vmmapi.c revision 249905
1/*-
2 * Copyright (c) 2011 NetApp, Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: head/lib/libvmmapi/vmmapi.c 249905 2013-04-25 20:42:21Z neel $
27 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD: head/lib/libvmmapi/vmmapi.c 249905 2013-04-25 20:42:21Z neel $");
31
32#include <sys/types.h>
33#include <sys/sysctl.h>
34#include <sys/ioctl.h>
35#include <sys/mman.h>
36
37#include <machine/specialreg.h>
38
39#include <stdio.h>
40#include <stdlib.h>
41#include <assert.h>
42#include <string.h>
43#include <fcntl.h>
44#include <unistd.h>
45
46#include <machine/vmm.h>
47#include <machine/vmm_dev.h>
48
49#include "vmmapi.h"
50
51#define	GB	(1024 * 1024 * 1024UL)
52
53struct vmctx {
54	int	fd;
55	uint32_t lowmem_limit;
56	enum vm_mmap_style vms;
57	size_t	lowmem;
58	char	*lowmem_addr;
59	size_t	highmem;
60	char	*highmem_addr;
61	char	*name;
62};
63
64#define	CREATE(x)  sysctlbyname("hw.vmm.create", NULL, NULL, (x), strlen((x)))
65#define	DESTROY(x) sysctlbyname("hw.vmm.destroy", NULL, NULL, (x), strlen((x)))
66
67static int
68vm_device_open(const char *name)
69{
70        int fd, len;
71        char *vmfile;
72
73	len = strlen("/dev/vmm/") + strlen(name) + 1;
74	vmfile = malloc(len);
75	assert(vmfile != NULL);
76	snprintf(vmfile, len, "/dev/vmm/%s", name);
77
78        /* Open the device file */
79        fd = open(vmfile, O_RDWR, 0);
80
81	free(vmfile);
82        return (fd);
83}
84
85int
86vm_create(const char *name)
87{
88
89	return (CREATE((char *)name));
90}
91
92struct vmctx *
93vm_open(const char *name)
94{
95	struct vmctx *vm;
96
97	vm = malloc(sizeof(struct vmctx) + strlen(name) + 1);
98	assert(vm != NULL);
99
100	vm->fd = -1;
101	vm->lowmem_limit = 3 * GB;
102	vm->name = (char *)(vm + 1);
103	strcpy(vm->name, name);
104
105	if ((vm->fd = vm_device_open(vm->name)) < 0)
106		goto err;
107
108	return (vm);
109err:
110	vm_destroy(vm);
111	return (NULL);
112}
113
114void
115vm_destroy(struct vmctx *vm)
116{
117	assert(vm != NULL);
118
119	if (vm->fd >= 0)
120		close(vm->fd);
121	DESTROY(vm->name);
122
123	free(vm);
124}
125
126int
127vm_get_memory_seg(struct vmctx *ctx, vm_paddr_t gpa, size_t *ret_len)
128{
129	int error;
130	struct vm_memory_segment seg;
131
132	bzero(&seg, sizeof(seg));
133	seg.gpa = gpa;
134	error = ioctl(ctx->fd, VM_GET_MEMORY_SEG, &seg);
135	*ret_len = seg.len;
136	return (error);
137}
138
139uint32_t
140vm_get_lowmem_limit(struct vmctx *ctx)
141{
142
143	return (ctx->lowmem_limit);
144}
145
146void
147vm_set_lowmem_limit(struct vmctx *ctx, uint32_t limit)
148{
149
150	ctx->lowmem_limit = limit;
151}
152
153static int
154setup_memory_segment(struct vmctx *ctx, vm_paddr_t gpa, size_t len, char **addr)
155{
156	int error;
157	struct vm_memory_segment seg;
158
159	/*
160	 * Create and optionally map 'len' bytes of memory at guest
161	 * physical address 'gpa'
162	 */
163	bzero(&seg, sizeof(seg));
164	seg.gpa = gpa;
165	seg.len = len;
166	error = ioctl(ctx->fd, VM_MAP_MEMORY, &seg);
167	if (error == 0 && addr != NULL) {
168		*addr = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_SHARED,
169				ctx->fd, gpa);
170	}
171	return (error);
172}
173
174int
175vm_setup_memory(struct vmctx *ctx, size_t memsize, enum vm_mmap_style vms)
176{
177	char **addr;
178	int error;
179
180	/* XXX VM_MMAP_SPARSE not implemented yet */
181	assert(vms == VM_MMAP_NONE || vms == VM_MMAP_ALL);
182	ctx->vms = vms;
183
184	/*
185	 * If 'memsize' cannot fit entirely in the 'lowmem' segment then
186	 * create another 'highmem' segment above 4GB for the remainder.
187	 */
188	if (memsize > ctx->lowmem_limit) {
189		ctx->lowmem = ctx->lowmem_limit;
190		ctx->highmem = memsize - ctx->lowmem;
191	} else {
192		ctx->lowmem = memsize;
193		ctx->highmem = 0;
194	}
195
196	if (ctx->lowmem > 0) {
197		addr = (vms == VM_MMAP_ALL) ? &ctx->lowmem_addr : NULL;
198		error = setup_memory_segment(ctx, 0, ctx->lowmem, addr);
199		if (error)
200			return (error);
201	}
202
203	if (ctx->highmem > 0) {
204		addr = (vms == VM_MMAP_ALL) ? &ctx->highmem_addr : NULL;
205		error = setup_memory_segment(ctx, 4*GB, ctx->highmem, addr);
206		if (error)
207			return (error);
208	}
209
210	return (0);
211}
212
213void *
214vm_map_gpa(struct vmctx *ctx, vm_paddr_t gaddr, size_t len)
215{
216
217	/* XXX VM_MMAP_SPARSE not implemented yet */
218	assert(ctx->vms == VM_MMAP_ALL);
219
220	if (gaddr < ctx->lowmem && gaddr + len <= ctx->lowmem)
221		return ((void *)(ctx->lowmem_addr + gaddr));
222
223	if (gaddr >= 4*GB) {
224		gaddr -= 4*GB;
225		if (gaddr < ctx->highmem && gaddr + len <= ctx->highmem)
226			return ((void *)(ctx->highmem_addr + gaddr));
227	}
228
229	return (NULL);
230}
231
232int
233vm_set_desc(struct vmctx *ctx, int vcpu, int reg,
234	    uint64_t base, uint32_t limit, uint32_t access)
235{
236	int error;
237	struct vm_seg_desc vmsegdesc;
238
239	bzero(&vmsegdesc, sizeof(vmsegdesc));
240	vmsegdesc.cpuid = vcpu;
241	vmsegdesc.regnum = reg;
242	vmsegdesc.desc.base = base;
243	vmsegdesc.desc.limit = limit;
244	vmsegdesc.desc.access = access;
245
246	error = ioctl(ctx->fd, VM_SET_SEGMENT_DESCRIPTOR, &vmsegdesc);
247	return (error);
248}
249
250int
251vm_get_desc(struct vmctx *ctx, int vcpu, int reg,
252	    uint64_t *base, uint32_t *limit, uint32_t *access)
253{
254	int error;
255	struct vm_seg_desc vmsegdesc;
256
257	bzero(&vmsegdesc, sizeof(vmsegdesc));
258	vmsegdesc.cpuid = vcpu;
259	vmsegdesc.regnum = reg;
260
261	error = ioctl(ctx->fd, VM_GET_SEGMENT_DESCRIPTOR, &vmsegdesc);
262	if (error == 0) {
263		*base = vmsegdesc.desc.base;
264		*limit = vmsegdesc.desc.limit;
265		*access = vmsegdesc.desc.access;
266	}
267	return (error);
268}
269
270int
271vm_set_register(struct vmctx *ctx, int vcpu, int reg, uint64_t val)
272{
273	int error;
274	struct vm_register vmreg;
275
276	bzero(&vmreg, sizeof(vmreg));
277	vmreg.cpuid = vcpu;
278	vmreg.regnum = reg;
279	vmreg.regval = val;
280
281	error = ioctl(ctx->fd, VM_SET_REGISTER, &vmreg);
282	return (error);
283}
284
285int
286vm_get_register(struct vmctx *ctx, int vcpu, int reg, uint64_t *ret_val)
287{
288	int error;
289	struct vm_register vmreg;
290
291	bzero(&vmreg, sizeof(vmreg));
292	vmreg.cpuid = vcpu;
293	vmreg.regnum = reg;
294
295	error = ioctl(ctx->fd, VM_GET_REGISTER, &vmreg);
296	*ret_val = vmreg.regval;
297	return (error);
298}
299
300int
301vm_run(struct vmctx *ctx, int vcpu, uint64_t rip, struct vm_exit *vmexit)
302{
303	int error;
304	struct vm_run vmrun;
305
306	bzero(&vmrun, sizeof(vmrun));
307	vmrun.cpuid = vcpu;
308	vmrun.rip = rip;
309
310	error = ioctl(ctx->fd, VM_RUN, &vmrun);
311	bcopy(&vmrun.vm_exit, vmexit, sizeof(struct vm_exit));
312	return (error);
313}
314
315static int
316vm_inject_event_real(struct vmctx *ctx, int vcpu, enum vm_event_type type,
317		     int vector, int error_code, int error_code_valid)
318{
319	struct vm_event ev;
320
321	bzero(&ev, sizeof(ev));
322	ev.cpuid = vcpu;
323	ev.type = type;
324	ev.vector = vector;
325	ev.error_code = error_code;
326	ev.error_code_valid = error_code_valid;
327
328	return (ioctl(ctx->fd, VM_INJECT_EVENT, &ev));
329}
330
331int
332vm_inject_event(struct vmctx *ctx, int vcpu, enum vm_event_type type,
333		int vector)
334{
335
336	return (vm_inject_event_real(ctx, vcpu, type, vector, 0, 0));
337}
338
339int
340vm_inject_event2(struct vmctx *ctx, int vcpu, enum vm_event_type type,
341		 int vector, int error_code)
342{
343
344	return (vm_inject_event_real(ctx, vcpu, type, vector, error_code, 1));
345}
346
347int
348vm_apicid2vcpu(struct vmctx *ctx, int apicid)
349{
350	/*
351	 * The apic id associated with the 'vcpu' has the same numerical value
352	 * as the 'vcpu' itself.
353	 */
354	return (apicid);
355}
356
357int
358vm_lapic_irq(struct vmctx *ctx, int vcpu, int vector)
359{
360	struct vm_lapic_irq vmirq;
361
362	bzero(&vmirq, sizeof(vmirq));
363	vmirq.cpuid = vcpu;
364	vmirq.vector = vector;
365
366	return (ioctl(ctx->fd, VM_LAPIC_IRQ, &vmirq));
367}
368
369int
370vm_inject_nmi(struct vmctx *ctx, int vcpu)
371{
372	struct vm_nmi vmnmi;
373
374	bzero(&vmnmi, sizeof(vmnmi));
375	vmnmi.cpuid = vcpu;
376
377	return (ioctl(ctx->fd, VM_INJECT_NMI, &vmnmi));
378}
379
380static struct {
381	const char	*name;
382	int		type;
383} capstrmap[] = {
384	{ "hlt_exit",		VM_CAP_HALT_EXIT },
385	{ "mtrap_exit",		VM_CAP_MTRAP_EXIT },
386	{ "pause_exit",		VM_CAP_PAUSE_EXIT },
387	{ "unrestricted_guest",	VM_CAP_UNRESTRICTED_GUEST },
388	{ 0 }
389};
390
391int
392vm_capability_name2type(const char *capname)
393{
394	int i;
395
396	for (i = 0; capstrmap[i].name != NULL && capname != NULL; i++) {
397		if (strcmp(capstrmap[i].name, capname) == 0)
398			return (capstrmap[i].type);
399	}
400
401	return (-1);
402}
403
404const char *
405vm_capability_type2name(int type)
406{
407	int i;
408
409	for (i = 0; capstrmap[i].name != NULL; i++) {
410		if (capstrmap[i].type == type)
411			return (capstrmap[i].name);
412	}
413
414	return (NULL);
415}
416
417int
418vm_get_capability(struct vmctx *ctx, int vcpu, enum vm_cap_type cap,
419		  int *retval)
420{
421	int error;
422	struct vm_capability vmcap;
423
424	bzero(&vmcap, sizeof(vmcap));
425	vmcap.cpuid = vcpu;
426	vmcap.captype = cap;
427
428	error = ioctl(ctx->fd, VM_GET_CAPABILITY, &vmcap);
429	*retval = vmcap.capval;
430	return (error);
431}
432
433int
434vm_set_capability(struct vmctx *ctx, int vcpu, enum vm_cap_type cap, int val)
435{
436	struct vm_capability vmcap;
437
438	bzero(&vmcap, sizeof(vmcap));
439	vmcap.cpuid = vcpu;
440	vmcap.captype = cap;
441	vmcap.capval = val;
442
443	return (ioctl(ctx->fd, VM_SET_CAPABILITY, &vmcap));
444}
445
446int
447vm_assign_pptdev(struct vmctx *ctx, int bus, int slot, int func)
448{
449	struct vm_pptdev pptdev;
450
451	bzero(&pptdev, sizeof(pptdev));
452	pptdev.bus = bus;
453	pptdev.slot = slot;
454	pptdev.func = func;
455
456	return (ioctl(ctx->fd, VM_BIND_PPTDEV, &pptdev));
457}
458
459int
460vm_unassign_pptdev(struct vmctx *ctx, int bus, int slot, int func)
461{
462	struct vm_pptdev pptdev;
463
464	bzero(&pptdev, sizeof(pptdev));
465	pptdev.bus = bus;
466	pptdev.slot = slot;
467	pptdev.func = func;
468
469	return (ioctl(ctx->fd, VM_UNBIND_PPTDEV, &pptdev));
470}
471
472int
473vm_map_pptdev_mmio(struct vmctx *ctx, int bus, int slot, int func,
474		   vm_paddr_t gpa, size_t len, vm_paddr_t hpa)
475{
476	struct vm_pptdev_mmio pptmmio;
477
478	bzero(&pptmmio, sizeof(pptmmio));
479	pptmmio.bus = bus;
480	pptmmio.slot = slot;
481	pptmmio.func = func;
482	pptmmio.gpa = gpa;
483	pptmmio.len = len;
484	pptmmio.hpa = hpa;
485
486	return (ioctl(ctx->fd, VM_MAP_PPTDEV_MMIO, &pptmmio));
487}
488
489int
490vm_setup_msi(struct vmctx *ctx, int vcpu, int bus, int slot, int func,
491	     int destcpu, int vector, int numvec)
492{
493	struct vm_pptdev_msi pptmsi;
494
495	bzero(&pptmsi, sizeof(pptmsi));
496	pptmsi.vcpu = vcpu;
497	pptmsi.bus = bus;
498	pptmsi.slot = slot;
499	pptmsi.func = func;
500	pptmsi.destcpu = destcpu;
501	pptmsi.vector = vector;
502	pptmsi.numvec = numvec;
503
504	return (ioctl(ctx->fd, VM_PPTDEV_MSI, &pptmsi));
505}
506
507int
508vm_setup_msix(struct vmctx *ctx, int vcpu, int bus, int slot, int func,
509	      int idx, uint32_t msg, uint32_t vector_control, uint64_t addr)
510{
511	struct vm_pptdev_msix pptmsix;
512
513	bzero(&pptmsix, sizeof(pptmsix));
514	pptmsix.vcpu = vcpu;
515	pptmsix.bus = bus;
516	pptmsix.slot = slot;
517	pptmsix.func = func;
518	pptmsix.idx = idx;
519	pptmsix.msg = msg;
520	pptmsix.addr = addr;
521	pptmsix.vector_control = vector_control;
522
523	return ioctl(ctx->fd, VM_PPTDEV_MSIX, &pptmsix);
524}
525
526uint64_t *
527vm_get_stats(struct vmctx *ctx, int vcpu, struct timeval *ret_tv,
528	     int *ret_entries)
529{
530	int error;
531
532	static struct vm_stats vmstats;
533
534	vmstats.cpuid = vcpu;
535
536	error = ioctl(ctx->fd, VM_STATS, &vmstats);
537	if (error == 0) {
538		if (ret_entries)
539			*ret_entries = vmstats.num_entries;
540		if (ret_tv)
541			*ret_tv = vmstats.tv;
542		return (vmstats.statbuf);
543	} else
544		return (NULL);
545}
546
547const char *
548vm_get_stat_desc(struct vmctx *ctx, int index)
549{
550	static struct vm_stat_desc statdesc;
551
552	statdesc.index = index;
553	if (ioctl(ctx->fd, VM_STAT_DESC, &statdesc) == 0)
554		return (statdesc.desc);
555	else
556		return (NULL);
557}
558
559int
560vm_get_x2apic_state(struct vmctx *ctx, int vcpu, enum x2apic_state *state)
561{
562	int error;
563	struct vm_x2apic x2apic;
564
565	bzero(&x2apic, sizeof(x2apic));
566	x2apic.cpuid = vcpu;
567
568	error = ioctl(ctx->fd, VM_GET_X2APIC_STATE, &x2apic);
569	*state = x2apic.state;
570	return (error);
571}
572
573int
574vm_set_x2apic_state(struct vmctx *ctx, int vcpu, enum x2apic_state state)
575{
576	int error;
577	struct vm_x2apic x2apic;
578
579	bzero(&x2apic, sizeof(x2apic));
580	x2apic.cpuid = vcpu;
581	x2apic.state = state;
582
583	error = ioctl(ctx->fd, VM_SET_X2APIC_STATE, &x2apic);
584
585	return (error);
586}
587
588/*
589 * From Intel Vol 3a:
590 * Table 9-1. IA-32 Processor States Following Power-up, Reset or INIT
591 */
592int
593vcpu_reset(struct vmctx *vmctx, int vcpu)
594{
595	int error;
596	uint64_t rflags, rip, cr0, cr4, zero, desc_base, rdx;
597	uint32_t desc_access, desc_limit;
598	uint16_t sel;
599
600	zero = 0;
601
602	rflags = 0x2;
603	error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RFLAGS, rflags);
604	if (error)
605		goto done;
606
607	rip = 0xfff0;
608	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RIP, rip)) != 0)
609		goto done;
610
611	cr0 = CR0_NE;
612	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_CR0, cr0)) != 0)
613		goto done;
614
615	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_CR3, zero)) != 0)
616		goto done;
617
618	cr4 = 0;
619	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_CR4, cr4)) != 0)
620		goto done;
621
622	/*
623	 * CS: present, r/w, accessed, 16-bit, byte granularity, usable
624	 */
625	desc_base = 0xffff0000;
626	desc_limit = 0xffff;
627	desc_access = 0x0093;
628	error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_CS,
629			    desc_base, desc_limit, desc_access);
630	if (error)
631		goto done;
632
633	sel = 0xf000;
634	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_CS, sel)) != 0)
635		goto done;
636
637	/*
638	 * SS,DS,ES,FS,GS: present, r/w, accessed, 16-bit, byte granularity
639	 */
640	desc_base = 0;
641	desc_limit = 0xffff;
642	desc_access = 0x0093;
643	error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_SS,
644			    desc_base, desc_limit, desc_access);
645	if (error)
646		goto done;
647
648	error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_DS,
649			    desc_base, desc_limit, desc_access);
650	if (error)
651		goto done;
652
653	error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_ES,
654			    desc_base, desc_limit, desc_access);
655	if (error)
656		goto done;
657
658	error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_FS,
659			    desc_base, desc_limit, desc_access);
660	if (error)
661		goto done;
662
663	error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_GS,
664			    desc_base, desc_limit, desc_access);
665	if (error)
666		goto done;
667
668	sel = 0;
669	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_SS, sel)) != 0)
670		goto done;
671	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_DS, sel)) != 0)
672		goto done;
673	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_ES, sel)) != 0)
674		goto done;
675	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_FS, sel)) != 0)
676		goto done;
677	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_GS, sel)) != 0)
678		goto done;
679
680	/* General purpose registers */
681	rdx = 0xf00;
682	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RAX, zero)) != 0)
683		goto done;
684	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RBX, zero)) != 0)
685		goto done;
686	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RCX, zero)) != 0)
687		goto done;
688	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RDX, rdx)) != 0)
689		goto done;
690	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RSI, zero)) != 0)
691		goto done;
692	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RDI, zero)) != 0)
693		goto done;
694	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RBP, zero)) != 0)
695		goto done;
696	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RSP, zero)) != 0)
697		goto done;
698
699	/* GDTR, IDTR */
700	desc_base = 0;
701	desc_limit = 0xffff;
702	desc_access = 0;
703	error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_GDTR,
704			    desc_base, desc_limit, desc_access);
705	if (error != 0)
706		goto done;
707
708	error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_IDTR,
709			    desc_base, desc_limit, desc_access);
710	if (error != 0)
711		goto done;
712
713	/* TR */
714	desc_base = 0;
715	desc_limit = 0xffff;
716	desc_access = 0x0000008b;
717	error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_TR, 0, 0, desc_access);
718	if (error)
719		goto done;
720
721	sel = 0;
722	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_TR, sel)) != 0)
723		goto done;
724
725	/* LDTR */
726	desc_base = 0;
727	desc_limit = 0xffff;
728	desc_access = 0x00000082;
729	error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_LDTR, desc_base,
730			    desc_limit, desc_access);
731	if (error)
732		goto done;
733
734	sel = 0;
735	if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_LDTR, 0)) != 0)
736		goto done;
737
738	/* XXX cr2, debug registers */
739
740	error = 0;
741done:
742	return (error);
743}
744