xref: /freebsd/sys/amd64/vmm/intel/vmcs.c (revision cc16dea626cf2fc80cde667ac4798065108e596c)
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  * $FreeBSD$
27  */
28 
29 #include "opt_ddb.h"
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/pcpu.h>
37 
38 #include <vm/vm.h>
39 #include <vm/pmap.h>
40 
41 #include <machine/segments.h>
42 #include <machine/pmap.h>
43 
44 #include <machine/vmm.h>
45 #include "vmm_host.h"
46 #include "vmcs.h"
47 #include "vmx_cpufunc.h"
48 #include "ept.h"
49 #include "vmx.h"
50 
51 #ifdef DDB
52 #include <ddb/ddb.h>
53 #endif
54 
55 static uint64_t
56 vmcs_fix_regval(uint32_t encoding, uint64_t val)
57 {
58 
59 	switch (encoding) {
60 	case VMCS_GUEST_CR0:
61 		val = vmx_fix_cr0(val);
62 		break;
63 	case VMCS_GUEST_CR4:
64 		val = vmx_fix_cr4(val);
65 		break;
66 	default:
67 		break;
68 	}
69 	return (val);
70 }
71 
72 static uint32_t
73 vmcs_field_encoding(int ident)
74 {
75 	switch (ident) {
76 	case VM_REG_GUEST_CR0:
77 		return (VMCS_GUEST_CR0);
78 	case VM_REG_GUEST_CR3:
79 		return (VMCS_GUEST_CR3);
80 	case VM_REG_GUEST_CR4:
81 		return (VMCS_GUEST_CR4);
82 	case VM_REG_GUEST_DR7:
83 		return (VMCS_GUEST_DR7);
84 	case VM_REG_GUEST_RSP:
85 		return (VMCS_GUEST_RSP);
86 	case VM_REG_GUEST_RIP:
87 		return (VMCS_GUEST_RIP);
88 	case VM_REG_GUEST_RFLAGS:
89 		return (VMCS_GUEST_RFLAGS);
90 	case VM_REG_GUEST_ES:
91 		return (VMCS_GUEST_ES_SELECTOR);
92 	case VM_REG_GUEST_CS:
93 		return (VMCS_GUEST_CS_SELECTOR);
94 	case VM_REG_GUEST_SS:
95 		return (VMCS_GUEST_SS_SELECTOR);
96 	case VM_REG_GUEST_DS:
97 		return (VMCS_GUEST_DS_SELECTOR);
98 	case VM_REG_GUEST_FS:
99 		return (VMCS_GUEST_FS_SELECTOR);
100 	case VM_REG_GUEST_GS:
101 		return (VMCS_GUEST_GS_SELECTOR);
102 	case VM_REG_GUEST_TR:
103 		return (VMCS_GUEST_TR_SELECTOR);
104 	case VM_REG_GUEST_LDTR:
105 		return (VMCS_GUEST_LDTR_SELECTOR);
106 	case VM_REG_GUEST_EFER:
107 		return (VMCS_GUEST_IA32_EFER);
108 	default:
109 		return (-1);
110 	}
111 
112 }
113 
114 static int
115 vmcs_seg_desc_encoding(int seg, uint32_t *base, uint32_t *lim, uint32_t *acc)
116 {
117 
118 	switch (seg) {
119 	case VM_REG_GUEST_ES:
120 		*base = VMCS_GUEST_ES_BASE;
121 		*lim = VMCS_GUEST_ES_LIMIT;
122 		*acc = VMCS_GUEST_ES_ACCESS_RIGHTS;
123 		break;
124 	case VM_REG_GUEST_CS:
125 		*base = VMCS_GUEST_CS_BASE;
126 		*lim = VMCS_GUEST_CS_LIMIT;
127 		*acc = VMCS_GUEST_CS_ACCESS_RIGHTS;
128 		break;
129 	case VM_REG_GUEST_SS:
130 		*base = VMCS_GUEST_SS_BASE;
131 		*lim = VMCS_GUEST_SS_LIMIT;
132 		*acc = VMCS_GUEST_SS_ACCESS_RIGHTS;
133 		break;
134 	case VM_REG_GUEST_DS:
135 		*base = VMCS_GUEST_DS_BASE;
136 		*lim = VMCS_GUEST_DS_LIMIT;
137 		*acc = VMCS_GUEST_DS_ACCESS_RIGHTS;
138 		break;
139 	case VM_REG_GUEST_FS:
140 		*base = VMCS_GUEST_FS_BASE;
141 		*lim = VMCS_GUEST_FS_LIMIT;
142 		*acc = VMCS_GUEST_FS_ACCESS_RIGHTS;
143 		break;
144 	case VM_REG_GUEST_GS:
145 		*base = VMCS_GUEST_GS_BASE;
146 		*lim = VMCS_GUEST_GS_LIMIT;
147 		*acc = VMCS_GUEST_GS_ACCESS_RIGHTS;
148 		break;
149 	case VM_REG_GUEST_TR:
150 		*base = VMCS_GUEST_TR_BASE;
151 		*lim = VMCS_GUEST_TR_LIMIT;
152 		*acc = VMCS_GUEST_TR_ACCESS_RIGHTS;
153 		break;
154 	case VM_REG_GUEST_LDTR:
155 		*base = VMCS_GUEST_LDTR_BASE;
156 		*lim = VMCS_GUEST_LDTR_LIMIT;
157 		*acc = VMCS_GUEST_LDTR_ACCESS_RIGHTS;
158 		break;
159 	case VM_REG_GUEST_IDTR:
160 		*base = VMCS_GUEST_IDTR_BASE;
161 		*lim = VMCS_GUEST_IDTR_LIMIT;
162 		*acc = VMCS_INVALID_ENCODING;
163 		break;
164 	case VM_REG_GUEST_GDTR:
165 		*base = VMCS_GUEST_GDTR_BASE;
166 		*lim = VMCS_GUEST_GDTR_LIMIT;
167 		*acc = VMCS_INVALID_ENCODING;
168 		break;
169 	default:
170 		return (EINVAL);
171 	}
172 
173 	return (0);
174 }
175 
176 int
177 vmcs_getreg(struct vmcs *vmcs, int running, int ident, uint64_t *retval)
178 {
179 	int error;
180 	uint32_t encoding;
181 
182 	/*
183 	 * If we need to get at vmx-specific state in the VMCS we can bypass
184 	 * the translation of 'ident' to 'encoding' by simply setting the
185 	 * sign bit. As it so happens the upper 16 bits are reserved (i.e
186 	 * set to 0) in the encodings for the VMCS so we are free to use the
187 	 * sign bit.
188 	 */
189 	if (ident < 0)
190 		encoding = ident & 0x7fffffff;
191 	else
192 		encoding = vmcs_field_encoding(ident);
193 
194 	if (encoding == (uint32_t)-1)
195 		return (EINVAL);
196 
197 	if (!running)
198 		VMPTRLD(vmcs);
199 
200 	error = vmread(encoding, retval);
201 
202 	if (!running)
203 		VMCLEAR(vmcs);
204 
205 	return (error);
206 }
207 
208 int
209 vmcs_setreg(struct vmcs *vmcs, int running, int ident, uint64_t val)
210 {
211 	int error;
212 	uint32_t encoding;
213 
214 	if (ident < 0)
215 		encoding = ident & 0x7fffffff;
216 	else
217 		encoding = vmcs_field_encoding(ident);
218 
219 	if (encoding == (uint32_t)-1)
220 		return (EINVAL);
221 
222 	val = vmcs_fix_regval(encoding, val);
223 
224 	if (!running)
225 		VMPTRLD(vmcs);
226 
227 	error = vmwrite(encoding, val);
228 
229 	if (!running)
230 		VMCLEAR(vmcs);
231 
232 	return (error);
233 }
234 
235 int
236 vmcs_setdesc(struct vmcs *vmcs, int seg, struct seg_desc *desc)
237 {
238 	int error;
239 	uint32_t base, limit, access;
240 
241 	error = vmcs_seg_desc_encoding(seg, &base, &limit, &access);
242 	if (error != 0)
243 		panic("vmcs_setdesc: invalid segment register %d", seg);
244 
245 	VMPTRLD(vmcs);
246 	if ((error = vmwrite(base, desc->base)) != 0)
247 		goto done;
248 
249 	if ((error = vmwrite(limit, desc->limit)) != 0)
250 		goto done;
251 
252 	if (access != VMCS_INVALID_ENCODING) {
253 		if ((error = vmwrite(access, desc->access)) != 0)
254 			goto done;
255 	}
256 done:
257 	VMCLEAR(vmcs);
258 	return (error);
259 }
260 
261 int
262 vmcs_getdesc(struct vmcs *vmcs, int seg, struct seg_desc *desc)
263 {
264 	int error;
265 	uint32_t base, limit, access;
266 	uint64_t u64;
267 
268 	error = vmcs_seg_desc_encoding(seg, &base, &limit, &access);
269 	if (error != 0)
270 		panic("vmcs_getdesc: invalid segment register %d", seg);
271 
272 	VMPTRLD(vmcs);
273 	if ((error = vmread(base, &u64)) != 0)
274 		goto done;
275 	desc->base = u64;
276 
277 	if ((error = vmread(limit, &u64)) != 0)
278 		goto done;
279 	desc->limit = u64;
280 
281 	if (access != VMCS_INVALID_ENCODING) {
282 		if ((error = vmread(access, &u64)) != 0)
283 			goto done;
284 		desc->access = u64;
285 	}
286 done:
287 	VMCLEAR(vmcs);
288 	return (error);
289 }
290 
291 int
292 vmcs_set_msr_save(struct vmcs *vmcs, u_long g_area, u_int g_count)
293 {
294 	int error;
295 
296 	VMPTRLD(vmcs);
297 
298 	/*
299 	 * Guest MSRs are saved in the VM-exit MSR-store area.
300 	 * Guest MSRs are loaded from the VM-entry MSR-load area.
301 	 * Both areas point to the same location in memory.
302 	 */
303 	if ((error = vmwrite(VMCS_EXIT_MSR_STORE, g_area)) != 0)
304 		goto done;
305 	if ((error = vmwrite(VMCS_EXIT_MSR_STORE_COUNT, g_count)) != 0)
306 		goto done;
307 
308 	if ((error = vmwrite(VMCS_ENTRY_MSR_LOAD, g_area)) != 0)
309 		goto done;
310 	if ((error = vmwrite(VMCS_ENTRY_MSR_LOAD_COUNT, g_count)) != 0)
311 		goto done;
312 
313 	error = 0;
314 done:
315 	VMCLEAR(vmcs);
316 	return (error);
317 }
318 
319 int
320 vmcs_set_defaults(struct vmcs *vmcs,
321 		  u_long host_rip, u_long host_rsp, u_long ept_pml4,
322 		  uint32_t pinbased_ctls, uint32_t procbased_ctls,
323 		  uint32_t procbased_ctls2, uint32_t exit_ctls,
324 		  uint32_t entry_ctls, u_long msr_bitmap, uint16_t vpid)
325 {
326 	int error, codesel, datasel, tsssel;
327 	u_long cr0, cr4, efer;
328 	uint64_t eptp, pat, fsbase, idtrbase;
329 	uint32_t exc_bitmap;
330 
331 	codesel = vmm_get_host_codesel();
332 	datasel = vmm_get_host_datasel();
333 	tsssel = vmm_get_host_tsssel();
334 
335 	/*
336 	 * Make sure we have a "current" VMCS to work with.
337 	 */
338 	VMPTRLD(vmcs);
339 
340 	/*
341 	 * Load the VMX controls
342 	 */
343 	if ((error = vmwrite(VMCS_PIN_BASED_CTLS, pinbased_ctls)) != 0)
344 		goto done;
345 	if ((error = vmwrite(VMCS_PRI_PROC_BASED_CTLS, procbased_ctls)) != 0)
346 		goto done;
347 	if ((error = vmwrite(VMCS_SEC_PROC_BASED_CTLS, procbased_ctls2)) != 0)
348 		goto done;
349 	if ((error = vmwrite(VMCS_EXIT_CTLS, exit_ctls)) != 0)
350 		goto done;
351 	if ((error = vmwrite(VMCS_ENTRY_CTLS, entry_ctls)) != 0)
352 		goto done;
353 
354 	/* Guest state */
355 
356 	/* Initialize guest IA32_PAT MSR with the default value */
357 	pat = PAT_VALUE(0, PAT_WRITE_BACK)	|
358 	      PAT_VALUE(1, PAT_WRITE_THROUGH)	|
359 	      PAT_VALUE(2, PAT_UNCACHED)	|
360 	      PAT_VALUE(3, PAT_UNCACHEABLE)	|
361 	      PAT_VALUE(4, PAT_WRITE_BACK)	|
362 	      PAT_VALUE(5, PAT_WRITE_THROUGH)	|
363 	      PAT_VALUE(6, PAT_UNCACHED)	|
364 	      PAT_VALUE(7, PAT_UNCACHEABLE);
365 	if ((error = vmwrite(VMCS_GUEST_IA32_PAT, pat)) != 0)
366 		goto done;
367 
368 	/* Host state */
369 
370 	/* Initialize host IA32_PAT MSR */
371 	pat = vmm_get_host_pat();
372 	if ((error = vmwrite(VMCS_HOST_IA32_PAT, pat)) != 0)
373 		goto done;
374 
375 	/* Load the IA32_EFER MSR */
376 	efer = vmm_get_host_efer();
377 	if ((error = vmwrite(VMCS_HOST_IA32_EFER, efer)) != 0)
378 		goto done;
379 
380 	/* Load the control registers */
381 
382 	cr0 = vmm_get_host_cr0();
383 	if ((error = vmwrite(VMCS_HOST_CR0, cr0)) != 0)
384 		goto done;
385 
386 	cr4 = vmm_get_host_cr4() | CR4_VMXE;
387 	if ((error = vmwrite(VMCS_HOST_CR4, cr4)) != 0)
388 		goto done;
389 
390 	/* Load the segment selectors */
391 	if ((error = vmwrite(VMCS_HOST_ES_SELECTOR, datasel)) != 0)
392 		goto done;
393 
394 	if ((error = vmwrite(VMCS_HOST_CS_SELECTOR, codesel)) != 0)
395 		goto done;
396 
397 	if ((error = vmwrite(VMCS_HOST_SS_SELECTOR, datasel)) != 0)
398 		goto done;
399 
400 	if ((error = vmwrite(VMCS_HOST_DS_SELECTOR, datasel)) != 0)
401 		goto done;
402 
403 	if ((error = vmwrite(VMCS_HOST_FS_SELECTOR, datasel)) != 0)
404 		goto done;
405 
406 	if ((error = vmwrite(VMCS_HOST_GS_SELECTOR, datasel)) != 0)
407 		goto done;
408 
409 	if ((error = vmwrite(VMCS_HOST_TR_SELECTOR, tsssel)) != 0)
410 		goto done;
411 
412 	/*
413 	 * Load the Base-Address for %fs and idtr.
414 	 *
415 	 * Note that we exclude %gs, tss and gdtr here because their base
416 	 * address is pcpu specific.
417 	 */
418 	fsbase = vmm_get_host_fsbase();
419 	if ((error = vmwrite(VMCS_HOST_FS_BASE, fsbase)) != 0)
420 		goto done;
421 
422 	idtrbase = vmm_get_host_idtrbase();
423 	if ((error = vmwrite(VMCS_HOST_IDTR_BASE, idtrbase)) != 0)
424 		goto done;
425 
426 	/* instruction pointer */
427 	if ((error = vmwrite(VMCS_HOST_RIP, host_rip)) != 0)
428 		goto done;
429 
430 	/* stack pointer */
431 	if ((error = vmwrite(VMCS_HOST_RSP, host_rsp)) != 0)
432 		goto done;
433 
434 	/* eptp */
435 	eptp = EPTP(ept_pml4);
436 	if ((error = vmwrite(VMCS_EPTP, eptp)) != 0)
437 		goto done;
438 
439 	/* vpid */
440 	if ((error = vmwrite(VMCS_VPID, vpid)) != 0)
441 		goto done;
442 
443 	/* msr bitmap */
444 	if ((error = vmwrite(VMCS_MSR_BITMAP, msr_bitmap)) != 0)
445 		goto done;
446 
447 	/* exception bitmap */
448 	exc_bitmap = 1 << IDT_MC;
449 	if ((error = vmwrite(VMCS_EXCEPTION_BITMAP, exc_bitmap)) != 0)
450 		goto done;
451 
452 	/* link pointer */
453 	if ((error = vmwrite(VMCS_LINK_POINTER, ~0)) != 0)
454 		goto done;
455 done:
456 	VMCLEAR(vmcs);
457 	return (error);
458 }
459 
460 uint64_t
461 vmcs_read(uint32_t encoding)
462 {
463 	int error;
464 	uint64_t val;
465 
466 	error = vmread(encoding, &val);
467 	if (error != 0)
468 		panic("vmcs_read(%u) error %d", encoding, error);
469 
470 	return (val);
471 }
472 
473 #ifdef DDB
474 extern int vmxon_enabled[];
475 
476 DB_SHOW_COMMAND(vmcs, db_show_vmcs)
477 {
478 	uint64_t cur_vmcs, val;
479 	uint32_t exit;
480 
481 	if (!vmxon_enabled[curcpu]) {
482 		db_printf("VMX not enabled\n");
483 		return;
484 	}
485 
486 	if (have_addr) {
487 		db_printf("Only current VMCS supported\n");
488 		return;
489 	}
490 
491 	vmptrst(&cur_vmcs);
492 	if (cur_vmcs == VMCS_INITIAL) {
493 		db_printf("No current VM context\n");
494 		return;
495 	}
496 	db_printf("VMCS: %jx\n", cur_vmcs);
497 	db_printf("VPID: %lu\n", vmcs_read(VMCS_VPID));
498 	db_printf("Activity: ");
499 	val = vmcs_read(VMCS_GUEST_ACTIVITY);
500 	switch (val) {
501 	case 0:
502 		db_printf("Active");
503 		break;
504 	case 1:
505 		db_printf("HLT");
506 		break;
507 	case 2:
508 		db_printf("Shutdown");
509 		break;
510 	case 3:
511 		db_printf("Wait for SIPI");
512 		break;
513 	default:
514 		db_printf("Unknown: %#lx", val);
515 	}
516 	db_printf("\n");
517 	exit = vmcs_read(VMCS_EXIT_REASON);
518 	if (exit & 0x80000000)
519 		db_printf("Entry Failure Reason: %u\n", exit & 0xffff);
520 	else
521 		db_printf("Exit Reason: %u\n", exit & 0xffff);
522 	db_printf("Qualification: %#lx\n", vmcs_exit_qualification());
523 	db_printf("Guest Linear Address: %#lx\n",
524 	    vmcs_read(VMCS_GUEST_LINEAR_ADDRESS));
525 	switch (exit & 0x8000ffff) {
526 	case EXIT_REASON_EXCEPTION:
527 	case EXIT_REASON_EXT_INTR:
528 		val = vmcs_read(VMCS_EXIT_INTERRUPTION_INFO);
529 		db_printf("Interrupt Type: ");
530 		switch (val >> 8 & 0x7) {
531 		case 0:
532 			db_printf("external");
533 			break;
534 		case 2:
535 			db_printf("NMI");
536 			break;
537 		case 3:
538 			db_printf("HW exception");
539 			break;
540 		case 4:
541 			db_printf("SW exception");
542 			break;
543 		default:
544 			db_printf("?? %lu", val >> 8 & 0x7);
545 			break;
546 		}
547 		db_printf("  Vector: %lu", val & 0xff);
548 		if (val & 0x800)
549 			db_printf("  Error Code: %lx",
550 			    vmcs_read(VMCS_EXIT_INTERRUPTION_ERROR));
551 		db_printf("\n");
552 		break;
553 	case EXIT_REASON_EPT_FAULT:
554 	case EXIT_REASON_EPT_MISCONFIG:
555 		db_printf("Guest Physical Address: %#lx\n",
556 		    vmcs_read(VMCS_GUEST_PHYSICAL_ADDRESS));
557 		break;
558 	}
559 	db_printf("VM-instruction error: %#lx\n", vmcs_instruction_error());
560 }
561 #endif
562