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kvm: x86: Add kvm_x86_ops hook that enables XSAVES for guest
[mirror_ubuntu-bionic-kernel.git] / arch / x86 / kvm / cpuid.c
CommitLineData
00b27a3e
AK		 1/*
2 * Kernel-based Virtual Machine driver for Linux
3 * cpuid support routines
4 *
5 * derived from arch/x86/kvm/x86.c
6 *
7 * Copyright 2011 Red Hat, Inc. and/or its affiliates.
8 * Copyright IBM Corporation, 2008
9 *
10 * This work is licensed under the terms of the GNU GPL, version 2. See
11 * the COPYING file in the top-level directory.
12 *
13 */
14
15#include <linux/kvm_host.h>
16#include <linux/module.h>
bb5a798a
JK		 17#include <linux/vmalloc.h>
18#include <linux/uaccess.h>
00b27a3e
AK		 19#include <asm/user.h>
20#include <asm/xsave.h>
21#include "cpuid.h"
22#include "lapic.h"
23#include "mmu.h"
24#include "trace.h"
25
4344ee98
PB		 26static u32 xstate_required_size(u64 xstate_bv)
27{
28 int feature_bit = 0;
29 u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
30
56c103ec 31 xstate_bv &= XSTATE_EXTEND_MASK;
4344ee98
PB		 32 while (xstate_bv) {
33 if (xstate_bv & 0x1) {
34 u32 eax, ebx, ecx, edx;
35 cpuid_count(0xD, feature_bit, &eax, &ebx, &ecx, &edx);
36 ret = max(ret, eax + ebx);
37 }
38
39 xstate_bv >>= 1;
40 feature_bit++;
41 }
42
43 return ret;
44}
45
4ff41732
PB		 46u64 kvm_supported_xcr0(void)
47{
48 u64 xcr0 = KVM_SUPPORTED_XCR0 & host_xcr0;
49
93c4adc7 50 if (!kvm_x86_ops->mpx_supported())
4ff41732
PB		 51 xcr0 &= ~(XSTATE_BNDREGS | XSTATE_BNDCSR);
52
53 return xcr0;
54}
55
5c404cab
PB		 56#define F(x) bit(X86_FEATURE_##x)
57
dd598091 58int kvm_update_cpuid(struct kvm_vcpu *vcpu)
00b27a3e
AK		 59{
60 struct kvm_cpuid_entry2 *best;
61 struct kvm_lapic *apic = vcpu->arch.apic;
62
63 best = kvm_find_cpuid_entry(vcpu, 1, 0);
64 if (!best)
dd598091 65 return 0;
00b27a3e
AK		 66
67 /* Update OSXSAVE bit */
68 if (cpu_has_xsave && best->function == 0x1) {
5c404cab 69 best->ecx &= ~F(OSXSAVE);
00b27a3e 70 if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE))
5c404cab 71 best->ecx |= F(OSXSAVE);
00b27a3e
AK		 72 }
73
74 if (apic) {
5c404cab 75 if (best->ecx & F(TSC_DEADLINE_TIMER))
00b27a3e
AK		 76 apic->lapic_timer.timer_mode_mask = 3 << 17;
77 else
78 apic->lapic_timer.timer_mode_mask = 1 << 17;
79 }
f5132b01 80
d7876f1b 81 best = kvm_find_cpuid_entry(vcpu, 0xD, 0);
4344ee98 82 if (!best) {
d7876f1b 83 vcpu->arch.guest_supported_xcr0 = 0;
4344ee98
PB		 84 vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
85 } else {
d7876f1b
PB		 86 vcpu->arch.guest_supported_xcr0 =
87 (best->eax | ((u64)best->edx << 32)) &
4ff41732 88 kvm_supported_xcr0();
56c103ec
LJ		 89 vcpu->arch.guest_xstate_size = best->ebx =
90 xstate_required_size(vcpu->arch.xcr0);
4344ee98 91 }
d7876f1b 92
dd598091
NA		 93 /*
94 * The existing code assumes virtual address is 48-bit in the canonical
95 * address checks; exit if it is ever changed.
96 */
97 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
98 if (best && ((best->eax & 0xff00) >> 8) != 48 &&
99 ((best->eax & 0xff00) >> 8) != 0)
100 return -EINVAL;
101
f5132b01 102 kvm_pmu_cpuid_update(vcpu);
dd598091 103 return 0;
00b27a3e
AK		 104}
105
106static int is_efer_nx(void)
107{
108 unsigned long long efer = 0;
109
110 rdmsrl_safe(MSR_EFER, &efer);
111 return efer & EFER_NX;
112}
113
114static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu)
115{
116 int i;
117 struct kvm_cpuid_entry2 *e, *entry;
118
119 entry = NULL;
120 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
121 e = &vcpu->arch.cpuid_entries[i];
122 if (e->function == 0x80000001) {
123 entry = e;
124 break;
125 }
126 }
5c404cab
PB		 127 if (entry && (entry->edx & F(NX)) && !is_efer_nx()) {
128 entry->edx &= ~F(NX);
00b27a3e
AK		 129 printk(KERN_INFO "kvm: guest NX capability removed\n");
130 }
131}
132
133/* when an old userspace process fills a new kernel module */
134int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
135 struct kvm_cpuid *cpuid,
136 struct kvm_cpuid_entry __user *entries)
137{
138 int r, i;
139 struct kvm_cpuid_entry *cpuid_entries;
140
141 r = -E2BIG;
142 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
143 goto out;
144 r = -ENOMEM;
145 cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry) * cpuid->nent);
146 if (!cpuid_entries)
147 goto out;
148 r = -EFAULT;
149 if (copy_from_user(cpuid_entries, entries,
150 cpuid->nent * sizeof(struct kvm_cpuid_entry)))
151 goto out_free;
152 for (i = 0; i < cpuid->nent; i++) {
153 vcpu->arch.cpuid_entries[i].function = cpuid_entries[i].function;
154 vcpu->arch.cpuid_entries[i].eax = cpuid_entries[i].eax;
155 vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx;
156 vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx;
157 vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx;
158 vcpu->arch.cpuid_entries[i].index = 0;
159 vcpu->arch.cpuid_entries[i].flags = 0;
160 vcpu->arch.cpuid_entries[i].padding[0] = 0;
161 vcpu->arch.cpuid_entries[i].padding[1] = 0;
162 vcpu->arch.cpuid_entries[i].padding[2] = 0;
163 }
164 vcpu->arch.cpuid_nent = cpuid->nent;
165 cpuid_fix_nx_cap(vcpu);
00b27a3e
AK		 166 kvm_apic_set_version(vcpu);
167 kvm_x86_ops->cpuid_update(vcpu);
dd598091 168 r = kvm_update_cpuid(vcpu);
00b27a3e
AK		 169
170out_free:
171 vfree(cpuid_entries);
172out:
173 return r;
174}
175
176int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
177 struct kvm_cpuid2 *cpuid,
178 struct kvm_cpuid_entry2 __user *entries)
179{
180 int r;
181
182 r = -E2BIG;
183 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
184 goto out;
185 r = -EFAULT;
186 if (copy_from_user(&vcpu->arch.cpuid_entries, entries,
187 cpuid->nent * sizeof(struct kvm_cpuid_entry2)))
188 goto out;
189 vcpu->arch.cpuid_nent = cpuid->nent;
190 kvm_apic_set_version(vcpu);
191 kvm_x86_ops->cpuid_update(vcpu);
dd598091 192 r = kvm_update_cpuid(vcpu);
00b27a3e
AK		 193out:
194 return r;
195}
196
197int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
198 struct kvm_cpuid2 *cpuid,
199 struct kvm_cpuid_entry2 __user *entries)
200{
201 int r;
202
203 r = -E2BIG;
204 if (cpuid->nent < vcpu->arch.cpuid_nent)
205 goto out;
206 r = -EFAULT;
207 if (copy_to_user(entries, &vcpu->arch.cpuid_entries,
208 vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
209 goto out;
210 return 0;
211
212out:
213 cpuid->nent = vcpu->arch.cpuid_nent;
214 return r;
215}
216
217static void cpuid_mask(u32 *word, int wordnum)
218{
219 *word &= boot_cpu_data.x86_capability[wordnum];
220}
221
222static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function,
223 u32 index)
224{
225 entry->function = function;
226 entry->index = index;
227 cpuid_count(entry->function, entry->index,
228 &entry->eax, &entry->ebx, &entry->ecx, &entry->edx);
229 entry->flags = 0;
230}
231
9c15bb1d
BP		 232static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry,
233 u32 func, u32 index, int *nent, int maxnent)
234{
84cffe49
BP		 235 switch (func) {
236 case 0:
237 entry->eax = 1; /* only one leaf currently */
238 ++*nent;
239 break;
240 case 1:
241 entry->ecx = F(MOVBE);
242 ++*nent;
243 break;
244 default:
245 break;
246 }
247
248 entry->function = func;
249 entry->index = index;
250
9c15bb1d
BP		 251 return 0;
252}
253
254static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
255 u32 index, int *nent, int maxnent)
00b27a3e 256{
831bf664 257 int r;
00b27a3e
AK		 258 unsigned f_nx = is_efer_nx() ? F(NX) : 0;
259#ifdef CONFIG_X86_64
260 unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL)
261 ? F(GBPAGES) : 0;
262 unsigned f_lm = F(LM);
263#else
264 unsigned f_gbpages = 0;
265 unsigned f_lm = 0;
266#endif
267 unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0;
ad756a16 268 unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0;
93c4adc7 269 unsigned f_mpx = kvm_x86_ops->mpx_supported() ? F(MPX) : 0;
55412b2e 270 unsigned f_xsaves = kvm_x86_ops->xsaves_supported() ? F(XSAVES) : 0;
00b27a3e
AK		 271
272 /* cpuid 1.edx */
273 const u32 kvm_supported_word0_x86_features =
274 F(FPU) | F(VME) | F(DE) | F(PSE) |
275 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
276 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SEP) |
277 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
840d2830 278 F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLUSH) |
00b27a3e
AK		 279 0 /* Reserved, DS, ACPI */ | F(MMX) |
280 F(FXSR) | F(XMM) | F(XMM2) | F(SELFSNOOP) |
281 0 /* HTT, TM, Reserved, PBE */;
282 /* cpuid 0x80000001.edx */
283 const u32 kvm_supported_word1_x86_features =
284 F(FPU) | F(VME) | F(DE) | F(PSE) |
285 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
286 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SYSCALL) |
287 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
288 F(PAT) | F(PSE36) | 0 /* Reserved */ |
289 f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) |
290 F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp |
291 0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW);
292 /* cpuid 1.ecx */
293 const u32 kvm_supported_word4_x86_features =
87c00572
GS		 294 /* NOTE: MONITOR (and MWAIT) are emulated as NOP,
295 * but *not* advertised to guests via CPUID ! */
00b27a3e
AK		 296 F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ |
297 0 /* DS-CPL, VMX, SMX, EST */ |
298 0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ |
fb215366 299 F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ |
ad756a16 300 F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) |
00b27a3e
AK		 301 F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) |
302 0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) |
303 F(F16C) | F(RDRAND);
304 /* cpuid 0x80000001.ecx */
305 const u32 kvm_supported_word6_x86_features =
306 F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |
307 F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) |
2b036c6b 308 F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) |
00b27a3e
AK		 309 0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM);
310
311 /* cpuid 0xC0000001.edx */
312 const u32 kvm_supported_word5_x86_features =
313 F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) |
314 F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) |
315 F(PMM) | F(PMM_EN);
316
317 /* cpuid 7.0.ebx */
318 const u32 kvm_supported_word9_x86_features =
83c52915 319 F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) |
390bd528 320 F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) |
612263b3
CP		 321 F(ADX) | F(SMAP) | F(AVX512F) | F(AVX512PF) | F(AVX512ER) |
322 F(AVX512CD);
00b27a3e 323
b65d6e17
PB		 324 /* cpuid 0xD.1.eax */
325 const u32 kvm_supported_word10_x86_features =
55412b2e 326 F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | f_xsaves;
b65d6e17 327
00b27a3e
AK		 328 /* all calls to cpuid_count() should be made on the same cpu */
329 get_cpu();
831bf664
SL		 330
331 r = -E2BIG;
332
333 if (*nent >= maxnent)
334 goto out;
335
00b27a3e
AK		 336 do_cpuid_1_ent(entry, function, index);
337 ++*nent;
338
339 switch (function) {
340 case 0:
341 entry->eax = min(entry->eax, (u32)0xd);
342 break;
343 case 1:
344 entry->edx &= kvm_supported_word0_x86_features;
345 cpuid_mask(&entry->edx, 0);
346 entry->ecx &= kvm_supported_word4_x86_features;
347 cpuid_mask(&entry->ecx, 4);
348 /* we support x2apic emulation even if host does not support
349 * it since we emulate x2apic in software */
350 entry->ecx |= F(X2APIC);
351 break;
352 /* function 2 entries are STATEFUL. That is, repeated cpuid commands
353 * may return different values. This forces us to get_cpu() before
354 * issuing the first command, and also to emulate this annoying behavior
355 * in kvm_emulate_cpuid() using KVM_CPUID_FLAG_STATE_READ_NEXT */
356 case 2: {
357 int t, times = entry->eax & 0xff;
358
359 entry->flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
360 entry->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
831bf664
SL		 361 for (t = 1; t < times; ++t) {
362 if (*nent >= maxnent)
363 goto out;
364
00b27a3e
AK		 365 do_cpuid_1_ent(&entry[t], function, 0);
366 entry[t].flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
367 ++*nent;
368 }
369 break;
370 }
371 /* function 4 has additional index. */
372 case 4: {
373 int i, cache_type;
374
375 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
376 /* read more entries until cache_type is zero */
831bf664
SL		 377 for (i = 1; ; ++i) {
378 if (*nent >= maxnent)
379 goto out;
380
00b27a3e
AK		 381 cache_type = entry[i - 1].eax & 0x1f;
382 if (!cache_type)
383 break;
384 do_cpuid_1_ent(&entry[i], function, i);
385 entry[i].flags |=
386 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
387 ++*nent;
388 }
389 break;
390 }
391 case 7: {
392 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
bbbda795 393 /* Mask ebx against host capability word 9 */
00b27a3e
AK		 394 if (index == 0) {
395 entry->ebx &= kvm_supported_word9_x86_features;
396 cpuid_mask(&entry->ebx, 9);
ba904635
WA		 397 // TSC_ADJUST is emulated
398 entry->ebx |= F(TSC_ADJUST);
00b27a3e
AK		 399 } else
400 entry->ebx = 0;
401 entry->eax = 0;
402 entry->ecx = 0;
403 entry->edx = 0;
404 break;
405 }
406 case 9:
407 break;
a6c06ed1
GN		 408 case 0xa: { /* Architectural Performance Monitoring */
409 struct x86_pmu_capability cap;
410 union cpuid10_eax eax;
411 union cpuid10_edx edx;
412
413 perf_get_x86_pmu_capability(&cap);
414
415 /*
416 * Only support guest architectural pmu on a host
417 * with architectural pmu.
418 */
419 if (!cap.version)
420 memset(&cap, 0, sizeof(cap));
421
422 eax.split.version_id = min(cap.version, 2);
423 eax.split.num_counters = cap.num_counters_gp;
424 eax.split.bit_width = cap.bit_width_gp;
425 eax.split.mask_length = cap.events_mask_len;
426
427 edx.split.num_counters_fixed = cap.num_counters_fixed;
428 edx.split.bit_width_fixed = cap.bit_width_fixed;
429 edx.split.reserved = 0;
430
431 entry->eax = eax.full;
432 entry->ebx = cap.events_mask;
433 entry->ecx = 0;
434 entry->edx = edx.full;
435 break;
436 }
00b27a3e
AK		 437 /* function 0xb has additional index. */
438 case 0xb: {
439 int i, level_type;
440
441 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
442 /* read more entries until level_type is zero */
831bf664
SL		 443 for (i = 1; ; ++i) {
444 if (*nent >= maxnent)
445 goto out;
446
00b27a3e
AK		 447 level_type = entry[i - 1].ecx & 0xff00;
448 if (!level_type)
449 break;
450 do_cpuid_1_ent(&entry[i], function, i);
451 entry[i].flags |=
452 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
453 ++*nent;
454 }
455 break;
456 }
457 case 0xd: {
458 int idx, i;
4ff41732 459 u64 supported = kvm_supported_xcr0();
00b27a3e 460
4ff41732
PB		 461 entry->eax &= supported;
462 entry->edx &= supported >> 32;
00b27a3e 463 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
b65d6e17
PB		 464 if (!supported)
465 break;
466
831bf664 467 for (idx = 1, i = 1; idx < 64; ++idx) {
4ff41732 468 u64 mask = ((u64)1 << idx);
831bf664
SL		 469 if (*nent >= maxnent)
470 goto out;
471
00b27a3e 472 do_cpuid_1_ent(&entry[i], function, idx);
b65d6e17
PB		 473 if (idx == 1)
474 entry[i].eax &= kvm_supported_word10_x86_features;
475 else if (entry[i].eax == 0 || !(supported & mask))
00b27a3e
AK		 476 continue;
477 entry[i].flags |=
478 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
479 ++*nent;
480 ++i;
481 }
482 break;
483 }
484 case KVM_CPUID_SIGNATURE: {
326d07cb
MK		 485 static const char signature[12] = "KVMKVMKVM\0\0";
486 const u32 *sigptr = (const u32 *)signature;
57c22e5f 487 entry->eax = KVM_CPUID_FEATURES;
00b27a3e
AK		 488 entry->ebx = sigptr[0];
489 entry->ecx = sigptr[1];
490 entry->edx = sigptr[2];
491 break;
492 }
493 case KVM_CPUID_FEATURES:
494 entry->eax = (1 << KVM_FEATURE_CLOCKSOURCE) |
495 (1 << KVM_FEATURE_NOP_IO_DELAY) |
496 (1 << KVM_FEATURE_CLOCKSOURCE2) |
497 (1 << KVM_FEATURE_ASYNC_PF) |
ae7a2a3f 498 (1 << KVM_FEATURE_PV_EOI) |
6aef266c
SV		 499 (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) |
500 (1 << KVM_FEATURE_PV_UNHALT);
00b27a3e
AK		 501
502 if (sched_info_on())
503 entry->eax |= (1 << KVM_FEATURE_STEAL_TIME);
504
505 entry->ebx = 0;
506 entry->ecx = 0;
507 entry->edx = 0;
508 break;
509 case 0x80000000:
510 entry->eax = min(entry->eax, 0x8000001a);
511 break;
512 case 0x80000001:
513 entry->edx &= kvm_supported_word1_x86_features;
514 cpuid_mask(&entry->edx, 1);
515 entry->ecx &= kvm_supported_word6_x86_features;
516 cpuid_mask(&entry->ecx, 6);
517 break;
e4c9a5a1
MT		 518 case 0x80000007: /* Advanced power management */
519 /* invariant TSC is CPUID.80000007H:EDX[8] */
520 entry->edx &= (1 << 8);
521 /* mask against host */
522 entry->edx &= boot_cpu_data.x86_power;
523 entry->eax = entry->ebx = entry->ecx = 0;
524 break;
00b27a3e
AK		 525 case 0x80000008: {
526 unsigned g_phys_as = (entry->eax >> 16) & 0xff;
527 unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U);
528 unsigned phys_as = entry->eax & 0xff;
529
530 if (!g_phys_as)
531 g_phys_as = phys_as;
532 entry->eax = g_phys_as | (virt_as << 8);
533 entry->ebx = entry->edx = 0;
534 break;
535 }
536 case 0x80000019:
537 entry->ecx = entry->edx = 0;
538 break;
539 case 0x8000001a:
540 break;
541 case 0x8000001d:
542 break;
543 /*Add support for Centaur's CPUID instruction*/
544 case 0xC0000000:
545 /*Just support up to 0xC0000004 now*/
546 entry->eax = min(entry->eax, 0xC0000004);
547 break;
548 case 0xC0000001:
549 entry->edx &= kvm_supported_word5_x86_features;
550 cpuid_mask(&entry->edx, 5);
551 break;
552 case 3: /* Processor serial number */
553 case 5: /* MONITOR/MWAIT */
554 case 6: /* Thermal management */
00b27a3e
AK		 555 case 0xC0000002:
556 case 0xC0000003:
557 case 0xC0000004:
558 default:
559 entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
560 break;
561 }
562
563 kvm_x86_ops->set_supported_cpuid(function, entry);
564
831bf664
SL		 565 r = 0;
566
567out:
00b27a3e 568 put_cpu();
831bf664
SL		 569
570 return r;
00b27a3e
AK		 571}
572
9c15bb1d
BP		 573static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 func,
574 u32 idx, int *nent, int maxnent, unsigned int type)
575{
576 if (type == KVM_GET_EMULATED_CPUID)
577 return __do_cpuid_ent_emulated(entry, func, idx, nent, maxnent);
578
579 return __do_cpuid_ent(entry, func, idx, nent, maxnent);
580}
581
00b27a3e
AK		 582#undef F
583
831bf664
SL		 584struct kvm_cpuid_param {
585 u32 func;
586 u32 idx;
587 bool has_leaf_count;
326d07cb 588 bool (*qualifier)(const struct kvm_cpuid_param *param);
831bf664
SL		 589};
590
326d07cb 591static bool is_centaur_cpu(const struct kvm_cpuid_param *param)
831bf664
SL		 592{
593 return boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR;
594}
595
9c15bb1d
BP		 596static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries,
597 __u32 num_entries, unsigned int ioctl_type)
598{
599 int i;
1b2ca422 600 __u32 pad[3];
9c15bb1d
BP		 601
602 if (ioctl_type != KVM_GET_EMULATED_CPUID)
603 return false;
604
605 /*
606 * We want to make sure that ->padding is being passed clean from
607 * userspace in case we want to use it for something in the future.
608 *
609 * Sadly, this wasn't enforced for KVM_GET_SUPPORTED_CPUID and so we
610 * have to give ourselves satisfied only with the emulated side. /me
611 * sheds a tear.
612 */
613 for (i = 0; i < num_entries; i++) {
1b2ca422
BP		 614 if (copy_from_user(pad, entries[i].padding, sizeof(pad)))
615 return true;
616
617 if (pad[0] || pad[1] || pad[2])
9c15bb1d
BP		 618 return true;
619 }
620 return false;
621}
622
623int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
624 struct kvm_cpuid_entry2 __user *entries,
625 unsigned int type)
00b27a3e
AK		 626{
627 struct kvm_cpuid_entry2 *cpuid_entries;
831bf664 628 int limit, nent = 0, r = -E2BIG, i;
00b27a3e 629 u32 func;
326d07cb 630 static const struct kvm_cpuid_param param[] = {
831bf664
SL		 631 { .func = 0, .has_leaf_count = true },
632 { .func = 0x80000000, .has_leaf_count = true },
633 { .func = 0xC0000000, .qualifier = is_centaur_cpu, .has_leaf_count = true },
634 { .func = KVM_CPUID_SIGNATURE },
635 { .func = KVM_CPUID_FEATURES },
636 };
00b27a3e
AK		 637
638 if (cpuid->nent < 1)
639 goto out;
640 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
641 cpuid->nent = KVM_MAX_CPUID_ENTRIES;
9c15bb1d
BP		 642
643 if (sanity_check_entries(entries, cpuid->nent, type))
644 return -EINVAL;
645
00b27a3e 646 r = -ENOMEM;
84cffe49 647 cpuid_entries = vzalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
00b27a3e
AK		 648 if (!cpuid_entries)
649 goto out;
650
831bf664
SL		 651 r = 0;
652 for (i = 0; i < ARRAY_SIZE(param); i++) {
326d07cb 653 const struct kvm_cpuid_param *ent = &param[i];
00b27a3e 654
831bf664
SL		 655 if (ent->qualifier && !ent->qualifier(ent))
656 continue;
00b27a3e 657
831bf664 658 r = do_cpuid_ent(&cpuid_entries[nent], ent->func, ent->idx,
9c15bb1d 659 &nent, cpuid->nent, type);
00b27a3e 660
831bf664 661 if (r)
00b27a3e
AK		 662 goto out_free;
663
831bf664
SL		 664 if (!ent->has_leaf_count)
665 continue;
666
00b27a3e 667 limit = cpuid_entries[nent - 1].eax;
831bf664
SL		 668 for (func = ent->func + 1; func <= limit && nent < cpuid->nent && r == 0; ++func)
669 r = do_cpuid_ent(&cpuid_entries[nent], func, ent->idx,
9c15bb1d 670 &nent, cpuid->nent, type);
00b27a3e 671
831bf664 672 if (r)
00b27a3e
AK		 673 goto out_free;
674 }
675
00b27a3e
AK		 676 r = -EFAULT;
677 if (copy_to_user(entries, cpuid_entries,
678 nent * sizeof(struct kvm_cpuid_entry2)))
679 goto out_free;
680 cpuid->nent = nent;
681 r = 0;
682
683out_free:
684 vfree(cpuid_entries);
685out:
686 return r;
687}
688
689static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i)
690{
691 struct kvm_cpuid_entry2 *e = &vcpu->arch.cpuid_entries[i];
692 int j, nent = vcpu->arch.cpuid_nent;
693
694 e->flags &= ~KVM_CPUID_FLAG_STATE_READ_NEXT;
695 /* when no next entry is found, the current entry[i] is reselected */
696 for (j = i + 1; ; j = (j + 1) % nent) {
697 struct kvm_cpuid_entry2 *ej = &vcpu->arch.cpuid_entries[j];
698 if (ej->function == e->function) {
699 ej->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
700 return j;
701 }
702 }
703 return 0; /* silence gcc, even though control never reaches here */
704}
705
706/* find an entry with matching function, matching index (if needed), and that
707 * should be read next (if it's stateful) */
708static int is_matching_cpuid_entry(struct kvm_cpuid_entry2 *e,
709 u32 function, u32 index)
710{
711 if (e->function != function)
712 return 0;
713 if ((e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) && e->index != index)
714 return 0;
715 if ((e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) &&
716 !(e->flags & KVM_CPUID_FLAG_STATE_READ_NEXT))
717 return 0;
718 return 1;
719}
720
721struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
722 u32 function, u32 index)
723{
724 int i;
725 struct kvm_cpuid_entry2 *best = NULL;
726
727 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
728 struct kvm_cpuid_entry2 *e;
729
730 e = &vcpu->arch.cpuid_entries[i];
731 if (is_matching_cpuid_entry(e, function, index)) {
732 if (e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC)
733 move_to_next_stateful_cpuid_entry(vcpu, i);
734 best = e;
735 break;
736 }
737 }
738 return best;
739}
740EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);
741
742int cpuid_maxphyaddr(struct kvm_vcpu *vcpu)
743{
744 struct kvm_cpuid_entry2 *best;
745
746 best = kvm_find_cpuid_entry(vcpu, 0x80000000, 0);
747 if (!best || best->eax < 0x80000008)
748 goto not_found;
749 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
750 if (best)
751 return best->eax & 0xff;
752not_found:
753 return 36;
754}
3573e22c 755EXPORT_SYMBOL_GPL(cpuid_maxphyaddr);
00b27a3e
AK		 756
757/*
758 * If no match is found, check whether we exceed the vCPU's limit
759 * and return the content of the highest valid _standard_ leaf instead.
760 * This is to satisfy the CPUID specification.
761 */
762static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu,
763 u32 function, u32 index)
764{
765 struct kvm_cpuid_entry2 *maxlevel;
766
767 maxlevel = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0);
768 if (!maxlevel || maxlevel->eax >= function)
769 return NULL;
770 if (function & 0x80000000) {
771 maxlevel = kvm_find_cpuid_entry(vcpu, 0, 0);
772 if (!maxlevel)
773 return NULL;
774 }
775 return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index);
776}
777
62046e5a 778void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx)
00b27a3e 779{
62046e5a 780 u32 function = *eax, index = *ecx;
00b27a3e
AK		 781 struct kvm_cpuid_entry2 *best;
782
00b27a3e
AK		 783 best = kvm_find_cpuid_entry(vcpu, function, index);
784
785 if (!best)
786 best = check_cpuid_limit(vcpu, function, index);
787
bc613494
MT		 788 /*
789 * Perfmon not yet supported for L2 guest.
790 */
791 if (is_guest_mode(vcpu) && function == 0xa)
792 best = NULL;
793
00b27a3e 794 if (best) {
62046e5a
AK		 795 *eax = best->eax;
796 *ebx = best->ebx;
797 *ecx = best->ecx;
798 *edx = best->edx;
799 } else
800 *eax = *ebx = *ecx = *edx = 0;
a9d4e439 801 trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx);
62046e5a 802}
66f7b72e 803EXPORT_SYMBOL_GPL(kvm_cpuid);
62046e5a
AK		 804
805void kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
806{
807 u32 function, eax, ebx, ecx, edx;
808
809 function = eax = kvm_register_read(vcpu, VCPU_REGS_RAX);
810 ecx = kvm_register_read(vcpu, VCPU_REGS_RCX);
811 kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx);
812 kvm_register_write(vcpu, VCPU_REGS_RAX, eax);
813 kvm_register_write(vcpu, VCPU_REGS_RBX, ebx);
814 kvm_register_write(vcpu, VCPU_REGS_RCX, ecx);
815 kvm_register_write(vcpu, VCPU_REGS_RDX, edx);
00b27a3e 816 kvm_x86_ops->skip_emulated_instruction(vcpu);
00b27a3e
AK		 817}
818EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);
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