diff options
Diffstat (limited to 'arch/x86/kvm/vmx/vmx.c')
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 67 |
1 files changed, 45 insertions, 22 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 9453743ce0c4..0dbf94eb954f 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1363,6 +1363,11 @@ void vmx_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags) vmx->emulation_required = vmx_emulation_required(vcpu); } +static bool vmx_get_if_flag(struct kvm_vcpu *vcpu) +{ + return vmx_get_rflags(vcpu) & X86_EFLAGS_IF; +} + u32 vmx_get_interrupt_shadow(struct kvm_vcpu *vcpu) { u32 interruptibility = vmcs_read32(GUEST_INTERRUPTIBILITY_INFO); @@ -2646,15 +2651,6 @@ int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs) if (!loaded_vmcs->msr_bitmap) goto out_vmcs; memset(loaded_vmcs->msr_bitmap, 0xff, PAGE_SIZE); - - if (IS_ENABLED(CONFIG_HYPERV) && - static_branch_unlikely(&enable_evmcs) && - (ms_hyperv.nested_features & HV_X64_NESTED_MSR_BITMAP)) { - struct hv_enlightened_vmcs *evmcs = - (struct hv_enlightened_vmcs *)loaded_vmcs->vmcs; - - evmcs->hv_enlightenments_control.msr_bitmap = 1; - } } memset(&loaded_vmcs->host_state, 0, sizeof(struct vmcs_host_state)); @@ -3968,8 +3964,7 @@ static int vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector) if (pi_test_and_set_on(&vmx->pi_desc)) return 0; - if (vcpu != kvm_get_running_vcpu() && - !kvm_vcpu_trigger_posted_interrupt(vcpu, false)) + if (!kvm_vcpu_trigger_posted_interrupt(vcpu, false)) kvm_vcpu_kick(vcpu); return 0; @@ -5886,18 +5881,14 @@ static int __vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath) vmx_flush_pml_buffer(vcpu); /* - * We should never reach this point with a pending nested VM-Enter, and - * more specifically emulation of L2 due to invalid guest state (see - * below) should never happen as that means we incorrectly allowed a - * nested VM-Enter with an invalid vmcs12. + * KVM should never reach this point with a pending nested VM-Enter. + * More specifically, short-circuiting VM-Entry to emulate L2 due to + * invalid guest state should never happen as that means KVM knowingly + * allowed a nested VM-Enter with an invalid vmcs12. More below. */ if (KVM_BUG_ON(vmx->nested.nested_run_pending, vcpu->kvm)) return -EIO; - /* If guest state is invalid, start emulating */ - if (vmx->emulation_required) - return handle_invalid_guest_state(vcpu); - if (is_guest_mode(vcpu)) { /* * PML is never enabled when running L2, bail immediately if a @@ -5919,10 +5910,30 @@ static int __vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath) */ nested_mark_vmcs12_pages_dirty(vcpu); + /* + * Synthesize a triple fault if L2 state is invalid. In normal + * operation, nested VM-Enter rejects any attempt to enter L2 + * with invalid state. However, those checks are skipped if + * state is being stuffed via RSM or KVM_SET_NESTED_STATE. If + * L2 state is invalid, it means either L1 modified SMRAM state + * or userspace provided bad state. Synthesize TRIPLE_FAULT as + * doing so is architecturally allowed in the RSM case, and is + * the least awful solution for the userspace case without + * risking false positives. + */ + if (vmx->emulation_required) { + nested_vmx_vmexit(vcpu, EXIT_REASON_TRIPLE_FAULT, 0, 0); + return 1; + } + if (nested_vmx_reflect_vmexit(vcpu)) return 1; } + /* If guest state is invalid, start emulating. L2 is handled above. */ + if (vmx->emulation_required) + return handle_invalid_guest_state(vcpu); + if (exit_reason.failed_vmentry) { dump_vmcs(vcpu); vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY; @@ -6617,9 +6628,7 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu) * consistency check VM-Exit due to invalid guest state and bail. */ if (unlikely(vmx->emulation_required)) { - - /* We don't emulate invalid state of a nested guest */ - vmx->fail = is_guest_mode(vcpu); + vmx->fail = 0; vmx->exit_reason.full = EXIT_REASON_INVALID_STATE; vmx->exit_reason.failed_vmentry = 1; @@ -6842,6 +6851,19 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu) if (err < 0) goto free_pml; + /* + * Use Hyper-V 'Enlightened MSR Bitmap' feature when KVM runs as a + * nested (L1) hypervisor and Hyper-V in L0 supports it. Enable the + * feature only for vmcs01, KVM currently isn't equipped to realize any + * performance benefits from enabling it for vmcs02. + */ + if (IS_ENABLED(CONFIG_HYPERV) && static_branch_unlikely(&enable_evmcs) && + (ms_hyperv.nested_features & HV_X64_NESTED_MSR_BITMAP)) { + struct hv_enlightened_vmcs *evmcs = (void *)vmx->vmcs01.vmcs; + + evmcs->hv_enlightenments_control.msr_bitmap = 1; + } + /* The MSR bitmap starts with all ones */ bitmap_fill(vmx->shadow_msr_intercept.read, MAX_POSSIBLE_PASSTHROUGH_MSRS); bitmap_fill(vmx->shadow_msr_intercept.write, MAX_POSSIBLE_PASSTHROUGH_MSRS); @@ -7575,6 +7597,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = { .cache_reg = vmx_cache_reg, .get_rflags = vmx_get_rflags, .set_rflags = vmx_set_rflags, + .get_if_flag = vmx_get_if_flag, .tlb_flush_all = vmx_flush_tlb_all, .tlb_flush_current = vmx_flush_tlb_current, |