// SPDX-License-Identifier: GPL-2.0-only /* * Kernel-based Virtual Machine driver for Linux * cpuid support routines * * derived from arch/x86/kvm/x86.c * * Copyright 2011 Red Hat, Inc. and/or its affiliates. * Copyright IBM Corporation, 2008 */ #include #include #include #include #include #include #include #include #include "cpuid.h" #include "lapic.h" #include "mmu.h" #include "trace.h" #include "pmu.h" static u32 xstate_required_size(u64 xstate_bv, bool compacted) { int feature_bit = 0; u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET; xstate_bv &= XFEATURE_MASK_EXTEND; while (xstate_bv) { if (xstate_bv & 0x1) { u32 eax, ebx, ecx, edx, offset; cpuid_count(0xD, feature_bit, &eax, &ebx, &ecx, &edx); offset = compacted ? ret : ebx; ret = max(ret, offset + eax); } xstate_bv >>= 1; feature_bit++; } return ret; } bool kvm_mpx_supported(void) { return ((host_xcr0 & (XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR)) && kvm_x86_ops->mpx_supported()); } EXPORT_SYMBOL_GPL(kvm_mpx_supported); u64 kvm_supported_xcr0(void) { u64 xcr0 = KVM_SUPPORTED_XCR0 & host_xcr0; if (!kvm_mpx_supported()) xcr0 &= ~(XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR); return xcr0; } #define F feature_bit int kvm_update_cpuid(struct kvm_vcpu *vcpu) { struct kvm_cpuid_entry2 *best; struct kvm_lapic *apic = vcpu->arch.apic; best = kvm_find_cpuid_entry(vcpu, 1, 0); if (!best) return 0; /* Update OSXSAVE bit */ if (boot_cpu_has(X86_FEATURE_XSAVE) && best->function == 0x1) { best->ecx &= ~F(OSXSAVE); if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE)) best->ecx |= F(OSXSAVE); } best->edx &= ~F(APIC); if (vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE) best->edx |= F(APIC); if (apic) { if (best->ecx & F(TSC_DEADLINE_TIMER)) apic->lapic_timer.timer_mode_mask = 3 << 17; else apic->lapic_timer.timer_mode_mask = 1 << 17; } best = kvm_find_cpuid_entry(vcpu, 7, 0); if (best) { /* Update OSPKE bit */ if (boot_cpu_has(X86_FEATURE_PKU) && best->function == 0x7) { best->ecx &= ~F(OSPKE); if (kvm_read_cr4_bits(vcpu, X86_CR4_PKE)) best->ecx |= F(OSPKE); } } best = kvm_find_cpuid_entry(vcpu, 0xD, 0); if (!best) { vcpu->arch.guest_supported_xcr0 = 0; vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET; } else { vcpu->arch.guest_supported_xcr0 = (best->eax | ((u64)best->edx << 32)) & kvm_supported_xcr0(); vcpu->arch.guest_xstate_size = best->ebx = xstate_required_size(vcpu->arch.xcr0, false); } best = kvm_find_cpuid_entry(vcpu, 0xD, 1); if (best && (best->eax & (F(XSAVES) | F(XSAVEC)))) best->ebx = xstate_required_size(vcpu->arch.xcr0, true); /* * The existing code assumes virtual address is 48-bit or 57-bit in the * canonical address checks; exit if it is ever changed. */ best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0); if (best) { int vaddr_bits = (best->eax & 0xff00) >> 8; if (vaddr_bits != 48 && vaddr_bits != 57 && vaddr_bits != 0) return -EINVAL; } best = kvm_find_cpuid_entry(vcpu, KVM_CPUID_FEATURES, 0); if (kvm_hlt_in_guest(vcpu->kvm) && best && (best->eax & (1 << KVM_FEATURE_PV_UNHALT))) best->eax &= ~(1 << KVM_FEATURE_PV_UNHALT); if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT)) { best = kvm_find_cpuid_entry(vcpu, 0x1, 0); if (best) { if (vcpu->arch.ia32_misc_enable_msr & MSR_IA32_MISC_ENABLE_MWAIT) best->ecx |= F(MWAIT); else best->ecx &= ~F(MWAIT); } } /* Update physical-address width */ vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu); kvm_mmu_reset_context(vcpu); kvm_pmu_refresh(vcpu); return 0; } static int is_efer_nx(void) { unsigned long long efer = 0; rdmsrl_safe(MSR_EFER, &efer); return efer & EFER_NX; } static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu) { int i; struct kvm_cpuid_entry2 *e, *entry; entry = NULL; for (i = 0; i < vcpu->arch.cpuid_nent; ++i) { e = &vcpu->arch.cpuid_entries[i]; if (e->function == 0x80000001) { entry = e; break; } } if (entry && (entry->edx & F(NX)) && !is_efer_nx()) { entry->edx &= ~F(NX); printk(KERN_INFO "kvm: guest NX capability removed\n"); } } int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu) { struct kvm_cpuid_entry2 *best; best = kvm_find_cpuid_entry(vcpu, 0x80000000, 0); if (!best || best->eax < 0x80000008) goto not_found; best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0); if (best) return best->eax & 0xff; not_found: return 36; } EXPORT_SYMBOL_GPL(cpuid_query_maxphyaddr); /* when an old userspace process fills a new kernel module */ int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid *cpuid, struct kvm_cpuid_entry __user *entries) { int r, i; struct kvm_cpuid_entry *cpuid_entries = NULL; r = -E2BIG; if (cpuid->nent > KVM_MAX_CPUID_ENTRIES) goto out; r = -ENOMEM; if (cpuid->nent) { cpuid_entries = vmalloc(array_size(sizeof(struct kvm_cpuid_entry), cpuid->nent)); if (!cpuid_entries) goto out; r = -EFAULT; if (copy_from_user(cpuid_entries, entries, cpuid->nent * sizeof(struct kvm_cpuid_entry))) goto out; } for (i = 0; i < cpuid->nent; i++) { vcpu->arch.cpuid_entries[i].function = cpuid_entries[i].function; vcpu->arch.cpuid_entries[i].eax = cpuid_entries[i].eax; vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx; vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx; vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx; vcpu->arch.cpuid_entries[i].index = 0; vcpu->arch.cpuid_entries[i].flags = 0; vcpu->arch.cpuid_entries[i].padding[0] = 0; vcpu->arch.cpuid_entries[i].padding[1] = 0; vcpu->arch.cpuid_entries[i].padding[2] = 0; } vcpu->arch.cpuid_nent = cpuid->nent; cpuid_fix_nx_cap(vcpu); kvm_apic_set_version(vcpu); kvm_x86_ops->cpuid_update(vcpu); r = kvm_update_cpuid(vcpu); out: vfree(cpuid_entries); return r; } int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid, struct kvm_cpuid_entry2 __user *entries) { int r; r = -E2BIG; if (cpuid->nent > KVM_MAX_CPUID_ENTRIES) goto out; r = -EFAULT; if (copy_from_user(&vcpu->arch.cpuid_entries, entries, cpuid->nent * sizeof(struct kvm_cpuid_entry2))) goto out; vcpu->arch.cpuid_nent = cpuid->nent; kvm_apic_set_version(vcpu); kvm_x86_ops->cpuid_update(vcpu); r = kvm_update_cpuid(vcpu); out: return r; } int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid, struct kvm_cpuid_entry2 __user *entries) { int r; r = -E2BIG; if (cpuid->nent < vcpu->arch.cpuid_nent) goto out; r = -EFAULT; if (copy_to_user(entries, &vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2))) goto out; return 0; out: cpuid->nent = vcpu->arch.cpuid_nent; return r; } static __always_inline void cpuid_mask(u32 *word, int wordnum) { reverse_cpuid_check(wordnum); *word &= boot_cpu_data.x86_capability[wordnum]; } static struct kvm_cpuid_entry2 *do_host_cpuid(struct kvm_cpuid_entry2 *entry, int *nent, int maxnent, u32 function, u32 index) { if (*nent >= maxnent) return NULL; ++*nent; entry->function = function; entry->index = index; entry->flags = 0; cpuid_count(entry->function, entry->index, &entry->eax, &entry->ebx, &entry->ecx, &entry->edx); switch (function) { case 2: entry->flags |= KVM_CPUID_FLAG_STATEFUL_FUNC; break; case 4: case 7: case 0xb: case 0xd: case 0xf: case 0x10: case 0x12: case 0x14: case 0x17: case 0x18: case 0x1f: case 0x8000001d: entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; break; } return entry; } static int __do_cpuid_func_emulated(struct kvm_cpuid_entry2 *entry, u32 func, int *nent, int maxnent) { entry->function = func; entry->index = 0; entry->flags = 0; switch (func) { case 0: entry->eax = 7; ++*nent; break; case 1: entry->ecx = F(MOVBE); ++*nent; break; case 7: entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; entry->eax = 0; entry->ecx = F(RDPID); ++*nent; default: break; } return 0; } static inline void do_cpuid_7_mask(struct kvm_cpuid_entry2 *entry) { unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0; unsigned f_mpx = kvm_mpx_supported() ? F(MPX) : 0; unsigned f_umip = kvm_x86_ops->umip_emulated() ? F(UMIP) : 0; unsigned f_intel_pt = kvm_x86_ops->pt_supported() ? F(INTEL_PT) : 0; unsigned f_la57; unsigned f_pku = kvm_x86_ops->pku_supported() ? F(PKU) : 0; /* cpuid 7.0.ebx */ const u32 kvm_cpuid_7_0_ebx_x86_features = F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) | F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) | F(ADX) | F(SMAP) | F(AVX512IFMA) | F(AVX512F) | F(AVX512PF) | F(AVX512ER) | F(AVX512CD) | F(CLFLUSHOPT) | F(CLWB) | F(AVX512DQ) | F(SHA_NI) | F(AVX512BW) | F(AVX512VL) | f_intel_pt; /* cpuid 7.0.ecx*/ const u32 kvm_cpuid_7_0_ecx_x86_features = F(AVX512VBMI) | F(LA57) | 0 /*PKU*/ | 0 /*OSPKE*/ | F(RDPID) | F(AVX512_VPOPCNTDQ) | F(UMIP) | F(AVX512_VBMI2) | F(GFNI) | F(VAES) | F(VPCLMULQDQ) | F(AVX512_VNNI) | F(AVX512_BITALG) | F(CLDEMOTE) | F(MOVDIRI) | F(MOVDIR64B) | 0 /*WAITPKG*/; /* cpuid 7.0.edx*/ const u32 kvm_cpuid_7_0_edx_x86_features = F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) | F(SPEC_CTRL_SSBD) | F(ARCH_CAPABILITIES) | F(INTEL_STIBP) | F(MD_CLEAR); /* cpuid 7.1.eax */ const u32 kvm_cpuid_7_1_eax_x86_features = F(AVX512_BF16); switch (entry->index) { case 0: entry->eax = min(entry->eax, 1u); entry->ebx &= kvm_cpuid_7_0_ebx_x86_features; cpuid_mask(&entry->ebx, CPUID_7_0_EBX); /* TSC_ADJUST is emulated */ entry->ebx |= F(TSC_ADJUST); entry->ecx &= kvm_cpuid_7_0_ecx_x86_features; f_la57 = entry->ecx & F(LA57); cpuid_mask(&entry->ecx, CPUID_7_ECX); /* Set LA57 based on hardware capability. */ entry->ecx |= f_la57; entry->ecx |= f_umip; entry->ecx |= f_pku; /* PKU is not yet implemented for shadow paging. */ if (!tdp_enabled || !boot_cpu_has(X86_FEATURE_OSPKE)) entry->ecx &= ~F(PKU); entry->edx &= kvm_cpuid_7_0_edx_x86_features; cpuid_mask(&entry->edx, CPUID_7_EDX); if (boot_cpu_has(X86_FEATURE_IBPB) && boot_cpu_has(X86_FEATURE_IBRS)) entry->edx |= F(SPEC_CTRL); if (boot_cpu_has(X86_FEATURE_STIBP)) entry->edx |= F(INTEL_STIBP); if (boot_cpu_has(X86_FEATURE_AMD_SSBD)) entry->edx |= F(SPEC_CTRL_SSBD); /* * We emulate ARCH_CAPABILITIES in software even * if the host doesn't support it. */ entry->edx |= F(ARCH_CAPABILITIES); break; case 1: entry->eax &= kvm_cpuid_7_1_eax_x86_features; entry->ebx = 0; entry->ecx = 0; entry->edx = 0; break; default: WARN_ON_ONCE(1); entry->eax = 0; entry->ebx = 0; entry->ecx = 0; entry->edx = 0; break; } } static inline int __do_cpuid_func(struct kvm_cpuid_entry2 *entry, u32 function, int *nent, int maxnent) { int r, i, max_idx; unsigned f_nx = is_efer_nx() ? F(NX) : 0; #ifdef CONFIG_X86_64 unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL) ? F(GBPAGES) : 0; unsigned f_lm = F(LM); #else unsigned f_gbpages = 0; unsigned f_lm = 0; #endif unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0; unsigned f_xsaves = kvm_x86_ops->xsaves_supported() ? F(XSAVES) : 0; unsigned f_intel_pt = kvm_x86_ops->pt_supported() ? F(INTEL_PT) : 0; /* cpuid 1.edx */ const u32 kvm_cpuid_1_edx_x86_features = F(FPU) | F(VME) | F(DE) | F(PSE) | F(TSC) | F(MSR) | F(PAE) | F(MCE) | F(CX8) | F(APIC) | 0 /* Reserved */ | F(SEP) | F(MTRR) | F(PGE) | F(MCA) | F(CMOV) | F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLUSH) | 0 /* Reserved, DS, ACPI */ | F(MMX) | F(FXSR) | F(XMM) | F(XMM2) | F(SELFSNOOP) | 0 /* HTT, TM, Reserved, PBE */; /* cpuid 0x80000001.edx */ const u32 kvm_cpuid_8000_0001_edx_x86_features = F(FPU) | F(VME) | F(DE) | F(PSE) | F(TSC) | F(MSR) | F(PAE) | F(MCE) | F(CX8) | F(APIC) | 0 /* Reserved */ | F(SYSCALL) | F(MTRR) | F(PGE) | F(MCA) | F(CMOV) | F(PAT) | F(PSE36) | 0 /* Reserved */ | f_nx | 0 /* Reserved */ | F(MMXEXT) | F(MMX) | F(FXSR) | F(FXSR_OPT) | f_gbpages | f_rdtscp | 0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW); /* cpuid 1.ecx */ const u32 kvm_cpuid_1_ecx_x86_features = /* NOTE: MONITOR (and MWAIT) are emulated as NOP, * but *not* advertised to guests via CPUID ! */ F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ | 0 /* DS-CPL, VMX, SMX, EST */ | 0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ | F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ | F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) | F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) | 0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) | F(F16C) | F(RDRAND); /* cpuid 0x80000001.ecx */ const u32 kvm_cpuid_8000_0001_ecx_x86_features = F(LAHF_LM) | F(CMP_LEGACY) | 0 /*SVM*/ | 0 /* ExtApicSpace */ | F(CR8_LEGACY) | F(ABM) | F(SSE4A) | F(MISALIGNSSE) | F(3DNOWPREFETCH) | F(OSVW) | 0 /* IBS */ | F(XOP) | 0 /* SKINIT, WDT, LWP */ | F(FMA4) | F(TBM) | F(TOPOEXT) | F(PERFCTR_CORE); /* cpuid 0x80000008.ebx */ const u32 kvm_cpuid_8000_0008_ebx_x86_features = F(CLZERO) | F(XSAVEERPTR) | F(WBNOINVD) | F(AMD_IBPB) | F(AMD_IBRS) | F(AMD_SSBD) | F(VIRT_SSBD) | F(AMD_SSB_NO) | F(AMD_STIBP) | F(AMD_STIBP_ALWAYS_ON); /* cpuid 0xC0000001.edx */ const u32 kvm_cpuid_C000_0001_edx_x86_features = F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) | F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) | F(PMM) | F(PMM_EN); /* cpuid 0xD.1.eax */ const u32 kvm_cpuid_D_1_eax_x86_features = F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | f_xsaves; /* all calls to cpuid_count() should be made on the same cpu */ get_cpu(); r = -E2BIG; if (WARN_ON(!do_host_cpuid(entry, nent, maxnent, function, 0))) goto out; switch (function) { case 0: /* Limited to the highest leaf implemented in KVM. */ entry->eax = min(entry->eax, 0x1fU); break; case 1: entry->edx &= kvm_cpuid_1_edx_x86_features; cpuid_mask(&entry->edx, CPUID_1_EDX); entry->ecx &= kvm_cpuid_1_ecx_x86_features; cpuid_mask(&entry->ecx, CPUID_1_ECX); /* we support x2apic emulation even if host does not support * it since we emulate x2apic in software */ entry->ecx |= F(X2APIC); break; /* function 2 entries are STATEFUL. That is, repeated cpuid commands * may return different values. This forces us to get_cpu() before * issuing the first command, and also to emulate this annoying behavior * in kvm_emulate_cpuid() using KVM_CPUID_FLAG_STATE_READ_NEXT */ case 2: entry->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT; for (i = 1, max_idx = entry->eax & 0xff; i < max_idx; ++i) { if (!do_host_cpuid(&entry[i], nent, maxnent, function, 0)) goto out; } break; /* functions 4 and 0x8000001d have additional index. */ case 4: case 0x8000001d: /* * Read entries until the cache type in the previous entry is * zero, i.e. indicates an invalid entry. */ for (i = 1; entry[i - 1].eax & 0x1f; ++i) { if (!do_host_cpuid(&entry[i], nent, maxnent, function, i)) goto out; } break; case 6: /* Thermal management */ entry->eax = 0x4; /* allow ARAT */ entry->ebx = 0; entry->ecx = 0; entry->edx = 0; break; /* function 7 has additional index. */ case 7: do_cpuid_7_mask(entry); for (i = 1, max_idx = entry->eax; i <= max_idx; i++) { if (!do_host_cpuid(&entry[i], nent, maxnent, function, i)) goto out; do_cpuid_7_mask(&entry[i]); } break; case 9: break; case 0xa: { /* Architectural Performance Monitoring */ struct x86_pmu_capability cap; union cpuid10_eax eax; union cpuid10_edx edx; perf_get_x86_pmu_capability(&cap); /* * Only support guest architectural pmu on a host * with architectural pmu. */ if (!cap.version) memset(&cap, 0, sizeof(cap)); eax.split.version_id = min(cap.version, 2); eax.split.num_counters = cap.num_counters_gp; eax.split.bit_width = cap.bit_width_gp; eax.split.mask_length = cap.events_mask_len; edx.split.num_counters_fixed = cap.num_counters_fixed; edx.split.bit_width_fixed = cap.bit_width_fixed; edx.split.reserved = 0; entry->eax = eax.full; entry->ebx = cap.events_mask; entry->ecx = 0; entry->edx = edx.full; break; } /* * Per Intel's SDM, the 0x1f is a superset of 0xb, * thus they can be handled by common code. */ case 0x1f: case 0xb: /* * We filled in entry[0] for CPUID(EAX=, * ECX=00H) above. If its level type (ECX[15:8]) is * zero, then the leaf is unimplemented, and we're * done. Otherwise, continue to populate entries * until the level type (ECX[15:8]) of the previously * added entry is zero. */ for (i = 1; entry[i - 1].ecx & 0xff00; ++i) { if (!do_host_cpuid(&entry[i], nent, maxnent, function, i)) goto out; } break; case 0xd: { int idx; u64 supported = kvm_supported_xcr0(); entry->eax &= supported; entry->ebx = xstate_required_size(supported, false); entry->ecx = entry->ebx; entry->edx &= supported >> 32; if (!supported) break; if (!do_host_cpuid(&entry[1], nent, maxnent, function, 1)) goto out; entry[1].eax &= kvm_cpuid_D_1_eax_x86_features; cpuid_mask(&entry[1].eax, CPUID_D_1_EAX); if (entry[1].eax & (F(XSAVES)|F(XSAVEC))) entry[1].ebx = xstate_required_size(supported, true); else entry[1].ebx = 0; /* Saving XSS controlled state via XSAVES isn't supported. */ entry[1].ecx = 0; entry[1].edx = 0; for (idx = 2, i = 2; idx < 64; ++idx) { if (!(supported & BIT_ULL(idx))) continue; if (!do_host_cpuid(&entry[i], nent, maxnent, function, idx)) goto out; /* * The @supported check above should have filtered out * invalid sub-leafs as well as sub-leafs managed by * IA32_XSS MSR. Only XCR0-managed sub-leafs should * reach this point, and they should have a non-zero * save state size. */ if (WARN_ON_ONCE(!entry[i].eax || (entry[i].ecx & 1))) { --*nent; continue; } entry[i].ecx = 0; entry[i].edx = 0; ++i; } break; } /* Intel PT */ case 0x14: if (!f_intel_pt) break; for (i = 1, max_idx = entry->eax; i <= max_idx; ++i) { if (!do_host_cpuid(&entry[i], nent, maxnent, function, i)) goto out; } break; case KVM_CPUID_SIGNATURE: { static const char signature[12] = "KVMKVMKVM\0\0"; const u32 *sigptr = (const u32 *)signature; entry->eax = KVM_CPUID_FEATURES; entry->ebx = sigptr[0]; entry->ecx = sigptr[1]; entry->edx = sigptr[2]; break; } case KVM_CPUID_FEATURES: entry->eax = (1 << KVM_FEATURE_CLOCKSOURCE) | (1 << KVM_FEATURE_NOP_IO_DELAY) | (1 << KVM_FEATURE_CLOCKSOURCE2) | (1 << KVM_FEATURE_ASYNC_PF) | (1 << KVM_FEATURE_PV_EOI) | (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) | (1 << KVM_FEATURE_PV_UNHALT) | (1 << KVM_FEATURE_PV_TLB_FLUSH) | (1 << KVM_FEATURE_ASYNC_PF_VMEXIT) | (1 << KVM_FEATURE_PV_SEND_IPI) | (1 << KVM_FEATURE_POLL_CONTROL) | (1 << KVM_FEATURE_PV_SCHED_YIELD); if (sched_info_on()) entry->eax |= (1 << KVM_FEATURE_STEAL_TIME); entry->ebx = 0; entry->ecx = 0; entry->edx = 0; break; case 0x80000000: entry->eax = min(entry->eax, 0x8000001f); break; case 0x80000001: entry->edx &= kvm_cpuid_8000_0001_edx_x86_features; cpuid_mask(&entry->edx, CPUID_8000_0001_EDX); entry->ecx &= kvm_cpuid_8000_0001_ecx_x86_features; cpuid_mask(&entry->ecx, CPUID_8000_0001_ECX); break; case 0x80000007: /* Advanced power management */ /* invariant TSC is CPUID.80000007H:EDX[8] */ entry->edx &= (1 << 8); /* mask against host */ entry->edx &= boot_cpu_data.x86_power; entry->eax = entry->ebx = entry->ecx = 0; break; case 0x80000008: { unsigned g_phys_as = (entry->eax >> 16) & 0xff; unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U); unsigned phys_as = entry->eax & 0xff; if (!g_phys_as) g_phys_as = phys_as; entry->eax = g_phys_as | (virt_as << 8); entry->edx = 0; entry->ebx &= kvm_cpuid_8000_0008_ebx_x86_features; cpuid_mask(&entry->ebx, CPUID_8000_0008_EBX); /* * AMD has separate bits for each SPEC_CTRL bit. * arch/x86/kernel/cpu/bugs.c is kind enough to * record that in cpufeatures so use them. */ if (boot_cpu_has(X86_FEATURE_IBPB)) entry->ebx |= F(AMD_IBPB); if (boot_cpu_has(X86_FEATURE_IBRS)) entry->ebx |= F(AMD_IBRS); if (boot_cpu_has(X86_FEATURE_STIBP)) entry->ebx |= F(AMD_STIBP); if (boot_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD)) entry->ebx |= F(AMD_SSBD); if (!boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS)) entry->ebx |= F(AMD_SSB_NO); /* * The preference is to use SPEC CTRL MSR instead of the * VIRT_SPEC MSR. */ if (boot_cpu_has(X86_FEATURE_LS_CFG_SSBD) && !boot_cpu_has(X86_FEATURE_AMD_SSBD)) entry->ebx |= F(VIRT_SSBD); break; } case 0x80000019: entry->ecx = entry->edx = 0; break; case 0x8000001a: case 0x8000001e: break; /* Support memory encryption cpuid if host supports it */ case 0x8000001F: if (!boot_cpu_has(X86_FEATURE_SEV)) entry->eax = entry->ebx = entry->ecx = entry->edx = 0; break; /*Add support for Centaur's CPUID instruction*/ case 0xC0000000: /*Just support up to 0xC0000004 now*/ entry->eax = min(entry->eax, 0xC0000004); break; case 0xC0000001: entry->edx &= kvm_cpuid_C000_0001_edx_x86_features; cpuid_mask(&entry->edx, CPUID_C000_0001_EDX); break; case 3: /* Processor serial number */ case 5: /* MONITOR/MWAIT */ case 0xC0000002: case 0xC0000003: case 0xC0000004: default: entry->eax = entry->ebx = entry->ecx = entry->edx = 0; break; } kvm_x86_ops->set_supported_cpuid(function, entry); r = 0; out: put_cpu(); return r; } static int do_cpuid_func(struct kvm_cpuid_entry2 *entry, u32 func, int *nent, int maxnent, unsigned int type) { if (*nent >= maxnent) return -E2BIG; if (type == KVM_GET_EMULATED_CPUID) return __do_cpuid_func_emulated(entry, func, nent, maxnent); return __do_cpuid_func(entry, func, nent, maxnent); } #define CENTAUR_CPUID_SIGNATURE 0xC0000000 static int get_cpuid_func(struct kvm_cpuid_entry2 *entries, u32 func, int *nent, int maxnent, unsigned int type) { u32 limit; int r; if (func == CENTAUR_CPUID_SIGNATURE && boot_cpu_data.x86_vendor != X86_VENDOR_CENTAUR) return 0; r = do_cpuid_func(&entries[*nent], func, nent, maxnent, type); if (r) return r; limit = entries[*nent - 1].eax; for (func = func + 1; func <= limit; ++func) { if (*nent >= maxnent) return -E2BIG; r = do_cpuid_func(&entries[*nent], func, nent, maxnent, type); if (r) break; } return r; } static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries, __u32 num_entries, unsigned int ioctl_type) { int i; __u32 pad[3]; if (ioctl_type != KVM_GET_EMULATED_CPUID) return false; /* * We want to make sure that ->padding is being passed clean from * userspace in case we want to use it for something in the future. * * Sadly, this wasn't enforced for KVM_GET_SUPPORTED_CPUID and so we * have to give ourselves satisfied only with the emulated side. /me * sheds a tear. */ for (i = 0; i < num_entries; i++) { if (copy_from_user(pad, entries[i].padding, sizeof(pad))) return true; if (pad[0] || pad[1] || pad[2]) return true; } return false; } int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid, struct kvm_cpuid_entry2 __user *entries, unsigned int type) { static const u32 funcs[] = { 0, 0x80000000, CENTAUR_CPUID_SIGNATURE, KVM_CPUID_SIGNATURE, }; struct kvm_cpuid_entry2 *cpuid_entries; int nent = 0, r, i; if (cpuid->nent < 1) return -E2BIG; if (cpuid->nent > KVM_MAX_CPUID_ENTRIES) cpuid->nent = KVM_MAX_CPUID_ENTRIES; if (sanity_check_entries(entries, cpuid->nent, type)) return -EINVAL; cpuid_entries = vzalloc(array_size(sizeof(struct kvm_cpuid_entry2), cpuid->nent)); if (!cpuid_entries) return -ENOMEM; for (i = 0; i < ARRAY_SIZE(funcs); i++) { r = get_cpuid_func(cpuid_entries, funcs[i], &nent, cpuid->nent, type); if (r) goto out_free; } cpuid->nent = nent; if (copy_to_user(entries, cpuid_entries, nent * sizeof(struct kvm_cpuid_entry2))) r = -EFAULT; out_free: vfree(cpuid_entries); return r; } static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i) { struct kvm_cpuid_entry2 *e = &vcpu->arch.cpuid_entries[i]; struct kvm_cpuid_entry2 *ej; int j = i; int nent = vcpu->arch.cpuid_nent; e->flags &= ~KVM_CPUID_FLAG_STATE_READ_NEXT; /* when no next entry is found, the current entry[i] is reselected */ do { j = (j + 1) % nent; ej = &vcpu->arch.cpuid_entries[j]; } while (ej->function != e->function); ej->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT; return j; } /* find an entry with matching function, matching index (if needed), and that * should be read next (if it's stateful) */ static int is_matching_cpuid_entry(struct kvm_cpuid_entry2 *e, u32 function, u32 index) { if (e->function != function) return 0; if ((e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) && e->index != index) return 0; if ((e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) && !(e->flags & KVM_CPUID_FLAG_STATE_READ_NEXT)) return 0; return 1; } struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu, u32 function, u32 index) { int i; struct kvm_cpuid_entry2 *best = NULL; for (i = 0; i < vcpu->arch.cpuid_nent; ++i) { struct kvm_cpuid_entry2 *e; e = &vcpu->arch.cpuid_entries[i]; if (is_matching_cpuid_entry(e, function, index)) { if (e->flags & KVM_CPUID_FLAG_STATEFUL_FUNC) move_to_next_stateful_cpuid_entry(vcpu, i); best = e; break; } } return best; } EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry); /* * If the basic or extended CPUID leaf requested is higher than the * maximum supported basic or extended leaf, respectively, then it is * out of range. */ static bool cpuid_function_in_range(struct kvm_vcpu *vcpu, u32 function) { struct kvm_cpuid_entry2 *max; max = kvm_find_cpuid_entry(vcpu, function & 0x80000000, 0); return max && function <= max->eax; } bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, bool check_limit) { u32 function = *eax, index = *ecx; struct kvm_cpuid_entry2 *entry; struct kvm_cpuid_entry2 *max; bool found; entry = kvm_find_cpuid_entry(vcpu, function, index); found = entry; /* * Intel CPUID semantics treats any query for an out-of-range * leaf as if the highest basic leaf (i.e. CPUID.0H:EAX) were * requested. AMD CPUID semantics returns all zeroes for any * undefined leaf, whether or not the leaf is in range. */ if (!entry && check_limit && !guest_cpuid_is_amd(vcpu) && !cpuid_function_in_range(vcpu, function)) { max = kvm_find_cpuid_entry(vcpu, 0, 0); if (max) { function = max->eax; entry = kvm_find_cpuid_entry(vcpu, function, index); } } if (entry) { *eax = entry->eax; *ebx = entry->ebx; *ecx = entry->ecx; *edx = entry->edx; if (function == 7 && index == 0) { u64 data; if (!__kvm_get_msr(vcpu, MSR_IA32_TSX_CTRL, &data, true) && (data & TSX_CTRL_CPUID_CLEAR)) *ebx &= ~(F(RTM) | F(HLE)); } } else { *eax = *ebx = *ecx = *edx = 0; /* * When leaf 0BH or 1FH is defined, CL is pass-through * and EDX is always the x2APIC ID, even for undefined * subleaves. Index 1 will exist iff the leaf is * implemented, so we pass through CL iff leaf 1 * exists. EDX can be copied from any existing index. */ if (function == 0xb || function == 0x1f) { entry = kvm_find_cpuid_entry(vcpu, function, 1); if (entry) { *ecx = index & 0xff; *edx = entry->edx; } } } trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx, found); return found; } EXPORT_SYMBOL_GPL(kvm_cpuid); int kvm_emulate_cpuid(struct kvm_vcpu *vcpu) { u32 eax, ebx, ecx, edx; if (cpuid_fault_enabled(vcpu) && !kvm_require_cpl(vcpu, 0)) return 1; eax = kvm_rax_read(vcpu); ecx = kvm_rcx_read(vcpu); kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx, true); kvm_rax_write(vcpu, eax); kvm_rbx_write(vcpu, ebx); kvm_rcx_write(vcpu, ecx); kvm_rdx_write(vcpu, edx); return kvm_skip_emulated_instruction(vcpu); } EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);