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x86/xen: Audit and remove any unnecessary uses of module.h
[mirror_ubuntu-bionic-kernel.git] / arch / x86 / kvm / cpuid.c
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/fpu/internal.h> /* For use_eager_fpu. Ugh! */
20 #include <asm/user.h>
21 #include <asm/fpu/xstate.h>
22 #include "cpuid.h"
23 #include "lapic.h"
24 #include "mmu.h"
25 #include "trace.h"
26 #include "pmu.h"
27
28 static u32 xstate_required_size(u64 xstate_bv, bool compacted)
29 {
30 int feature_bit = 0;
31 u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
32
33 xstate_bv &= XFEATURE_MASK_EXTEND;
34 while (xstate_bv) {
35 if (xstate_bv & 0x1) {
36 u32 eax, ebx, ecx, edx, offset;
37 cpuid_count(0xD, feature_bit, &eax, &ebx, &ecx, &edx);
38 offset = compacted ? ret : ebx;
39 ret = max(ret, offset + eax);
40 }
41
42 xstate_bv >>= 1;
43 feature_bit++;
44 }
45
46 return ret;
47 }
48
49 bool kvm_mpx_supported(void)
50 {
51 return ((host_xcr0 & (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR))
52 && kvm_x86_ops->mpx_supported());
53 }
54 EXPORT_SYMBOL_GPL(kvm_mpx_supported);
55
56 u64 kvm_supported_xcr0(void)
57 {
58 u64 xcr0 = KVM_SUPPORTED_XCR0 & host_xcr0;
59
60 if (!kvm_mpx_supported())
61 xcr0 &= ~(XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR);
62
63 return xcr0;
64 }
65
66 #define F(x) bit(X86_FEATURE_##x)
67
68 int kvm_update_cpuid(struct kvm_vcpu *vcpu)
69 {
70 struct kvm_cpuid_entry2 *best;
71 struct kvm_lapic *apic = vcpu->arch.apic;
72
73 best = kvm_find_cpuid_entry(vcpu, 1, 0);
74 if (!best)
75 return 0;
76
77 /* Update OSXSAVE bit */
78 if (boot_cpu_has(X86_FEATURE_XSAVE) && best->function == 0x1) {
79 best->ecx &= ~F(OSXSAVE);
80 if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE))
81 best->ecx |= F(OSXSAVE);
82 }
83
84 if (apic) {
85 if (best->ecx & F(TSC_DEADLINE_TIMER))
86 apic->lapic_timer.timer_mode_mask = 3 << 17;
87 else
88 apic->lapic_timer.timer_mode_mask = 1 << 17;
89 }
90
91 best = kvm_find_cpuid_entry(vcpu, 7, 0);
92 if (best) {
93 /* Update OSPKE bit */
94 if (boot_cpu_has(X86_FEATURE_PKU) && best->function == 0x7) {
95 best->ecx &= ~F(OSPKE);
96 if (kvm_read_cr4_bits(vcpu, X86_CR4_PKE))
97 best->ecx |= F(OSPKE);
98 }
99 }
100
101 best = kvm_find_cpuid_entry(vcpu, 0xD, 0);
102 if (!best) {
103 vcpu->arch.guest_supported_xcr0 = 0;
104 vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
105 } else {
106 vcpu->arch.guest_supported_xcr0 =
107 (best->eax | ((u64)best->edx << 32)) &
108 kvm_supported_xcr0();
109 vcpu->arch.guest_xstate_size = best->ebx =
110 xstate_required_size(vcpu->arch.xcr0, false);
111 }
112
113 best = kvm_find_cpuid_entry(vcpu, 0xD, 1);
114 if (best && (best->eax & (F(XSAVES) | F(XSAVEC))))
115 best->ebx = xstate_required_size(vcpu->arch.xcr0, true);
116
117 if (use_eager_fpu())
118 kvm_x86_ops->fpu_activate(vcpu);
119
120 /*
121 * The existing code assumes virtual address is 48-bit in the canonical
122 * address checks; exit if it is ever changed.
123 */
124 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
125 if (best && ((best->eax & 0xff00) >> 8) != 48 &&
126 ((best->eax & 0xff00) >> 8) != 0)
127 return -EINVAL;
128
129 /* Update physical-address width */
130 vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
131
132 kvm_pmu_refresh(vcpu);
133 return 0;
134 }
135
136 static int is_efer_nx(void)
137 {
138 unsigned long long efer = 0;
139
140 rdmsrl_safe(MSR_EFER, &efer);
141 return efer & EFER_NX;
142 }
143
144 static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu)
145 {
146 int i;
147 struct kvm_cpuid_entry2 *e, *entry;
148
149 entry = NULL;
150 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
151 e = &vcpu->arch.cpuid_entries[i];
152 if (e->function == 0x80000001) {
153 entry = e;
154 break;
155 }
156 }
157 if (entry && (entry->edx & F(NX)) && !is_efer_nx()) {
158 entry->edx &= ~F(NX);
159 printk(KERN_INFO "kvm: guest NX capability removed\n");
160 }
161 }
162
163 int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu)
164 {
165 struct kvm_cpuid_entry2 *best;
166
167 best = kvm_find_cpuid_entry(vcpu, 0x80000000, 0);
168 if (!best || best->eax < 0x80000008)
169 goto not_found;
170 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
171 if (best)
172 return best->eax & 0xff;
173 not_found:
174 return 36;
175 }
176 EXPORT_SYMBOL_GPL(cpuid_query_maxphyaddr);
177
178 /* when an old userspace process fills a new kernel module */
179 int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
180 struct kvm_cpuid *cpuid,
181 struct kvm_cpuid_entry __user *entries)
182 {
183 int r, i;
184 struct kvm_cpuid_entry *cpuid_entries = NULL;
185
186 r = -E2BIG;
187 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
188 goto out;
189 r = -ENOMEM;
190 if (cpuid->nent) {
191 cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry) *
192 cpuid->nent);
193 if (!cpuid_entries)
194 goto out;
195 r = -EFAULT;
196 if (copy_from_user(cpuid_entries, entries,
197 cpuid->nent * sizeof(struct kvm_cpuid_entry)))
198 goto out;
199 }
200 for (i = 0; i < cpuid->nent; i++) {
201 vcpu->arch.cpuid_entries[i].function = cpuid_entries[i].function;
202 vcpu->arch.cpuid_entries[i].eax = cpuid_entries[i].eax;
203 vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx;
204 vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx;
205 vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx;
206 vcpu->arch.cpuid_entries[i].index = 0;
207 vcpu->arch.cpuid_entries[i].flags = 0;
208 vcpu->arch.cpuid_entries[i].padding[0] = 0;
209 vcpu->arch.cpuid_entries[i].padding[1] = 0;
210 vcpu->arch.cpuid_entries[i].padding[2] = 0;
211 }
212 vcpu->arch.cpuid_nent = cpuid->nent;
213 cpuid_fix_nx_cap(vcpu);
214 kvm_apic_set_version(vcpu);
215 kvm_x86_ops->cpuid_update(vcpu);
216 r = kvm_update_cpuid(vcpu);
217
218 out:
219 vfree(cpuid_entries);
220 return r;
221 }
222
223 int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
224 struct kvm_cpuid2 *cpuid,
225 struct kvm_cpuid_entry2 __user *entries)
226 {
227 int r;
228
229 r = -E2BIG;
230 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
231 goto out;
232 r = -EFAULT;
233 if (copy_from_user(&vcpu->arch.cpuid_entries, entries,
234 cpuid->nent * sizeof(struct kvm_cpuid_entry2)))
235 goto out;
236 vcpu->arch.cpuid_nent = cpuid->nent;
237 kvm_apic_set_version(vcpu);
238 kvm_x86_ops->cpuid_update(vcpu);
239 r = kvm_update_cpuid(vcpu);
240 out:
241 return r;
242 }
243
244 int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
245 struct kvm_cpuid2 *cpuid,
246 struct kvm_cpuid_entry2 __user *entries)
247 {
248 int r;
249
250 r = -E2BIG;
251 if (cpuid->nent < vcpu->arch.cpuid_nent)
252 goto out;
253 r = -EFAULT;
254 if (copy_to_user(entries, &vcpu->arch.cpuid_entries,
255 vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
256 goto out;
257 return 0;
258
259 out:
260 cpuid->nent = vcpu->arch.cpuid_nent;
261 return r;
262 }
263
264 static void cpuid_mask(u32 *word, int wordnum)
265 {
266 *word &= boot_cpu_data.x86_capability[wordnum];
267 }
268
269 static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function,
270 u32 index)
271 {
272 entry->function = function;
273 entry->index = index;
274 cpuid_count(entry->function, entry->index,
275 &entry->eax, &entry->ebx, &entry->ecx, &entry->edx);
276 entry->flags = 0;
277 }
278
279 static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry,
280 u32 func, u32 index, int *nent, int maxnent)
281 {
282 switch (func) {
283 case 0:
284 entry->eax = 1; /* only one leaf currently */
285 ++*nent;
286 break;
287 case 1:
288 entry->ecx = F(MOVBE);
289 ++*nent;
290 break;
291 default:
292 break;
293 }
294
295 entry->function = func;
296 entry->index = index;
297
298 return 0;
299 }
300
301 static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
302 u32 index, int *nent, int maxnent)
303 {
304 int r;
305 unsigned f_nx = is_efer_nx() ? F(NX) : 0;
306 #ifdef CONFIG_X86_64
307 unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL)
308 ? F(GBPAGES) : 0;
309 unsigned f_lm = F(LM);
310 #else
311 unsigned f_gbpages = 0;
312 unsigned f_lm = 0;
313 #endif
314 unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0;
315 unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0;
316 unsigned f_mpx = kvm_mpx_supported() ? F(MPX) : 0;
317 unsigned f_xsaves = kvm_x86_ops->xsaves_supported() ? F(XSAVES) : 0;
318
319 /* cpuid 1.edx */
320 const u32 kvm_cpuid_1_edx_x86_features =
321 F(FPU) | F(VME) | F(DE) | F(PSE) |
322 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
323 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SEP) |
324 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
325 F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLUSH) |
326 0 /* Reserved, DS, ACPI */ | F(MMX) |
327 F(FXSR) | F(XMM) | F(XMM2) | F(SELFSNOOP) |
328 0 /* HTT, TM, Reserved, PBE */;
329 /* cpuid 0x80000001.edx */
330 const u32 kvm_cpuid_8000_0001_edx_x86_features =
331 F(FPU) | F(VME) | F(DE) | F(PSE) |
332 F(TSC) | F(MSR) | F(PAE) | F(MCE) |
333 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SYSCALL) |
334 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
335 F(PAT) | F(PSE36) | 0 /* Reserved */ |
336 f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) |
337 F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp |
338 0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW);
339 /* cpuid 1.ecx */
340 const u32 kvm_cpuid_1_ecx_x86_features =
341 /* NOTE: MONITOR (and MWAIT) are emulated as NOP,
342 * but *not* advertised to guests via CPUID ! */
343 F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ |
344 0 /* DS-CPL, VMX, SMX, EST */ |
345 0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ |
346 F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ |
347 F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) |
348 F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) |
349 0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) |
350 F(F16C) | F(RDRAND);
351 /* cpuid 0x80000001.ecx */
352 const u32 kvm_cpuid_8000_0001_ecx_x86_features =
353 F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ |
354 F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) |
355 F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) |
356 0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM);
357
358 /* cpuid 0xC0000001.edx */
359 const u32 kvm_cpuid_C000_0001_edx_x86_features =
360 F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) |
361 F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) |
362 F(PMM) | F(PMM_EN);
363
364 /* cpuid 7.0.ebx */
365 const u32 kvm_cpuid_7_0_ebx_x86_features =
366 F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) |
367 F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) |
368 F(ADX) | F(SMAP) | F(AVX512F) | F(AVX512PF) | F(AVX512ER) |
369 F(AVX512CD) | F(CLFLUSHOPT) | F(CLWB) | F(PCOMMIT);
370
371 /* cpuid 0xD.1.eax */
372 const u32 kvm_cpuid_D_1_eax_x86_features =
373 F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | f_xsaves;
374
375 /* cpuid 7.0.ecx*/
376 const u32 kvm_cpuid_7_0_ecx_x86_features = F(PKU) | 0 /*OSPKE*/;
377
378 /* all calls to cpuid_count() should be made on the same cpu */
379 get_cpu();
380
381 r = -E2BIG;
382
383 if (*nent >= maxnent)
384 goto out;
385
386 do_cpuid_1_ent(entry, function, index);
387 ++*nent;
388
389 switch (function) {
390 case 0:
391 entry->eax = min(entry->eax, (u32)0xd);
392 break;
393 case 1:
394 entry->edx &= kvm_cpuid_1_edx_x86_features;
395 cpuid_mask(&entry->edx, CPUID_1_EDX);
396 entry->ecx &= kvm_cpuid_1_ecx_x86_features;
397 cpuid_mask(&entry->ecx, CPUID_1_ECX);
398 /* we support x2apic emulation even if host does not support
399 * it since we emulate x2apic in software */
400 entry->ecx |= F(X2APIC);
401 break;
402 /* function 2 entries are STATEFUL. That is, repeated cpuid commands
403 * may return different values. This forces us to get_cpu() before
404 * issuing the first command, and also to emulate this annoying behavior
405 * in kvm_emulate_cpuid() using KVM_CPUID_FLAG_STATE_READ_NEXT */
406 case 2: {
407 int t, times = entry->eax & 0xff;
408
409 entry->flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
410 entry->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
411 for (t = 1; t < times; ++t) {
412 if (*nent >= maxnent)
413 goto out;
414
415 do_cpuid_1_ent(&entry[t], function, 0);
416 entry[t].flags |= KVM_CPUID_FLAG_STATEFUL_FUNC;
417 ++*nent;
418 }
419 break;
420 }
421 /* function 4 has additional index. */
422 case 4: {
423 int i, cache_type;
424
425 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
426 /* read more entries until cache_type is zero */
427 for (i = 1; ; ++i) {
428 if (*nent >= maxnent)
429 goto out;
430
431 cache_type = entry[i - 1].eax & 0x1f;
432 if (!cache_type)
433 break;
434 do_cpuid_1_ent(&entry[i], function, i);
435 entry[i].flags |=
436 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
437 ++*nent;
438 }
439 break;
440 }
441 case 6: /* Thermal management */
442 entry->eax = 0x4; /* allow ARAT */
443 entry->ebx = 0;
444 entry->ecx = 0;
445 entry->edx = 0;
446 break;
447 case 7: {
448 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
449 /* Mask ebx against host capability word 9 */
450 if (index == 0) {
451 entry->ebx &= kvm_cpuid_7_0_ebx_x86_features;
452 cpuid_mask(&entry->ebx, CPUID_7_0_EBX);
453 // TSC_ADJUST is emulated
454 entry->ebx |= F(TSC_ADJUST);
455 entry->ecx &= kvm_cpuid_7_0_ecx_x86_features;
456 cpuid_mask(&entry->ecx, CPUID_7_ECX);
457 /* PKU is not yet implemented for shadow paging. */
458 if (!tdp_enabled)
459 entry->ecx &= ~F(PKU);
460 } else {
461 entry->ebx = 0;
462 entry->ecx = 0;
463 }
464 entry->eax = 0;
465 entry->edx = 0;
466 break;
467 }
468 case 9:
469 break;
470 case 0xa: { /* Architectural Performance Monitoring */
471 struct x86_pmu_capability cap;
472 union cpuid10_eax eax;
473 union cpuid10_edx edx;
474
475 perf_get_x86_pmu_capability(&cap);
476
477 /*
478 * Only support guest architectural pmu on a host
479 * with architectural pmu.
480 */
481 if (!cap.version)
482 memset(&cap, 0, sizeof(cap));
483
484 eax.split.version_id = min(cap.version, 2);
485 eax.split.num_counters = cap.num_counters_gp;
486 eax.split.bit_width = cap.bit_width_gp;
487 eax.split.mask_length = cap.events_mask_len;
488
489 edx.split.num_counters_fixed = cap.num_counters_fixed;
490 edx.split.bit_width_fixed = cap.bit_width_fixed;
491 edx.split.reserved = 0;
492
493 entry->eax = eax.full;
494 entry->ebx = cap.events_mask;
495 entry->ecx = 0;
496 entry->edx = edx.full;
497 break;
498 }
499 /* function 0xb has additional index. */
500 case 0xb: {
501 int i, level_type;
502
503 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
504 /* read more entries until level_type is zero */
505 for (i = 1; ; ++i) {
506 if (*nent >= maxnent)
507 goto out;
508
509 level_type = entry[i - 1].ecx & 0xff00;
510 if (!level_type)
511 break;
512 do_cpuid_1_ent(&entry[i], function, i);
513 entry[i].flags |=
514 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
515 ++*nent;
516 }
517 break;
518 }
519 case 0xd: {
520 int idx, i;
521 u64 supported = kvm_supported_xcr0();
522
523 entry->eax &= supported;
524 entry->ebx = xstate_required_size(supported, false);
525 entry->ecx = entry->ebx;
526 entry->edx &= supported >> 32;
527 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
528 if (!supported)
529 break;
530
531 for (idx = 1, i = 1; idx < 64; ++idx) {
532 u64 mask = ((u64)1 << idx);
533 if (*nent >= maxnent)
534 goto out;
535
536 do_cpuid_1_ent(&entry[i], function, idx);
537 if (idx == 1) {
538 entry[i].eax &= kvm_cpuid_D_1_eax_x86_features;
539 cpuid_mask(&entry[i].eax, CPUID_D_1_EAX);
540 entry[i].ebx = 0;
541 if (entry[i].eax & (F(XSAVES)|F(XSAVEC)))
542 entry[i].ebx =
543 xstate_required_size(supported,
544 true);
545 } else {
546 if (entry[i].eax == 0 || !(supported & mask))
547 continue;
548 if (WARN_ON_ONCE(entry[i].ecx & 1))
549 continue;
550 }
551 entry[i].ecx = 0;
552 entry[i].edx = 0;
553 entry[i].flags |=
554 KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
555 ++*nent;
556 ++i;
557 }
558 break;
559 }
560 case KVM_CPUID_SIGNATURE: {
561 static const char signature[12] = "KVMKVMKVM\0\0";
562 const u32 *sigptr = (const u32 *)signature;
563 entry->eax = KVM_CPUID_FEATURES;
564 entry->ebx = sigptr[0];
565 entry->ecx = sigptr[1];
566 entry->edx = sigptr[2];
567 break;
568 }
569 case KVM_CPUID_FEATURES:
570 entry->eax = (1 << KVM_FEATURE_CLOCKSOURCE) |
571 (1 << KVM_FEATURE_NOP_IO_DELAY) |
572 (1 << KVM_FEATURE_CLOCKSOURCE2) |
573 (1 << KVM_FEATURE_ASYNC_PF) |
574 (1 << KVM_FEATURE_PV_EOI) |
575 (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) |
576 (1 << KVM_FEATURE_PV_UNHALT);
577
578 if (sched_info_on())
579 entry->eax |= (1 << KVM_FEATURE_STEAL_TIME);
580
581 entry->ebx = 0;
582 entry->ecx = 0;
583 entry->edx = 0;
584 break;
585 case 0x80000000:
586 entry->eax = min(entry->eax, 0x8000001a);
587 break;
588 case 0x80000001:
589 entry->edx &= kvm_cpuid_8000_0001_edx_x86_features;
590 cpuid_mask(&entry->edx, CPUID_8000_0001_EDX);
591 entry->ecx &= kvm_cpuid_8000_0001_ecx_x86_features;
592 cpuid_mask(&entry->ecx, CPUID_8000_0001_ECX);
593 break;
594 case 0x80000007: /* Advanced power management */
595 /* invariant TSC is CPUID.80000007H:EDX[8] */
596 entry->edx &= (1 << 8);
597 /* mask against host */
598 entry->edx &= boot_cpu_data.x86_power;
599 entry->eax = entry->ebx = entry->ecx = 0;
600 break;
601 case 0x80000008: {
602 unsigned g_phys_as = (entry->eax >> 16) & 0xff;
603 unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U);
604 unsigned phys_as = entry->eax & 0xff;
605
606 if (!g_phys_as)
607 g_phys_as = phys_as;
608 entry->eax = g_phys_as | (virt_as << 8);
609 entry->ebx = entry->edx = 0;
610 break;
611 }
612 case 0x80000019:
613 entry->ecx = entry->edx = 0;
614 break;
615 case 0x8000001a:
616 break;
617 case 0x8000001d:
618 break;
619 /*Add support for Centaur's CPUID instruction*/
620 case 0xC0000000:
621 /*Just support up to 0xC0000004 now*/
622 entry->eax = min(entry->eax, 0xC0000004);
623 break;
624 case 0xC0000001:
625 entry->edx &= kvm_cpuid_C000_0001_edx_x86_features;
626 cpuid_mask(&entry->edx, CPUID_C000_0001_EDX);
627 break;
628 case 3: /* Processor serial number */
629 case 5: /* MONITOR/MWAIT */
630 case 0xC0000002:
631 case 0xC0000003:
632 case 0xC0000004:
633 default:
634 entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
635 break;
636 }
637
638 kvm_x86_ops->set_supported_cpuid(function, entry);
639
640 r = 0;
641
642 out:
643 put_cpu();
644
645 return r;
646 }
647
648 static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 func,
649 u32 idx, int *nent, int maxnent, unsigned int type)
650 {
651 if (type == KVM_GET_EMULATED_CPUID)
652 return __do_cpuid_ent_emulated(entry, func, idx, nent, maxnent);
653
654 return __do_cpuid_ent(entry, func, idx, nent, maxnent);
655 }
656
657 #undef F
658
659 struct kvm_cpuid_param {
660 u32 func;
661 u32 idx;
662 bool has_leaf_count;
663 bool (*qualifier)(const struct kvm_cpuid_param *param);
664 };
665
666 static bool is_centaur_cpu(const struct kvm_cpuid_param *param)
667 {
668 return boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR;
669 }
670
671 static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries,
672 __u32 num_entries, unsigned int ioctl_type)
673 {
674 int i;
675 __u32 pad[3];
676
677 if (ioctl_type != KVM_GET_EMULATED_CPUID)
678 return false;
679
680 /*
681 * We want to make sure that ->padding is being passed clean from
682 * userspace in case we want to use it for something in the future.
683 *
684 * Sadly, this wasn't enforced for KVM_GET_SUPPORTED_CPUID and so we
685 * have to give ourselves satisfied only with the emulated side. /me
686 * sheds a tear.
687 */
688 for (i = 0; i < num_entries; i++) {
689 if (copy_from_user(pad, entries[i].padding, sizeof(pad)))
690 return true;
691
692 if (pad[0] || pad[1] || pad[2])
693 return true;
694 }
695 return false;
696 }
697
698 int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
699 struct kvm_cpuid_entry2 __user *entries,
700 unsigned int type)
701 {
702 struct kvm_cpuid_entry2 *cpuid_entries;
703 int limit, nent = 0, r = -E2BIG, i;
704 u32 func;
705 static const struct kvm_cpuid_param param[] = {
706 { .func = 0, .has_leaf_count = true },
707 { .func = 0x80000000, .has_leaf_count = true },
708 { .func = 0xC0000000, .qualifier = is_centaur_cpu, .has_leaf_count = true },
709 { .func = KVM_CPUID_SIGNATURE },
710 { .func = KVM_CPUID_FEATURES },
711 };
712
713 if (cpuid->nent < 1)
714 goto out;
715 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
716 cpuid->nent = KVM_MAX_CPUID_ENTRIES;
717
718 if (sanity_check_entries(entries, cpuid->nent, type))
719 return -EINVAL;
720
721 r = -ENOMEM;
722 cpuid_entries = vzalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
723 if (!cpuid_entries)
724 goto out;
725
726 r = 0;
727 for (i = 0; i < ARRAY_SIZE(param); i++) {
728 const struct kvm_cpuid_param *ent = &param[i];
729
730 if (ent->qualifier && !ent->qualifier(ent))
731 continue;
732
733 r = do_cpuid_ent(&cpuid_entries[nent], ent->func, ent->idx,
734 &nent, cpuid->nent, type);
735
736 if (r)
737 goto out_free;
738
739 if (!ent->has_leaf_count)
740 continue;
741
742 limit = cpuid_entries[nent - 1].eax;
743 for (func = ent->func + 1; func <= limit && nent < cpuid->nent && r == 0; ++func)
744 r = do_cpuid_ent(&cpuid_entries[nent], func, ent->idx,
745 &nent, cpuid->nent, type);
746
747 if (r)
748 goto out_free;
749 }
750
751 r = -EFAULT;
752 if (copy_to_user(entries, cpuid_entries,
753 nent * sizeof(struct kvm_cpuid_entry2)))
754 goto out_free;
755 cpuid->nent = nent;
756 r = 0;
757
758 out_free:
759 vfree(cpuid_entries);
760 out:
761 return r;
762 }
763
764 static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i)
765 {
766 struct kvm_cpuid_entry2 *e = &vcpu->arch.cpuid_entries[i];
767 int j, nent = vcpu->arch.cpuid_nent;
768
769 e->flags &= ~KVM_CPUID_FLAG_STATE_READ_NEXT;
770 /* when no next entry is found, the current entry[i] is reselected */
771 for (j = i + 1; ; j = (j + 1) % nent) {
772 struct kvm_cpuid_entry2 *ej = &vcpu->arch.cpuid_entries[j];
773 if (ej->function == e->function) {
774 ej->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT;
775 return j;
776 }
777 }
778 return 0; /* silence gcc, even though control never reaches here */
779 }
780
781 /* find an entry with matching function, matching index (if needed), and that
782 * should be read next (if it's stateful) */
783 static int is_matching_cpuid_entry(struct kvm_cpuid_entry2 *e,
784 u32 function, u32 index)
785 {
786 if (e->function != function)
787 return 0;
788 if ((e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) && e->index != index)
789 return 0;
790 if ((e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) &&
791 !(e->flags & KVM_CPUID_FLAG_STATE_READ_NEXT))
792 return 0;
793 return 1;
794 }
795
796 struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
797 u32 function, u32 index)
798 {
799 int i;
800 struct kvm_cpuid_entry2 *best = NULL;
801
802 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) {
803 struct kvm_cpuid_entry2 *e;
804
805 e = &vcpu->arch.cpuid_entries[i];
806 if (is_matching_cpuid_entry(e, function, index)) {
807 if (e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC)
808 move_to_next_stateful_cpuid_entry(vcpu, i);
809 best = e;
810 break;
811 }
812 }
813 return best;
814 }
815 EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);
816
817 /*
818 * If no match is found, check whether we exceed the vCPU's limit
819 * and return the content of the highest valid _standard_ leaf instead.
820 * This is to satisfy the CPUID specification.
821 */
822 static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu,
823 u32 function, u32 index)
824 {
825 struct kvm_cpuid_entry2 *maxlevel;
826
827 maxlevel = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0);
828 if (!maxlevel || maxlevel->eax >= function)
829 return NULL;
830 if (function & 0x80000000) {
831 maxlevel = kvm_find_cpuid_entry(vcpu, 0, 0);
832 if (!maxlevel)
833 return NULL;
834 }
835 return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index);
836 }
837
838 void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx)
839 {
840 u32 function = *eax, index = *ecx;
841 struct kvm_cpuid_entry2 *best;
842
843 best = kvm_find_cpuid_entry(vcpu, function, index);
844
845 if (!best)
846 best = check_cpuid_limit(vcpu, function, index);
847
848 /*
849 * Perfmon not yet supported for L2 guest.
850 */
851 if (is_guest_mode(vcpu) && function == 0xa)
852 best = NULL;
853
854 if (best) {
855 *eax = best->eax;
856 *ebx = best->ebx;
857 *ecx = best->ecx;
858 *edx = best->edx;
859 } else
860 *eax = *ebx = *ecx = *edx = 0;
861 trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx);
862 }
863 EXPORT_SYMBOL_GPL(kvm_cpuid);
864
865 void kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
866 {
867 u32 function, eax, ebx, ecx, edx;
868
869 function = eax = kvm_register_read(vcpu, VCPU_REGS_RAX);
870 ecx = kvm_register_read(vcpu, VCPU_REGS_RCX);
871 kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx);
872 kvm_register_write(vcpu, VCPU_REGS_RAX, eax);
873 kvm_register_write(vcpu, VCPU_REGS_RBX, ebx);
874 kvm_register_write(vcpu, VCPU_REGS_RCX, ecx);
875 kvm_register_write(vcpu, VCPU_REGS_RDX, edx);
876 kvm_x86_ops->skip_emulated_instruction(vcpu);
877 }
878 EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);
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