ? tf->tf_esp : (int)(tf + 1) - 8;
1852 	pcb->pcb_gs = rgs();
1853 }
1854 
1855 #ifdef KDB
1856 
1857 /*
1858  * Provide inb() and outb() as functions.  They are normally only available as
1859  * inline functions, thus cannot be called from the debugger.
1860  */
1861 
1862 /* silence compiler warnings */
1863 u_char inb_(u_short);
1864 void outb_(u_short, u_char);
1865 
1866 u_char
1867 inb_(u_short port)
1868 {
1869 	return inb(port);
1870 }
1871 
1872 void
1873 outb_(u_short port, u_char data)
1874 {
1875 	outb(port, data);
1876 }
1877 
1878 #endif /* KDB */
1879