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/export.h> 17 #include <linux/vmalloc.h> 18 #include <linux/uaccess.h> 19 #include <asm/processor.h> 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 /* These are scattered features in cpufeatures.h. */ 69 #define KVM_CPUID_BIT_AVX512_4VNNIW 2 70 #define KVM_CPUID_BIT_AVX512_4FMAPS 3 71 #define KF(x) bit(KVM_CPUID_BIT_##x) 72 73 int kvm_update_cpuid(struct kvm_vcpu *vcpu) 74 { 75 struct kvm_cpuid_entry2 *best; 76 struct kvm_lapic *apic = vcpu->arch.apic; 77 78 best = kvm_find_cpuid_entry(vcpu, 1, 0); 79 if (!best) 80 return 0; 81 82 /* Update OSXSAVE bit */ 83 if (boot_cpu_has(X86_FEATURE_XSAVE) && best->function == 0x1) { 84 best->ecx &= ~F(OSXSAVE); 85 if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE)) 86 best->ecx |= F(OSXSAVE); 87 } 88 89 best->edx &= ~F(APIC); 90 if (vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE) 91 best->edx |= F(APIC); 92 93 if (apic) { 94 if (best->ecx & F(TSC_DEADLINE_TIMER)) 95 apic->lapic_timer.timer_mode_mask = 3 << 17; 96 else 97 apic->lapic_timer.timer_mode_mask = 1 << 17; 98 } 99 100 best = kvm_find_cpuid_entry(vcpu, 7, 0); 101 if (best) { 102 /* Update OSPKE bit */ 103 if (boot_cpu_has(X86_FEATURE_PKU) && best->function == 0x7) { 104 best->ecx &= ~F(OSPKE); 105 if (kvm_read_cr4_bits(vcpu, X86_CR4_PKE)) 106 best->ecx |= F(OSPKE); 107 } 108 } 109 110 best = kvm_find_cpuid_entry(vcpu, 0xD, 0); 111 if (!best) { 112 vcpu->arch.guest_supported_xcr0 = 0; 113 vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET; 114 } else { 115 vcpu->arch.guest_supported_xcr0 = 116 (best->eax | ((u64)best->edx << 32)) & 117 kvm_supported_xcr0(); 118 vcpu->arch.guest_xstate_size = best->ebx = 119 xstate_required_size(vcpu->arch.xcr0, false); 120 } 121 122 best = kvm_find_cpuid_entry(vcpu, 0xD, 1); 123 if (best && (best->eax & (F(XSAVES) | F(XSAVEC)))) 124 best->ebx = xstate_required_size(vcpu->arch.xcr0, true); 125 126 /* 127 * The existing code assumes virtual address is 48-bit in the canonical 128 * address checks; exit if it is ever changed. 129 */ 130 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0); 131 if (best && ((best->eax & 0xff00) >> 8) != 48 && 132 ((best->eax & 0xff00) >> 8) != 0) 133 return -EINVAL; 134 135 /* Update physical-address width */ 136 vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu); 137 138 kvm_pmu_refresh(vcpu); 139 return 0; 140 } 141 142 static int is_efer_nx(void) 143 { 144 unsigned long long efer = 0; 145 146 rdmsrl_safe(MSR_EFER, &efer); 147 return efer & EFER_NX; 148 } 149 150 static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu) 151 { 152 int i; 153 struct kvm_cpuid_entry2 *e, *entry; 154 155 entry = NULL; 156 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) { 157 e = &vcpu->arch.cpuid_entries[i]; 158 if (e->function == 0x80000001) { 159 entry = e; 160 break; 161 } 162 } 163 if (entry && (entry->edx & F(NX)) && !is_efer_nx()) { 164 entry->edx &= ~F(NX); 165 printk(KERN_INFO "kvm: guest NX capability removed\n"); 166 } 167 } 168 169 int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu) 170 { 171 struct kvm_cpuid_entry2 *best; 172 173 best = kvm_find_cpuid_entry(vcpu, 0x80000000, 0); 174 if (!best || best->eax < 0x80000008) 175 goto not_found; 176 best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0); 177 if (best) 178 return best->eax & 0xff; 179 not_found: 180 return 36; 181 } 182 EXPORT_SYMBOL_GPL(cpuid_query_maxphyaddr); 183 184 /* when an old userspace process fills a new kernel module */ 185 int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu, 186 struct kvm_cpuid *cpuid, 187 struct kvm_cpuid_entry __user *entries) 188 { 189 int r, i; 190 struct kvm_cpuid_entry *cpuid_entries = NULL; 191 192 r = -E2BIG; 193 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES) 194 goto out; 195 r = -ENOMEM; 196 if (cpuid->nent) { 197 cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry) * 198 cpuid->nent); 199 if (!cpuid_entries) 200 goto out; 201 r = -EFAULT; 202 if (copy_from_user(cpuid_entries, entries, 203 cpuid->nent * sizeof(struct kvm_cpuid_entry))) 204 goto out; 205 } 206 for (i = 0; i < cpuid->nent; i++) { 207 vcpu->arch.cpuid_entries[i].function = cpuid_entries[i].function; 208 vcpu->arch.cpuid_entries[i].eax = cpuid_entries[i].eax; 209 vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx; 210 vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx; 211 vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx; 212 vcpu->arch.cpuid_entries[i].index = 0; 213 vcpu->arch.cpuid_entries[i].flags = 0; 214 vcpu->arch.cpuid_entries[i].padding[0] = 0; 215 vcpu->arch.cpuid_entries[i].padding[1] = 0; 216 vcpu->arch.cpuid_entries[i].padding[2] = 0; 217 } 218 vcpu->arch.cpuid_nent = cpuid->nent; 219 cpuid_fix_nx_cap(vcpu); 220 kvm_apic_set_version(vcpu); 221 kvm_x86_ops->cpuid_update(vcpu); 222 r = kvm_update_cpuid(vcpu); 223 224 out: 225 vfree(cpuid_entries); 226 return r; 227 } 228 229 int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu, 230 struct kvm_cpuid2 *cpuid, 231 struct kvm_cpuid_entry2 __user *entries) 232 { 233 int r; 234 235 r = -E2BIG; 236 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES) 237 goto out; 238 r = -EFAULT; 239 if (copy_from_user(&vcpu->arch.cpuid_entries, entries, 240 cpuid->nent * sizeof(struct kvm_cpuid_entry2))) 241 goto out; 242 vcpu->arch.cpuid_nent = cpuid->nent; 243 kvm_apic_set_version(vcpu); 244 kvm_x86_ops->cpuid_update(vcpu); 245 r = kvm_update_cpuid(vcpu); 246 out: 247 return r; 248 } 249 250 int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu, 251 struct kvm_cpuid2 *cpuid, 252 struct kvm_cpuid_entry2 __user *entries) 253 { 254 int r; 255 256 r = -E2BIG; 257 if (cpuid->nent < vcpu->arch.cpuid_nent) 258 goto out; 259 r = -EFAULT; 260 if (copy_to_user(entries, &vcpu->arch.cpuid_entries, 261 vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2))) 262 goto out; 263 return 0; 264 265 out: 266 cpuid->nent = vcpu->arch.cpuid_nent; 267 return r; 268 } 269 270 static void cpuid_mask(u32 *word, int wordnum) 271 { 272 *word &= boot_cpu_data.x86_capability[wordnum]; 273 } 274 275 static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function, 276 u32 index) 277 { 278 entry->function = function; 279 entry->index = index; 280 cpuid_count(entry->function, entry->index, 281 &entry->eax, &entry->ebx, &entry->ecx, &entry->edx); 282 entry->flags = 0; 283 } 284 285 static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry, 286 u32 func, u32 index, int *nent, int maxnent) 287 { 288 switch (func) { 289 case 0: 290 entry->eax = 1; /* only one leaf currently */ 291 ++*nent; 292 break; 293 case 1: 294 entry->ecx = F(MOVBE); 295 ++*nent; 296 break; 297 default: 298 break; 299 } 300 301 entry->function = func; 302 entry->index = index; 303 304 return 0; 305 } 306 307 static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, 308 u32 index, int *nent, int maxnent) 309 { 310 int r; 311 unsigned f_nx = is_efer_nx() ? F(NX) : 0; 312 #ifdef CONFIG_X86_64 313 unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL) 314 ? F(GBPAGES) : 0; 315 unsigned f_lm = F(LM); 316 #else 317 unsigned f_gbpages = 0; 318 unsigned f_lm = 0; 319 #endif 320 unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0; 321 unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0; 322 unsigned f_mpx = kvm_mpx_supported() ? F(MPX) : 0; 323 unsigned f_xsaves = kvm_x86_ops->xsaves_supported() ? F(XSAVES) : 0; 324 325 /* cpuid 1.edx */ 326 const u32 kvm_cpuid_1_edx_x86_features = 327 F(FPU) | F(VME) | F(DE) | F(PSE) | 328 F(TSC) | F(MSR) | F(PAE) | F(MCE) | 329 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SEP) | 330 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) | 331 F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLUSH) | 332 0 /* Reserved, DS, ACPI */ | F(MMX) | 333 F(FXSR) | F(XMM) | F(XMM2) | F(SELFSNOOP) | 334 0 /* HTT, TM, Reserved, PBE */; 335 /* cpuid 0x80000001.edx */ 336 const u32 kvm_cpuid_8000_0001_edx_x86_features = 337 F(FPU) | F(VME) | F(DE) | F(PSE) | 338 F(TSC) | F(MSR) | F(PAE) | F(MCE) | 339 F(CX8) | F(APIC) | 0 /* Reserved */ | F(SYSCALL) | 340 F(MTRR) | F(PGE) | F(MCA) | F(CMOV) | 341 F(PAT) | F(PSE36) | 0 /* Reserved */ | 342 f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) | 343 F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp | 344 0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW); 345 /* cpuid 1.ecx */ 346 const u32 kvm_cpuid_1_ecx_x86_features = 347 /* NOTE: MONITOR (and MWAIT) are emulated as NOP, 348 * but *not* advertised to guests via CPUID ! */ 349 F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ | 350 0 /* DS-CPL, VMX, SMX, EST */ | 351 0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ | 352 F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ | 353 F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) | 354 F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) | 355 0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) | 356 F(F16C) | F(RDRAND); 357 /* cpuid 0x80000001.ecx */ 358 const u32 kvm_cpuid_8000_0001_ecx_x86_features = 359 F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ | 360 F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) | 361 F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) | 362 0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM); 363 364 /* cpuid 0xC0000001.edx */ 365 const u32 kvm_cpuid_C000_0001_edx_x86_features = 366 F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) | 367 F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) | 368 F(PMM) | F(PMM_EN); 369 370 /* cpuid 7.0.ebx */ 371 const u32 kvm_cpuid_7_0_ebx_x86_features = 372 F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) | 373 F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) | 374 F(ADX) | F(SMAP) | F(AVX512IFMA) | F(AVX512F) | F(AVX512PF) | 375 F(AVX512ER) | F(AVX512CD) | F(CLFLUSHOPT) | F(CLWB) | F(AVX512DQ) | 376 F(SHA_NI) | F(AVX512BW) | F(AVX512VL); 377 378 /* cpuid 0xD.1.eax */ 379 const u32 kvm_cpuid_D_1_eax_x86_features = 380 F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | f_xsaves; 381 382 /* cpuid 7.0.ecx*/ 383 const u32 kvm_cpuid_7_0_ecx_x86_features = 384 F(AVX512VBMI) | F(PKU) | 0 /*OSPKE*/ | F(AVX512_VPOPCNTDQ); 385 386 /* cpuid 7.0.edx*/ 387 const u32 kvm_cpuid_7_0_edx_x86_features = 388 KF(AVX512_4VNNIW) | KF(AVX512_4FMAPS); 389 390 /* all calls to cpuid_count() should be made on the same cpu */ 391 get_cpu(); 392 393 r = -E2BIG; 394 395 if (*nent >= maxnent) 396 goto out; 397 398 do_cpuid_1_ent(entry, function, index); 399 ++*nent; 400 401 switch (function) { 402 case 0: 403 entry->eax = min(entry->eax, (u32)0xd); 404 break; 405 case 1: 406 entry->edx &= kvm_cpuid_1_edx_x86_features; 407 cpuid_mask(&entry->edx, CPUID_1_EDX); 408 entry->ecx &= kvm_cpuid_1_ecx_x86_features; 409 cpuid_mask(&entry->ecx, CPUID_1_ECX); 410 /* we support x2apic emulation even if host does not support 411 * it since we emulate x2apic in software */ 412 entry->ecx |= F(X2APIC); 413 break; 414 /* function 2 entries are STATEFUL. That is, repeated cpuid commands 415 * may return different values. This forces us to get_cpu() before 416 * issuing the first command, and also to emulate this annoying behavior 417 * in kvm_emulate_cpuid() using KVM_CPUID_FLAG_STATE_READ_NEXT */ 418 case 2: { 419 int t, times = entry->eax & 0xff; 420 421 entry->flags |= KVM_CPUID_FLAG_STATEFUL_FUNC; 422 entry->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT; 423 for (t = 1; t < times; ++t) { 424 if (*nent >= maxnent) 425 goto out; 426 427 do_cpuid_1_ent(&entry[t], function, 0); 428 entry[t].flags |= KVM_CPUID_FLAG_STATEFUL_FUNC; 429 ++*nent; 430 } 431 break; 432 } 433 /* function 4 has additional index. */ 434 case 4: { 435 int i, cache_type; 436 437 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; 438 /* read more entries until cache_type is zero */ 439 for (i = 1; ; ++i) { 440 if (*nent >= maxnent) 441 goto out; 442 443 cache_type = entry[i - 1].eax & 0x1f; 444 if (!cache_type) 445 break; 446 do_cpuid_1_ent(&entry[i], function, i); 447 entry[i].flags |= 448 KVM_CPUID_FLAG_SIGNIFCANT_INDEX; 449 ++*nent; 450 } 451 break; 452 } 453 case 6: /* Thermal management */ 454 entry->eax = 0x4; /* allow ARAT */ 455 entry->ebx = 0; 456 entry->ecx = 0; 457 entry->edx = 0; 458 break; 459 case 7: { 460 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; 461 /* Mask ebx against host capability word 9 */ 462 if (index == 0) { 463 entry->ebx &= kvm_cpuid_7_0_ebx_x86_features; 464 cpuid_mask(&entry->ebx, CPUID_7_0_EBX); 465 // TSC_ADJUST is emulated 466 entry->ebx |= F(TSC_ADJUST); 467 entry->ecx &= kvm_cpuid_7_0_ecx_x86_features; 468 cpuid_mask(&entry->ecx, CPUID_7_ECX); 469 /* PKU is not yet implemented for shadow paging. */ 470 if (!tdp_enabled) 471 entry->ecx &= ~F(PKU); 472 entry->edx &= kvm_cpuid_7_0_edx_x86_features; 473 entry->edx &= get_scattered_cpuid_leaf(7, 0, CPUID_EDX); 474 } else { 475 entry->ebx = 0; 476 entry->ecx = 0; 477 entry->edx = 0; 478 } 479 entry->eax = 0; 480 break; 481 } 482 case 9: 483 break; 484 case 0xa: { /* Architectural Performance Monitoring */ 485 struct x86_pmu_capability cap; 486 union cpuid10_eax eax; 487 union cpuid10_edx edx; 488 489 perf_get_x86_pmu_capability(&cap); 490 491 /* 492 * Only support guest architectural pmu on a host 493 * with architectural pmu. 494 */ 495 if (!cap.version) 496 memset(&cap, 0, sizeof(cap)); 497 498 eax.split.version_id = min(cap.version, 2); 499 eax.split.num_counters = cap.num_counters_gp; 500 eax.split.bit_width = cap.bit_width_gp; 501 eax.split.mask_length = cap.events_mask_len; 502 503 edx.split.num_counters_fixed = cap.num_counters_fixed; 504 edx.split.bit_width_fixed = cap.bit_width_fixed; 505 edx.split.reserved = 0; 506 507 entry->eax = eax.full; 508 entry->ebx = cap.events_mask; 509 entry->ecx = 0; 510 entry->edx = edx.full; 511 break; 512 } 513 /* function 0xb has additional index. */ 514 case 0xb: { 515 int i, level_type; 516 517 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; 518 /* read more entries until level_type is zero */ 519 for (i = 1; ; ++i) { 520 if (*nent >= maxnent) 521 goto out; 522 523 level_type = entry[i - 1].ecx & 0xff00; 524 if (!level_type) 525 break; 526 do_cpuid_1_ent(&entry[i], function, i); 527 entry[i].flags |= 528 KVM_CPUID_FLAG_SIGNIFCANT_INDEX; 529 ++*nent; 530 } 531 break; 532 } 533 case 0xd: { 534 int idx, i; 535 u64 supported = kvm_supported_xcr0(); 536 537 entry->eax &= supported; 538 entry->ebx = xstate_required_size(supported, false); 539 entry->ecx = entry->ebx; 540 entry->edx &= supported >> 32; 541 entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; 542 if (!supported) 543 break; 544 545 for (idx = 1, i = 1; idx < 64; ++idx) { 546 u64 mask = ((u64)1 << idx); 547 if (*nent >= maxnent) 548 goto out; 549 550 do_cpuid_1_ent(&entry[i], function, idx); 551 if (idx == 1) { 552 entry[i].eax &= kvm_cpuid_D_1_eax_x86_features; 553 cpuid_mask(&entry[i].eax, CPUID_D_1_EAX); 554 entry[i].ebx = 0; 555 if (entry[i].eax & (F(XSAVES)|F(XSAVEC))) 556 entry[i].ebx = 557 xstate_required_size(supported, 558 true); 559 } else { 560 if (entry[i].eax == 0 || !(supported & mask)) 561 continue; 562 if (WARN_ON_ONCE(entry[i].ecx & 1)) 563 continue; 564 } 565 entry[i].ecx = 0; 566 entry[i].edx = 0; 567 entry[i].flags |= 568 KVM_CPUID_FLAG_SIGNIFCANT_INDEX; 569 ++*nent; 570 ++i; 571 } 572 break; 573 } 574 case KVM_CPUID_SIGNATURE: { 575 static const char signature[12] = "KVMKVMKVM\0\0"; 576 const u32 *sigptr = (const u32 *)signature; 577 entry->eax = KVM_CPUID_FEATURES; 578 entry->ebx = sigptr[0]; 579 entry->ecx = sigptr[1]; 580 entry->edx = sigptr[2]; 581 break; 582 } 583 case KVM_CPUID_FEATURES: 584 entry->eax = (1 << KVM_FEATURE_CLOCKSOURCE) | 585 (1 << KVM_FEATURE_NOP_IO_DELAY) | 586 (1 << KVM_FEATURE_CLOCKSOURCE2) | 587 (1 << KVM_FEATURE_ASYNC_PF) | 588 (1 << KVM_FEATURE_PV_EOI) | 589 (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) | 590 (1 << KVM_FEATURE_PV_UNHALT); 591 592 if (sched_info_on()) 593 entry->eax |= (1 << KVM_FEATURE_STEAL_TIME); 594 595 entry->ebx = 0; 596 entry->ecx = 0; 597 entry->edx = 0; 598 break; 599 case 0x80000000: 600 entry->eax = min(entry->eax, 0x8000001a); 601 break; 602 case 0x80000001: 603 entry->edx &= kvm_cpuid_8000_0001_edx_x86_features; 604 cpuid_mask(&entry->edx, CPUID_8000_0001_EDX); 605 entry->ecx &= kvm_cpuid_8000_0001_ecx_x86_features; 606 cpuid_mask(&entry->ecx, CPUID_8000_0001_ECX); 607 break; 608 case 0x80000007: /* Advanced power management */ 609 /* invariant TSC is CPUID.80000007H:EDX[8] */ 610 entry->edx &= (1 << 8); 611 /* mask against host */ 612 entry->edx &= boot_cpu_data.x86_power; 613 entry->eax = entry->ebx = entry->ecx = 0; 614 break; 615 case 0x80000008: { 616 unsigned g_phys_as = (entry->eax >> 16) & 0xff; 617 unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U); 618 unsigned phys_as = entry->eax & 0xff; 619 620 if (!g_phys_as) 621 g_phys_as = phys_as; 622 entry->eax = g_phys_as | (virt_as << 8); 623 entry->ebx = entry->edx = 0; 624 break; 625 } 626 case 0x80000019: 627 entry->ecx = entry->edx = 0; 628 break; 629 case 0x8000001a: 630 break; 631 case 0x8000001d: 632 break; 633 /*Add support for Centaur's CPUID instruction*/ 634 case 0xC0000000: 635 /*Just support up to 0xC0000004 now*/ 636 entry->eax = min(entry->eax, 0xC0000004); 637 break; 638 case 0xC0000001: 639 entry->edx &= kvm_cpuid_C000_0001_edx_x86_features; 640 cpuid_mask(&entry->edx, CPUID_C000_0001_EDX); 641 break; 642 case 3: /* Processor serial number */ 643 case 5: /* MONITOR/MWAIT */ 644 case 0xC0000002: 645 case 0xC0000003: 646 case 0xC0000004: 647 default: 648 entry->eax = entry->ebx = entry->ecx = entry->edx = 0; 649 break; 650 } 651 652 kvm_x86_ops->set_supported_cpuid(function, entry); 653 654 r = 0; 655 656 out: 657 put_cpu(); 658 659 return r; 660 } 661 662 static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 func, 663 u32 idx, int *nent, int maxnent, unsigned int type) 664 { 665 if (type == KVM_GET_EMULATED_CPUID) 666 return __do_cpuid_ent_emulated(entry, func, idx, nent, maxnent); 667 668 return __do_cpuid_ent(entry, func, idx, nent, maxnent); 669 } 670 671 #undef F 672 673 struct kvm_cpuid_param { 674 u32 func; 675 u32 idx; 676 bool has_leaf_count; 677 bool (*qualifier)(const struct kvm_cpuid_param *param); 678 }; 679 680 static bool is_centaur_cpu(const struct kvm_cpuid_param *param) 681 { 682 return boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR; 683 } 684 685 static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries, 686 __u32 num_entries, unsigned int ioctl_type) 687 { 688 int i; 689 __u32 pad[3]; 690 691 if (ioctl_type != KVM_GET_EMULATED_CPUID) 692 return false; 693 694 /* 695 * We want to make sure that ->padding is being passed clean from 696 * userspace in case we want to use it for something in the future. 697 * 698 * Sadly, this wasn't enforced for KVM_GET_SUPPORTED_CPUID and so we 699 * have to give ourselves satisfied only with the emulated side. /me 700 * sheds a tear. 701 */ 702 for (i = 0; i < num_entries; i++) { 703 if (copy_from_user(pad, entries[i].padding, sizeof(pad))) 704 return true; 705 706 if (pad[0] || pad[1] || pad[2]) 707 return true; 708 } 709 return false; 710 } 711 712 int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid, 713 struct kvm_cpuid_entry2 __user *entries, 714 unsigned int type) 715 { 716 struct kvm_cpuid_entry2 *cpuid_entries; 717 int limit, nent = 0, r = -E2BIG, i; 718 u32 func; 719 static const struct kvm_cpuid_param param[] = { 720 { .func = 0, .has_leaf_count = true }, 721 { .func = 0x80000000, .has_leaf_count = true }, 722 { .func = 0xC0000000, .qualifier = is_centaur_cpu, .has_leaf_count = true }, 723 { .func = KVM_CPUID_SIGNATURE }, 724 { .func = KVM_CPUID_FEATURES }, 725 }; 726 727 if (cpuid->nent < 1) 728 goto out; 729 if (cpuid->nent > KVM_MAX_CPUID_ENTRIES) 730 cpuid->nent = KVM_MAX_CPUID_ENTRIES; 731 732 if (sanity_check_entries(entries, cpuid->nent, type)) 733 return -EINVAL; 734 735 r = -ENOMEM; 736 cpuid_entries = vzalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent); 737 if (!cpuid_entries) 738 goto out; 739 740 r = 0; 741 for (i = 0; i < ARRAY_SIZE(param); i++) { 742 const struct kvm_cpuid_param *ent = ¶m[i]; 743 744 if (ent->qualifier && !ent->qualifier(ent)) 745 continue; 746 747 r = do_cpuid_ent(&cpuid_entries[nent], ent->func, ent->idx, 748 &nent, cpuid->nent, type); 749 750 if (r) 751 goto out_free; 752 753 if (!ent->has_leaf_count) 754 continue; 755 756 limit = cpuid_entries[nent - 1].eax; 757 for (func = ent->func + 1; func <= limit && nent < cpuid->nent && r == 0; ++func) 758 r = do_cpuid_ent(&cpuid_entries[nent], func, ent->idx, 759 &nent, cpuid->nent, type); 760 761 if (r) 762 goto out_free; 763 } 764 765 r = -EFAULT; 766 if (copy_to_user(entries, cpuid_entries, 767 nent * sizeof(struct kvm_cpuid_entry2))) 768 goto out_free; 769 cpuid->nent = nent; 770 r = 0; 771 772 out_free: 773 vfree(cpuid_entries); 774 out: 775 return r; 776 } 777 778 static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i) 779 { 780 struct kvm_cpuid_entry2 *e = &vcpu->arch.cpuid_entries[i]; 781 int j, nent = vcpu->arch.cpuid_nent; 782 783 e->flags &= ~KVM_CPUID_FLAG_STATE_READ_NEXT; 784 /* when no next entry is found, the current entry[i] is reselected */ 785 for (j = i + 1; ; j = (j + 1) % nent) { 786 struct kvm_cpuid_entry2 *ej = &vcpu->arch.cpuid_entries[j]; 787 if (ej->function == e->function) { 788 ej->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT; 789 return j; 790 } 791 } 792 return 0; /* silence gcc, even though control never reaches here */ 793 } 794 795 /* find an entry with matching function, matching index (if needed), and that 796 * should be read next (if it's stateful) */ 797 static int is_matching_cpuid_entry(struct kvm_cpuid_entry2 *e, 798 u32 function, u32 index) 799 { 800 if (e->function != function) 801 return 0; 802 if ((e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) && e->index != index) 803 return 0; 804 if ((e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) && 805 !(e->flags & KVM_CPUID_FLAG_STATE_READ_NEXT)) 806 return 0; 807 return 1; 808 } 809 810 struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu, 811 u32 function, u32 index) 812 { 813 int i; 814 struct kvm_cpuid_entry2 *best = NULL; 815 816 for (i = 0; i < vcpu->arch.cpuid_nent; ++i) { 817 struct kvm_cpuid_entry2 *e; 818 819 e = &vcpu->arch.cpuid_entries[i]; 820 if (is_matching_cpuid_entry(e, function, index)) { 821 if (e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) 822 move_to_next_stateful_cpuid_entry(vcpu, i); 823 best = e; 824 break; 825 } 826 } 827 return best; 828 } 829 EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry); 830 831 /* 832 * If no match is found, check whether we exceed the vCPU's limit 833 * and return the content of the highest valid _standard_ leaf instead. 834 * This is to satisfy the CPUID specification. 835 */ 836 static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu, 837 u32 function, u32 index) 838 { 839 struct kvm_cpuid_entry2 *maxlevel; 840 841 maxlevel = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0); 842 if (!maxlevel || maxlevel->eax >= function) 843 return NULL; 844 if (function & 0x80000000) { 845 maxlevel = kvm_find_cpuid_entry(vcpu, 0, 0); 846 if (!maxlevel) 847 return NULL; 848 } 849 return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index); 850 } 851 852 void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx) 853 { 854 u32 function = *eax, index = *ecx; 855 struct kvm_cpuid_entry2 *best; 856 857 best = kvm_find_cpuid_entry(vcpu, function, index); 858 859 if (!best) 860 best = check_cpuid_limit(vcpu, function, index); 861 862 if (best) { 863 *eax = best->eax; 864 *ebx = best->ebx; 865 *ecx = best->ecx; 866 *edx = best->edx; 867 } else 868 *eax = *ebx = *ecx = *edx = 0; 869 trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx); 870 } 871 EXPORT_SYMBOL_GPL(kvm_cpuid); 872 873 int kvm_emulate_cpuid(struct kvm_vcpu *vcpu) 874 { 875 u32 eax, ebx, ecx, edx; 876 877 eax = kvm_register_read(vcpu, VCPU_REGS_RAX); 878 ecx = kvm_register_read(vcpu, VCPU_REGS_RCX); 879 kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx); 880 kvm_register_write(vcpu, VCPU_REGS_RAX, eax); 881 kvm_register_write(vcpu, VCPU_REGS_RBX, ebx); 882 kvm_register_write(vcpu, VCPU_REGS_RCX, ecx); 883 kvm_register_write(vcpu, VCPU_REGS_RDX, edx); 884 return kvm_skip_emulated_instruction(vcpu); 885 } 886 EXPORT_SYMBOL_GPL(kvm_emulate_cpuid); 887