diff options
Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r-- | arch/x86/kvm/x86.c | 256 |
1 files changed, 169 insertions, 87 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2b1d82647195..ceb7c5e9cf9e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -196,7 +196,7 @@ bool __read_mostly eager_page_split = true; module_param(eager_page_split, bool, 0644); /* Enable/disable SMT_RSB bug mitigation */ -bool __read_mostly mitigate_smt_rsb; +static bool __read_mostly mitigate_smt_rsb; module_param(mitigate_smt_rsb, bool, 0444); /* @@ -804,8 +804,8 @@ void kvm_inject_emulated_page_fault(struct kvm_vcpu *vcpu, */ if ((fault->error_code & PFERR_PRESENT_MASK) && !(fault->error_code & PFERR_RSVD_MASK)) - kvm_mmu_invalidate_gva(vcpu, fault_mmu, fault->address, - fault_mmu->root.hpa); + kvm_mmu_invalidate_addr(vcpu, fault_mmu, fault->address, + KVM_MMU_ROOT_CURRENT); fault_mmu->inject_page_fault(vcpu, fault); } @@ -843,7 +843,7 @@ bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl) bool kvm_require_dr(struct kvm_vcpu *vcpu, int dr) { - if ((dr != 4 && dr != 5) || !kvm_read_cr4_bits(vcpu, X86_CR4_DE)) + if ((dr != 4 && dr != 5) || !kvm_is_cr4_bit_set(vcpu, X86_CR4_DE)) return true; kvm_queue_exception(vcpu, UD_VECTOR); @@ -908,6 +908,24 @@ EXPORT_SYMBOL_GPL(load_pdptrs); void kvm_post_set_cr0(struct kvm_vcpu *vcpu, unsigned long old_cr0, unsigned long cr0) { + /* + * CR0.WP is incorporated into the MMU role, but only for non-nested, + * indirect shadow MMUs. If paging is disabled, no updates are needed + * as there are no permission bits to emulate. If TDP is enabled, the + * MMU's metadata needs to be updated, e.g. so that emulating guest + * translations does the right thing, but there's no need to unload the + * root as CR0.WP doesn't affect SPTEs. + */ + if ((cr0 ^ old_cr0) == X86_CR0_WP) { + if (!(cr0 & X86_CR0_PG)) + return; + + if (tdp_enabled) { + kvm_init_mmu(vcpu); + return; + } + } + if ((cr0 ^ old_cr0) & X86_CR0_PG) { kvm_clear_async_pf_completion_queue(vcpu); kvm_async_pf_hash_reset(vcpu); @@ -967,7 +985,7 @@ int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) return 1; if (!(cr0 & X86_CR0_PG) && - (is_64_bit_mode(vcpu) || kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE))) + (is_64_bit_mode(vcpu) || kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE))) return 1; static_call(kvm_x86_set_cr0)(vcpu, cr0); @@ -989,7 +1007,7 @@ void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu) if (vcpu->arch.guest_state_protected) return; - if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE)) { + if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) { if (vcpu->arch.xcr0 != host_xcr0) xsetbv(XCR_XFEATURE_ENABLED_MASK, vcpu->arch.xcr0); @@ -1003,7 +1021,7 @@ void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu) if (static_cpu_has(X86_FEATURE_PKU) && vcpu->arch.pkru != vcpu->arch.host_pkru && ((vcpu->arch.xcr0 & XFEATURE_MASK_PKRU) || - kvm_read_cr4_bits(vcpu, X86_CR4_PKE))) + kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE))) write_pkru(vcpu->arch.pkru); #endif /* CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS */ } @@ -1017,14 +1035,14 @@ void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu) #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS if (static_cpu_has(X86_FEATURE_PKU) && ((vcpu->arch.xcr0 & XFEATURE_MASK_PKRU) || - kvm_read_cr4_bits(vcpu, X86_CR4_PKE))) { + kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE))) { vcpu->arch.pkru = rdpkru(); if (vcpu->arch.pkru != vcpu->arch.host_pkru) write_pkru(vcpu->arch.host_pkru); } #endif /* CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS */ - if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE)) { + if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) { if (vcpu->arch.xcr0 != host_xcr0) xsetbv(XCR_XFEATURE_ENABLED_MASK, host_xcr0); @@ -1180,9 +1198,6 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) return 1; if ((cr4 & X86_CR4_PCIDE) && !(old_cr4 & X86_CR4_PCIDE)) { - if (!guest_cpuid_has(vcpu, X86_FEATURE_PCID)) - return 1; - /* PCID can not be enabled when cr3[11:0]!=000H or EFER.LMA=0 */ if ((kvm_read_cr3(vcpu) & X86_CR3_PCID_MASK) || !is_long_mode(vcpu)) return 1; @@ -1229,7 +1244,7 @@ static void kvm_invalidate_pcid(struct kvm_vcpu *vcpu, unsigned long pcid) * PCIDs for them are also 0, because MOV to CR3 always flushes the TLB * with PCIDE=0. */ - if (!kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE)) + if (!kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE)) return; for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) @@ -1244,9 +1259,7 @@ int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3) bool skip_tlb_flush = false; unsigned long pcid = 0; #ifdef CONFIG_X86_64 - bool pcid_enabled = kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE); - - if (pcid_enabled) { + if (kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE)) { skip_tlb_flush = cr3 & X86_CR3_PCID_NOFLUSH; cr3 &= ~X86_CR3_PCID_NOFLUSH; pcid = cr3 & X86_CR3_PCID_MASK; @@ -1545,39 +1558,41 @@ static u32 emulated_msrs[ARRAY_SIZE(emulated_msrs_all)]; static unsigned num_emulated_msrs; /* - * List of msr numbers which are used to expose MSR-based features that - * can be used by a hypervisor to validate requested CPU features. + * List of MSRs that control the existence of MSR-based features, i.e. MSRs + * that are effectively CPUID leafs. VMX MSRs are also included in the set of + * feature MSRs, but are handled separately to allow expedited lookups. */ -static const u32 msr_based_features_all[] = { - MSR_IA32_VMX_BASIC, - MSR_IA32_VMX_TRUE_PINBASED_CTLS, - MSR_IA32_VMX_PINBASED_CTLS, - MSR_IA32_VMX_TRUE_PROCBASED_CTLS, - MSR_IA32_VMX_PROCBASED_CTLS, - MSR_IA32_VMX_TRUE_EXIT_CTLS, - MSR_IA32_VMX_EXIT_CTLS, - MSR_IA32_VMX_TRUE_ENTRY_CTLS, - MSR_IA32_VMX_ENTRY_CTLS, - MSR_IA32_VMX_MISC, - MSR_IA32_VMX_CR0_FIXED0, - MSR_IA32_VMX_CR0_FIXED1, - MSR_IA32_VMX_CR4_FIXED0, - MSR_IA32_VMX_CR4_FIXED1, - MSR_IA32_VMX_VMCS_ENUM, - MSR_IA32_VMX_PROCBASED_CTLS2, - MSR_IA32_VMX_EPT_VPID_CAP, - MSR_IA32_VMX_VMFUNC, - +static const u32 msr_based_features_all_except_vmx[] = { MSR_AMD64_DE_CFG, MSR_IA32_UCODE_REV, MSR_IA32_ARCH_CAPABILITIES, MSR_IA32_PERF_CAPABILITIES, }; -static u32 msr_based_features[ARRAY_SIZE(msr_based_features_all)]; +static u32 msr_based_features[ARRAY_SIZE(msr_based_features_all_except_vmx) + + (KVM_LAST_EMULATED_VMX_MSR - KVM_FIRST_EMULATED_VMX_MSR + 1)]; static unsigned int num_msr_based_features; /* + * All feature MSRs except uCode revID, which tracks the currently loaded uCode + * patch, are immutable once the vCPU model is defined. + */ +static bool kvm_is_immutable_feature_msr(u32 msr) +{ + int i; + + if (msr >= KVM_FIRST_EMULATED_VMX_MSR && msr <= KVM_LAST_EMULATED_VMX_MSR) + return true; + + for (i = 0; i < ARRAY_SIZE(msr_based_features_all_except_vmx); i++) { + if (msr == msr_based_features_all_except_vmx[i]) + return msr != MSR_IA32_UCODE_REV; + } + + return false; +} + +/* * Some IA32_ARCH_CAPABILITIES bits have dependencies on MSRs that KVM * does not yet virtualize. These include: * 10 - MISC_PACKAGE_CTRLS @@ -2194,6 +2209,22 @@ static int do_get_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data) static int do_set_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data) { + u64 val; + + /* + * Disallow writes to immutable feature MSRs after KVM_RUN. KVM does + * not support modifying the guest vCPU model on the fly, e.g. changing + * the nVMX capabilities while L2 is running is nonsensical. Ignore + * writes of the same value, e.g. to allow userspace to blindly stuff + * all MSRs when emulating RESET. + */ + if (kvm_vcpu_has_run(vcpu) && kvm_is_immutable_feature_msr(index)) { + if (do_get_msr(vcpu, index, &val) || *data != val) + return -EINVAL; + + return 0; + } + return kvm_set_msr_ignored_check(vcpu, index, *data, true); } @@ -3616,9 +3647,40 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) if (data & ~kvm_caps.supported_perf_cap) return 1; + /* + * Note, this is not just a performance optimization! KVM + * disallows changing feature MSRs after the vCPU has run; PMU + * refresh will bug the VM if called after the vCPU has run. + */ + if (vcpu->arch.perf_capabilities == data) + break; + vcpu->arch.perf_capabilities = data; kvm_pmu_refresh(vcpu); - return 0; + break; + case MSR_IA32_PRED_CMD: + if (!msr_info->host_initiated && !guest_has_pred_cmd_msr(vcpu)) + return 1; + + if (!boot_cpu_has(X86_FEATURE_IBPB) || (data & ~PRED_CMD_IBPB)) + return 1; + if (!data) + break; + + wrmsrl(MSR_IA32_PRED_CMD, PRED_CMD_IBPB); + break; + case MSR_IA32_FLUSH_CMD: + if (!msr_info->host_initiated && + !guest_cpuid_has(vcpu, X86_FEATURE_FLUSH_L1D)) + return 1; + + if (!boot_cpu_has(X86_FEATURE_FLUSH_L1D) || (data & ~L1D_FLUSH)) + return 1; + if (!data) + break; + + wrmsrl(MSR_IA32_FLUSH_CMD, L1D_FLUSH); + break; case MSR_EFER: return set_efer(vcpu, msr_info); case MSR_K7_HWCR: @@ -4534,9 +4596,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) r = 0; break; case KVM_CAP_XSAVE2: { - u64 guest_perm = xstate_get_guest_group_perm(); - - r = xstate_required_size(kvm_caps.supported_xcr0 & guest_perm, false); + r = xstate_required_size(kvm_get_filtered_xcr0(), false); if (r < sizeof(struct kvm_xsave)) r = sizeof(struct kvm_xsave); break; @@ -5036,7 +5096,7 @@ static int kvm_vcpu_ioctl_x86_set_mce(struct kvm_vcpu *vcpu, return 0; if (mce->status & MCI_STATUS_UC) { if ((vcpu->arch.mcg_status & MCG_STATUS_MCIP) || - !kvm_read_cr4_bits(vcpu, X86_CR4_MCE)) { + !kvm_is_cr4_bit_set(vcpu, X86_CR4_MCE)) { kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu); return 0; } @@ -5128,7 +5188,7 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu, events->interrupt.shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu); events->nmi.injected = vcpu->arch.nmi_injected; - events->nmi.pending = vcpu->arch.nmi_pending != 0; + events->nmi.pending = kvm_get_nr_pending_nmis(vcpu); events->nmi.masked = static_call(kvm_x86_get_nmi_mask)(vcpu); /* events->sipi_vector is never valid when reporting to user space */ @@ -5215,8 +5275,11 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, events->interrupt.shadow); vcpu->arch.nmi_injected = events->nmi.injected; - if (events->flags & KVM_VCPUEVENT_VALID_NMI_PENDING) - vcpu->arch.nmi_pending = events->nmi.pending; + if (events->flags & KVM_VCPUEVENT_VALID_NMI_PENDING) { + vcpu->arch.nmi_pending = 0; + atomic_set(&vcpu->arch.nmi_queued, events->nmi.pending); + kvm_make_request(KVM_REQ_NMI, vcpu); + } static_call(kvm_x86_set_nmi_mask)(vcpu, events->nmi.masked); if (events->flags & KVM_VCPUEVENT_VALID_SIPI_VECTOR && @@ -6024,11 +6087,6 @@ static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm, return 0; } -static unsigned long kvm_vm_ioctl_get_nr_mmu_pages(struct kvm *kvm) -{ - return kvm->arch.n_max_mmu_pages; -} - static int kvm_vm_ioctl_get_irqchip(struct kvm *kvm, struct kvm_irqchip *chip) { struct kvm_pic *pic = kvm->arch.vpic; @@ -6675,8 +6733,7 @@ static int kvm_vm_ioctl_set_clock(struct kvm *kvm, void __user *argp) return 0; } -long kvm_arch_vm_ioctl(struct file *filp, - unsigned int ioctl, unsigned long arg) +int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { struct kvm *kvm = filp->private_data; void __user *argp = (void __user *)arg; @@ -6714,9 +6771,6 @@ set_identity_unlock: case KVM_SET_NR_MMU_PAGES: r = kvm_vm_ioctl_set_nr_mmu_pages(kvm, arg); break; - case KVM_GET_NR_MMU_PAGES: - r = kvm_vm_ioctl_get_nr_mmu_pages(kvm); - break; case KVM_CREATE_IRQCHIP: { mutex_lock(&kvm->lock); @@ -7021,6 +7075,18 @@ out: return r; } +static void kvm_probe_feature_msr(u32 msr_index) +{ + struct kvm_msr_entry msr = { + .index = msr_index, + }; + + if (kvm_get_msr_feature(&msr)) + return; + + msr_based_features[num_msr_based_features++] = msr_index; +} + static void kvm_probe_msr_to_save(u32 msr_index) { u32 dummy[2]; @@ -7096,7 +7162,7 @@ static void kvm_probe_msr_to_save(u32 msr_index) msrs_to_save[num_msrs_to_save++] = msr_index; } -static void kvm_init_msr_list(void) +static void kvm_init_msr_lists(void) { unsigned i; @@ -7122,15 +7188,11 @@ static void kvm_init_msr_list(void) emulated_msrs[num_emulated_msrs++] = emulated_msrs_all[i]; } - for (i = 0; i < ARRAY_SIZE(msr_based_features_all); i++) { - struct kvm_msr_entry msr; + for (i = KVM_FIRST_EMULATED_VMX_MSR; i <= KVM_LAST_EMULATED_VMX_MSR; i++) + kvm_probe_feature_msr(i); - msr.index = msr_based_features_all[i]; - if (kvm_get_msr_feature(&msr)) - continue; - - msr_based_features[num_msr_based_features++] = msr_based_features_all[i]; - } + for (i = 0; i < ARRAY_SIZE(msr_based_features_all_except_vmx); i++) + kvm_probe_feature_msr(msr_based_features_all_except_vmx[i]); } static int vcpu_mmio_write(struct kvm_vcpu *vcpu, gpa_t addr, int len, @@ -8466,7 +8528,6 @@ static int handle_emulation_failure(struct kvm_vcpu *vcpu, int emulation_type) } static bool reexecute_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, - bool write_fault_to_shadow_pgtable, int emulation_type) { gpa_t gpa = cr2_or_gpa; @@ -8537,7 +8598,7 @@ static bool reexecute_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, * be fixed by unprotecting shadow page and it should * be reported to userspace. */ - return !write_fault_to_shadow_pgtable; + return !(emulation_type & EMULTYPE_WRITE_PF_TO_SP); } static bool retry_instruction(struct x86_emulate_ctxt *ctxt, @@ -8785,20 +8846,12 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, int r; struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt; bool writeback = true; - bool write_fault_to_spt; if (unlikely(!kvm_can_emulate_insn(vcpu, emulation_type, insn, insn_len))) return 1; vcpu->arch.l1tf_flush_l1d = true; - /* - * Clear write_fault_to_shadow_pgtable here to ensure it is - * never reused. - */ - write_fault_to_spt = vcpu->arch.write_fault_to_shadow_pgtable; - vcpu->arch.write_fault_to_shadow_pgtable = false; - if (!(emulation_type & EMULTYPE_NO_DECODE)) { kvm_clear_exception_queue(vcpu); @@ -8819,7 +8872,6 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, return 1; } if (reexecute_instruction(vcpu, cr2_or_gpa, - write_fault_to_spt, emulation_type)) return 1; @@ -8898,8 +8950,7 @@ restart: return 1; if (r == EMULATION_FAILED) { - if (reexecute_instruction(vcpu, cr2_or_gpa, write_fault_to_spt, - emulation_type)) + if (reexecute_instruction(vcpu, cr2_or_gpa, emulation_type)) return 1; return handle_emulation_failure(vcpu, emulation_type); @@ -9477,7 +9528,7 @@ static int __kvm_x86_vendor_init(struct kvm_x86_init_ops *ops) kvm_caps.max_guest_tsc_khz = max; } kvm_caps.default_tsc_scaling_ratio = 1ULL << kvm_caps.tsc_scaling_ratio_frac_bits; - kvm_init_msr_list(); + kvm_init_msr_lists(); return 0; out_unwind_ops: @@ -9808,7 +9859,11 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) vcpu->run->hypercall.args[0] = gpa; vcpu->run->hypercall.args[1] = npages; vcpu->run->hypercall.args[2] = attrs; - vcpu->run->hypercall.longmode = op_64_bit; + vcpu->run->hypercall.flags = 0; + if (op_64_bit) + vcpu->run->hypercall.flags |= KVM_EXIT_HYPERCALL_LONG_MODE; + + WARN_ON_ONCE(vcpu->run->hypercall.flags & KVM_EXIT_HYPERCALL_MBZ); vcpu->arch.complete_userspace_io = complete_hypercall_exit; return 0; } @@ -10170,19 +10225,46 @@ out: static void process_nmi(struct kvm_vcpu *vcpu) { - unsigned limit = 2; + unsigned int limit; /* - * x86 is limited to one NMI running, and one NMI pending after it. - * If an NMI is already in progress, limit further NMIs to just one. - * Otherwise, allow two (and we'll inject the first one immediately). + * x86 is limited to one NMI pending, but because KVM can't react to + * incoming NMIs as quickly as bare metal, e.g. if the vCPU is + * scheduled out, KVM needs to play nice with two queued NMIs showing + * up at the same time. To handle this scenario, allow two NMIs to be + * (temporarily) pending so long as NMIs are not blocked and KVM is not + * waiting for a previous NMI injection to complete (which effectively + * blocks NMIs). KVM will immediately inject one of the two NMIs, and + * will request an NMI window to handle the second NMI. */ if (static_call(kvm_x86_get_nmi_mask)(vcpu) || vcpu->arch.nmi_injected) limit = 1; + else + limit = 2; + + /* + * Adjust the limit to account for pending virtual NMIs, which aren't + * tracked in vcpu->arch.nmi_pending. + */ + if (static_call(kvm_x86_is_vnmi_pending)(vcpu)) + limit--; vcpu->arch.nmi_pending += atomic_xchg(&vcpu->arch.nmi_queued, 0); vcpu->arch.nmi_pending = min(vcpu->arch.nmi_pending, limit); - kvm_make_request(KVM_REQ_EVENT, vcpu); + + if (vcpu->arch.nmi_pending && + (static_call(kvm_x86_set_vnmi_pending)(vcpu))) + vcpu->arch.nmi_pending--; + + if (vcpu->arch.nmi_pending) + kvm_make_request(KVM_REQ_EVENT, vcpu); +} + +/* Return total number of NMIs pending injection to the VM */ +int kvm_get_nr_pending_nmis(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.nmi_pending + + static_call(kvm_x86_is_vnmi_pending)(vcpu); } void kvm_make_scan_ioapic_request_mask(struct kvm *kvm, @@ -13268,7 +13350,7 @@ int kvm_handle_invpcid(struct kvm_vcpu *vcpu, unsigned long type, gva_t gva) return 1; } - pcid_enabled = kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE); + pcid_enabled = kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE); switch (type) { case INVPCID_TYPE_INDIV_ADDR: |