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arm64: defconfig: defconfig update for 3.19
[linux/fpc-iii.git] / arch / x86 / kvm / cpuid.c
blob8a80737ee6e6ec14bc7d9a6ffe08d9f580d3c890
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>
17 #include <linux/vmalloc.h>
18 #include <linux/uaccess.h>
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
26 static u32 xstate_required_size(u64 xstate_bv, bool compacted)
27 {
28 int feature_bit = 0;
29 u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
30
31 xstate_bv &= XSTATE_EXTEND_MASK;
32 while (xstate_bv) {
33 if (xstate_bv & 0x1) {
34 u32 eax, ebx, ecx, edx, offset;
35 cpuid_count(0xD, feature_bit, &eax, &ebx, &ecx, &edx);
36 offset = compacted ? ret : ebx;
37 ret = max(ret, offset + eax);
38 }
39
40 xstate_bv >>= 1;
41 feature_bit++;
42 }
43
44 return ret;
45 }
46
47 u64 kvm_supported_xcr0(void)
48 {
49 u64 xcr0 = KVM_SUPPORTED_XCR0 & host_xcr0;
50
51 if (!kvm_x86_ops->mpx_supported())
52 xcr0 &= ~(XSTATE_BNDREGS | XSTATE_BNDCSR);
53
54 return xcr0;
55 }
56
57 #define F(x) bit(X86_FEATURE_##x)
58
59 int kvm_update_cpuid(struct kvm_vcpu *vcpu)
60 {
61 struct kvm_cpuid_entry2 *best;
62 struct kvm_lapic *apic = vcpu->arch.apic;
63
64 best = kvm_find_cpuid_entry(vcpu, 1, 0);
65 if (!best)
66 return 0;
67
68 /* Update OSXSAVE bit */
69 if (cpu_has_xsave && best->function == 0x1) {
70 best->ecx &= ~F(OSXSAVE);
71 if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE))
72 best->ecx |= F(OSXSAVE);
73 }
74
75 if (apic) {
76 if (best->ecx & F(TSC_DEADLINE_TIMER))
77 apic->lapic_timer.timer_mode_mask = 3 << 17;
78 else
79 apic->lapic_timer.timer_mode_mask = 1 << 17;
80 }
81
82 best = kvm_find_cpuid_entry(vcpu, 0xD, 0);
83 if (!best) {
84 vcpu->arch.guest_supported_xcr0 = 0;
85 vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
86 } else {
87 vcpu->arch.guest_supported_xcr0 =
88 (best->eax | ((u64)best->edx << 32)) &
89 kvm_supported_xcr0();
90 vcpu->arch.guest_xstate_size = best->ebx =
91 xstate_required_size(vcpu->arch.xcr0, false);
92 }
93
94 best = kvm_find_cpuid_entry(vcpu, 0xD, 1);
95 if (best && (best->eax & (F(XSAVES) | F(XSAVEC))))
96 best->ebx = xstate_required_size(vcpu->arch.xcr0, true);
97
98 /*
99 * The existing code assumes virtual address is 48-bit in the canonical
100 * address checks; exit if it is ever changed.
101 */
102 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
103 if (best && ((best->eax & 0xff00) >> 8) != 48 &&
104 ((best->eax & 0xff00) >> 8) != 0)
105 return -EINVAL;
106
107 kvm_pmu_cpuid_update(vcpu);
108 return 0;
109 }
110
111 static int is_efer_nx(void)
112 {
113 unsigned long long efer = 0;
114
115 rdmsrl_safe(MSR_EFER, &efer);
116 return efer & EFER_NX;
117 }
118
119 static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu)
120 {
121 int i;
122 struct kvm_cpuid_entry2 *e, *entry;
123
124 entry = NULL;
125 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
126 e = &vcpu->arch.cpuid_entries[i];
127 if (e->function == 0x80000001) {
128 entry = e;
129 break;
130 }
131 }
132 if (entry && (entry->edx & F(NX)) && !is_efer_nx()) {
133 entry->edx &= ~F(NX);
134 printk(KERN_INFO "kvm: guest NX capability removed\n");
135 }
136 }
137
138 /* when an old userspace process fills a new kernel module */
139 int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
140 struct kvm_cpuid *cpuid,
141 struct kvm_cpuid_entry __user *entries)
142 {
143 int r, i;
144 struct kvm_cpuid_entry *cpuid_entries;
145
146 r = -E2BIG;
147 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
148 goto out;
149 r = -ENOMEM;
150 cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry) * cpuid->nent);
151 if (!cpuid_entries)
152 goto out;
153 r = -EFAULT;
154 if (copy_from_user(cpuid_entries, entries,
155 cpuid->nent * sizeof(struct kvm_cpuid_entry)))
156 goto out_free;
157 for (i = 0; i < cpuid->nent; i++) {
158 vcpu->arch.cpuid_entries[i].function = cpuid_entries[i].function;
159 vcpu->arch.cpuid_entries[i].eax = cpuid_entries[i].eax;
160 vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx;
161 vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx;
162 vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx;
163 vcpu->arch.cpuid_entries[i].index = 0;
164 vcpu->arch.cpuid_entries[i].flags = 0;
165 vcpu->arch.cpuid_entries[i].padding[0] = 0;
166 vcpu->arch.cpuid_entries[i].padding[1] = 0;
167 vcpu->arch.cpuid_entries[i].padding[2] = 0;
168 }
169 vcpu->arch.cpuid_nent = cpuid->nent;
170 cpuid_fix_nx_cap(vcpu);
171 kvm_apic_set_version(vcpu);
172 kvm_x86_ops->cpuid_update(vcpu);
173 r = kvm_update_cpuid(vcpu);
174
175 out_free:
176 vfree(cpuid_entries);
177 out:
178 return r;
179 }
180
181 int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
182 struct kvm_cpuid2 *cpuid,
183 struct kvm_cpuid_entry2 __user *entries)
184 {
185 int r;
186
187 r = -E2BIG;
188 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
189 goto out;
190 r = -EFAULT;
191 if (copy_from_user(&vcpu->arch.cpuid_entries, entries,
192 cpuid->nent * sizeof(struct kvm_cpuid_entry2)))
193 goto out;
194 vcpu->arch.cpuid_nent = cpuid->nent;
195 kvm_apic_set_version(vcpu);
196 kvm_x86_ops->cpuid_update(vcpu);
197 r = kvm_update_cpuid(vcpu);
198 out:
199 return r;
200 }
201
202 int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
203 struct kvm_cpuid2 *cpuid,
204 struct kvm_cpuid_entry2 __user *entries)
205 {
206 int r;
207
208 r = -E2BIG;
209 if (cpuid->nent < vcpu->arch.cpuid_nent)
210 goto out;
211 r = -EFAULT;
212 if (copy_to_user(entries, &vcpu->arch.cpuid_entries,
213 vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
214 goto out;
215 return 0;
216
217 out:
218 cpuid->nent = vcpu->arch.cpuid_nent;
219 return r;
220 }
221
222 static void cpuid_mask(u32 *word, int wordnum)
223 {
224 *word &= boot_cpu_data.x86_capability[wordnum];
225 }
226
227 static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function,
228 u32 index)
229 {
230 entry->function = function;
231 entry->index = index;
232 cpuid_count(entry->function, entry->index,
233 &entry->eax, &entry->ebx, &entry->ecx, &entry->edx);
234 entry->flags = 0;
235 }
236
237 static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry,
238 u32 func, u32 index, int *nent, int maxnent)
239 {
240 switch (func) {
241 case 0:
242 entry->eax = 1; /* only one leaf currently */
243 ++*nent;
244 break;
245 case 1:
246 entry->ecx = F(MOVBE);
247 ++*nent;
248 break;
249 default:
250 break;
251 }
252
253 entry->function = func;
254 entry->index = index;
255
256 return 0;
257 }
258
259 static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
260 u32 index, int *nent, int maxnent)
261 {
262 int r;
263 unsigned f_nx = is_efer_nx() ? F(NX) : 0;
264 #ifdef CONFIG_X86_64
265 unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL)
266 ? F(GBPAGES) : 0;
267 unsigned f_lm = F(LM);
268 #else
269 unsigned f_gbpages = 0;
270 unsigned f_lm = 0;
271 #endif
272 unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0;
273 unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0;
274 unsigned f_mpx = kvm_x86_ops->mpx_supported() ? F(MPX) : 0;
275 unsigned f_xsaves = kvm_x86_ops->xsaves_supported() ? F(XSAVES) : 0;
276
277 /* cpuid 1.edx */
278 const u32 kvm_supported_word0_x86_features =
279 F(FPU) | F(VME) | F(DE) | F(PSE) |
280 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
281 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SEP) |
282 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
283 F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLUSH) |
284 0 /* Reserved, DS, ACPI */ | F(MMX) |
285 F(FXSR) | F(XMM) | F(XMM2) | F(SELFSNOOP) |
286 0 /* HTT, TM, Reserved, PBE */;
287 /* cpuid 0x80000001.edx */
288 const u32 kvm_supported_word1_x86_features =
289 F(FPU) | F(VME) | F(DE) | F(PSE) |
290 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
291 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SYSCALL) |
292 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
293 F(PAT) | F(PSE36) | 0 /* Reserved */ |
294 f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) |
295 F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp |
296 0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW);
297 /* cpuid 1.ecx */
298 const u32 kvm_supported_word4_x86_features =
299 /* NOTE: MONITOR (and MWAIT) are emulated as NOP,
300 * but *not* advertised to guests via CPUID ! */
301 F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ |
302 0 /* DS-CPL, VMX, SMX, EST */ |
303 0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ |
304 F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ |
305 F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) |
306 F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) |
307 0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) |
308 F(F16C) | F(RDRAND);
309 /* cpuid 0x80000001.ecx */
310 const u32 kvm_supported_word6_x86_features =
311 F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |
312 F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) |
313 F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) |
314 0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM);
315
316 /* cpuid 0xC0000001.edx */
317 const u32 kvm_supported_word5_x86_features =
318 F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) |
319 F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) |
320 F(PMM) | F(PMM_EN);
321
322 /* cpuid 7.0.ebx */
323 const u32 kvm_supported_word9_x86_features =
324 F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) |
325 F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) |
326 F(ADX) | F(SMAP) | F(AVX512F) | F(AVX512PF) | F(AVX512ER) |
327 F(AVX512CD);
328
329 /* cpuid 0xD.1.eax */
330 const u32 kvm_supported_word10_x86_features =
331 F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | f_xsaves;
332
333 /* all calls to cpuid_count() should be made on the same cpu */
334 get_cpu();
335
336 r = -E2BIG;
337
338 if (*nent >= maxnent)
339 goto out;
340
341 do_cpuid_1_ent(entry, function, index);
342 ++*nent;
343
344 switch (function) {
345 case 0:
346 entry->eax = min(entry->eax, (u32)0xd);
347 break;
348 case 1:
349 entry->edx &= kvm_supported_word0_x86_features;
350 cpuid_mask(&entry->edx, 0);
351 entry->ecx &= kvm_supported_word4_x86_features;
352 cpuid_mask(&entry->ecx, 4);
353 /* we support x2apic emulation even if host does not support
354 * it since we emulate x2apic in software */
355 entry->ecx |= F(X2APIC);
356 break;
357 /* function 2 entries are STATEFUL. That is, repeated cpuid commands
358 * may return different values. This forces us to get_cpu() before
359 * issuing the first command, and also to emulate this annoying behavior
360 * in kvm_emulate_cpuid() using KVM_CPUID_FLAG_STATE_READ_NEXT */
361 case 2: {
362 int t, times = entry->eax & 0xff;
363
364 entry->flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
365 entry->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
366 for (t = 1; t < times; ++t) {
367 if (*nent >= maxnent)
368 goto out;
369
370 do_cpuid_1_ent(&entry[t], function, 0);
371 entry[t].flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
372 ++*nent;
373 }
374 break;
375 }
376 /* function 4 has additional index. */
377 case 4: {
378 int i, cache_type;
379
380 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
381 /* read more entries until cache_type is zero */
382 for (i = 1; ; ++i) {
383 if (*nent >= maxnent)
384 goto out;
385
386 cache_type = entry[i - 1].eax & 0x1f;
387 if (!cache_type)
388 break;
389 do_cpuid_1_ent(&entry[i], function, i);
390 entry[i].flags |=
391 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
392 ++*nent;
393 }
394 break;
395 }
396 case 7: {
397 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
398 /* Mask ebx against host capability word 9 */
399 if (index == 0) {
400 entry->ebx &= kvm_supported_word9_x86_features;
401 cpuid_mask(&entry->ebx, 9);
402 // TSC_ADJUST is emulated
403 entry->ebx |= F(TSC_ADJUST);
404 } else
405 entry->ebx = 0;
406 entry->eax = 0;
407 entry->ecx = 0;
408 entry->edx = 0;
409 break;
410 }
411 case 9:
412 break;
413 case 0xa: { /* Architectural Performance Monitoring */
414 struct x86_pmu_capability cap;
415 union cpuid10_eax eax;
416 union cpuid10_edx edx;
417
418 perf_get_x86_pmu_capability(&cap);
419
420 /*
421 * Only support guest architectural pmu on a host
422 * with architectural pmu.
423 */
424 if (!cap.version)
425 memset(&cap, 0, sizeof(cap));
426
427 eax.split.version_id = min(cap.version, 2);
428 eax.split.num_counters = cap.num_counters_gp;
429 eax.split.bit_width = cap.bit_width_gp;
430 eax.split.mask_length = cap.events_mask_len;
431
432 edx.split.num_counters_fixed = cap.num_counters_fixed;
433 edx.split.bit_width_fixed = cap.bit_width_fixed;
434 edx.split.reserved = 0;
435
436 entry->eax = eax.full;
437 entry->ebx = cap.events_mask;
438 entry->ecx = 0;
439 entry->edx = edx.full;
440 break;
441 }
442 /* function 0xb has additional index. */
443 case 0xb: {
444 int i, level_type;
445
446 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
447 /* read more entries until level_type is zero */
448 for (i = 1; ; ++i) {
449 if (*nent >= maxnent)
450 goto out;
451
452 level_type = entry[i - 1].ecx & 0xff00;
453 if (!level_type)
454 break;
455 do_cpuid_1_ent(&entry[i], function, i);
456 entry[i].flags |=
457 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
458 ++*nent;
459 }
460 break;
461 }
462 case 0xd: {
463 int idx, i;
464 u64 supported = kvm_supported_xcr0();
465
466 entry->eax &= supported;
467 entry->ebx = xstate_required_size(supported, false);
468 entry->ecx = entry->ebx;
469 entry->edx &= supported >> 32;
470 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
471 if (!supported)
472 break;
473
474 for (idx = 1, i = 1; idx < 64; ++idx) {
475 u64 mask = ((u64)1 << idx);
476 if (*nent >= maxnent)
477 goto out;
478
479 do_cpuid_1_ent(&entry[i], function, idx);
480 if (idx == 1) {
481 entry[i].eax &= kvm_supported_word10_x86_features;
482 entry[i].ebx = 0;
483 if (entry[i].eax & (F(XSAVES)|F(XSAVEC)))
484 entry[i].ebx =
485 xstate_required_size(supported,
486 true);
487 } else {
488 if (entry[i].eax == 0 || !(supported & mask))
489 continue;
490 if (WARN_ON_ONCE(entry[i].ecx & 1))
491 continue;
492 }
493 entry[i].ecx = 0;
494 entry[i].edx = 0;
495 entry[i].flags |=
496 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
497 ++*nent;
498 ++i;
499 }
500 break;
501 }
502 case KVM_CPUID_SIGNATURE: {
503 static const char signature[12] = "KVMKVMKVM\0\0";
504 const u32 *sigptr = (const u32 *)signature;
505 entry->eax = KVM_CPUID_FEATURES;
506 entry->ebx = sigptr[0];
507 entry->ecx = sigptr[1];
508 entry->edx = sigptr[2];
509 break;
510 }
511 case KVM_CPUID_FEATURES:
512 entry->eax = (1 << KVM_FEATURE_CLOCKSOURCE) |
513 (1 << KVM_FEATURE_NOP_IO_DELAY) |
514 (1 << KVM_FEATURE_CLOCKSOURCE2) |
515 (1 << KVM_FEATURE_ASYNC_PF) |
516 (1 << KVM_FEATURE_PV_EOI) |
517 (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) |
518 (1 << KVM_FEATURE_PV_UNHALT);
519
520 if (sched_info_on())
521 entry->eax |= (1 << KVM_FEATURE_STEAL_TIME);
522
523 entry->ebx = 0;
524 entry->ecx = 0;
525 entry->edx = 0;
526 break;
527 case 0x80000000:
528 entry->eax = min(entry->eax, 0x8000001a);
529 break;
530 case 0x80000001:
531 entry->edx &= kvm_supported_word1_x86_features;
532 cpuid_mask(&entry->edx, 1);
533 entry->ecx &= kvm_supported_word6_x86_features;
534 cpuid_mask(&entry->ecx, 6);
535 break;
536 case 0x80000007: /* Advanced power management */
537 /* invariant TSC is CPUID.80000007H:EDX[8] */
538 entry->edx &= (1 << 8);
539 /* mask against host */
540 entry->edx &= boot_cpu_data.x86_power;
541 entry->eax = entry->ebx = entry->ecx = 0;
542 break;
543 case 0x80000008: {
544 unsigned g_phys_as = (entry->eax >> 16) & 0xff;
545 unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U);
546 unsigned phys_as = entry->eax & 0xff;
547
548 if (!g_phys_as)
549 g_phys_as = phys_as;
550 entry->eax = g_phys_as | (virt_as << 8);
551 entry->ebx = entry->edx = 0;
552 break;
553 }
554 case 0x80000019:
555 entry->ecx = entry->edx = 0;
556 break;
557 case 0x8000001a:
558 break;
559 case 0x8000001d:
560 break;
561 /*Add support for Centaur's CPUID instruction*/
562 case 0xC0000000:
563 /*Just support up to 0xC0000004 now*/
564 entry->eax = min(entry->eax, 0xC0000004);
565 break;
566 case 0xC0000001:
567 entry->edx &= kvm_supported_word5_x86_features;
568 cpuid_mask(&entry->edx, 5);
569 break;
570 case 3: /* Processor serial number */
571 case 5: /* MONITOR/MWAIT */
572 case 6: /* Thermal management */
573 case 0xC0000002:
574 case 0xC0000003:
575 case 0xC0000004:
576 default:
577 entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
578 break;
579 }
580
581 kvm_x86_ops->set_supported_cpuid(function, entry);
582
583 r = 0;
584
585 out:
586 put_cpu();
587
588 return r;
589 }
590
591 static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 func,
592 u32 idx, int *nent, int maxnent, unsigned int type)
593 {
594 if (type == KVM_GET_EMULATED_CPUID)
595 return __do_cpuid_ent_emulated(entry, func, idx, nent, maxnent);
596
597 return __do_cpuid_ent(entry, func, idx, nent, maxnent);
598 }
599
600 #undef F
601
602 struct kvm_cpuid_param {
603 u32 func;
604 u32 idx;
605 bool has_leaf_count;
606 bool (*qualifier)(const struct kvm_cpuid_param *param);
607 };
608
609 static bool is_centaur_cpu(const struct kvm_cpuid_param *param)
610 {
611 return boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR;
612 }
613
614 static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries,
615 __u32 num_entries, unsigned int ioctl_type)
616 {
617 int i;
618 __u32 pad[3];
619
620 if (ioctl_type != KVM_GET_EMULATED_CPUID)
621 return false;
622
623 /*
624 * We want to make sure that ->padding is being passed clean from
625 * userspace in case we want to use it for something in the future.
626 *
627 * Sadly, this wasn't enforced for KVM_GET_SUPPORTED_CPUID and so we
628 * have to give ourselves satisfied only with the emulated side. /me
629 * sheds a tear.
630 */
631 for (i = 0; i < num_entries; i++) {
632 if (copy_from_user(pad, entries[i].padding, sizeof(pad)))
633 return true;
634
635 if (pad[0] || pad[1] || pad[2])
636 return true;
637 }
638 return false;
639 }
640
641 int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
642 struct kvm_cpuid_entry2 __user *entries,
643 unsigned int type)
644 {
645 struct kvm_cpuid_entry2 *cpuid_entries;
646 int limit, nent = 0, r = -E2BIG, i;
647 u32 func;
648 static const struct kvm_cpuid_param param[] = {
649 { .func = 0, .has_leaf_count = true },
650 { .func = 0x80000000, .has_leaf_count = true },
651 { .func = 0xC0000000, .qualifier = is_centaur_cpu, .has_leaf_count = true },
652 { .func = KVM_CPUID_SIGNATURE },
653 { .func = KVM_CPUID_FEATURES },
654 };
655
656 if (cpuid->nent < 1)
657 goto out;
658 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
659 cpuid->nent = KVM_MAX_CPUID_ENTRIES;
660
661 if (sanity_check_entries(entries, cpuid->nent, type))
662 return -EINVAL;
663
664 r = -ENOMEM;
665 cpuid_entries = vzalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
666 if (!cpuid_entries)
667 goto out;
668
669 r = 0;
670 for (i = 0; i < ARRAY_SIZE(param); i++) {
671 const struct kvm_cpuid_param *ent = &param[i];
672
673 if (ent->qualifier && !ent->qualifier(ent))
674 continue;
675
676 r = do_cpuid_ent(&cpuid_entries[nent], ent->func, ent->idx,
677 &nent, cpuid->nent, type);
678
679 if (r)
680 goto out_free;
681
682 if (!ent->has_leaf_count)
683 continue;
684
685 limit = cpuid_entries[nent - 1].eax;
686 for (func = ent->func + 1; func <= limit && nent < cpuid->nent && r == 0; ++func)
687 r = do_cpuid_ent(&cpuid_entries[nent], func, ent->idx,
688 &nent, cpuid->nent, type);
689
690 if (r)
691 goto out_free;
692 }
693
694 r = -EFAULT;
695 if (copy_to_user(entries, cpuid_entries,
696 nent * sizeof(struct kvm_cpuid_entry2)))
697 goto out_free;
698 cpuid->nent = nent;
699 r = 0;
700
701 out_free:
702 vfree(cpuid_entries);
703 out:
704 return r;
705 }
706
707 static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i)
708 {
709 struct kvm_cpuid_entry2 *e = &vcpu->arch.cpuid_entries[i];
710 int j, nent = vcpu->arch.cpuid_nent;
711
712 e->flags &= ~KVM_CPUID_FLAG_STATE_READ_NEXT;
713 /* when no next entry is found, the current entry[i] is reselected */
714 for (j = i + 1; ; j = (j + 1) % nent) {
715 struct kvm_cpuid_entry2 *ej = &vcpu->arch.cpuid_entries[j];
716 if (ej->function == e->function) {
717 ej->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
718 return j;
719 }
720 }
721 return 0; /* silence gcc, even though control never reaches here */
722 }
723
724 /* find an entry with matching function, matching index (if needed), and that
725 * should be read next (if it's stateful) */
726 static int is_matching_cpuid_entry(struct kvm_cpuid_entry2 *e,
727 u32 function, u32 index)
728 {
729 if (e->function != function)
730 return 0;
731 if ((e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) && e->index != index)
732 return 0;
733 if ((e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) &&
734 !(e->flags & KVM_CPUID_FLAG_STATE_READ_NEXT))
735 return 0;
736 return 1;
737 }
738
739 struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
740 u32 function, u32 index)
741 {
742 int i;
743 struct kvm_cpuid_entry2 *best = NULL;
744
745 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
746 struct kvm_cpuid_entry2 *e;
747
748 e = &vcpu->arch.cpuid_entries[i];
749 if (is_matching_cpuid_entry(e, function, index)) {
750 if (e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC)
751 move_to_next_stateful_cpuid_entry(vcpu, i);
752 best = e;
753 break;
754 }
755 }
756 return best;
757 }
758 EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);
759
760 int cpuid_maxphyaddr(struct kvm_vcpu *vcpu)
761 {
762 struct kvm_cpuid_entry2 *best;
763
764 best = kvm_find_cpuid_entry(vcpu, 0x80000000, 0);
765 if (!best || best->eax < 0x80000008)
766 goto not_found;
767 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
768 if (best)
769 return best->eax & 0xff;
770 not_found:
771 return 36;
772 }
773 EXPORT_SYMBOL_GPL(cpuid_maxphyaddr);
774
775 /*
776 * If no match is found, check whether we exceed the vCPU's limit
777 * and return the content of the highest valid _standard_ leaf instead.
778 * This is to satisfy the CPUID specification.
779 */
780 static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu,
781 u32 function, u32 index)
782 {
783 struct kvm_cpuid_entry2 *maxlevel;
784
785 maxlevel = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0);
786 if (!maxlevel || maxlevel->eax >= function)
787 return NULL;
788 if (function & 0x80000000) {
789 maxlevel = kvm_find_cpuid_entry(vcpu, 0, 0);
790 if (!maxlevel)
791 return NULL;
792 }
793 return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index);
794 }
795
796 void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx)
797 {
798 u32 function = *eax, index = *ecx;
799 struct kvm_cpuid_entry2 *best;
800
801 best = kvm_find_cpuid_entry(vcpu, function, index);
802
803 if (!best)
804 best = check_cpuid_limit(vcpu, function, index);
805
806 /*
807 * Perfmon not yet supported for L2 guest.
808 */
809 if (is_guest_mode(vcpu) && function == 0xa)
810 best = NULL;
811
812 if (best) {
813 *eax = best->eax;
814 *ebx = best->ebx;
815 *ecx = best->ecx;
816 *edx = best->edx;
817 } else
818 *eax = *ebx = *ecx = *edx = 0;
819 trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx);
820 }
821 EXPORT_SYMBOL_GPL(kvm_cpuid);
822
823 void kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
824 {
825 u32 function, eax, ebx, ecx, edx;
826
827 function = eax = kvm_register_read(vcpu, VCPU_REGS_RAX);
828 ecx = kvm_register_read(vcpu, VCPU_REGS_RCX);
829 kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx);
830 kvm_register_write(vcpu, VCPU_REGS_RAX, eax);
831 kvm_register_write(vcpu, VCPU_REGS_RBX, ebx);
832 kvm_register_write(vcpu, VCPU_REGS_RCX, ecx);
833 kvm_register_write(vcpu, VCPU_REGS_RDX, edx);
834 kvm_x86_ops->skip_emulated_instruction(vcpu);
835 }
836 EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);
Linux with added FPC-III support