diff options
| -rw-r--r-- | arch/x86/kvm/vmx/nested.c | 8 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 7 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.h | 15 |
3 files changed, 23 insertions, 7 deletions
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 4a53e0c73445..38015f4ecc54 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -2520,11 +2520,11 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, vmcs_write64(GUEST_IA32_DEBUGCTL, vmcs12->guest_ia32_debugctl); } else { kvm_set_dr(vcpu, 7, vcpu->arch.dr7); - vmcs_write64(GUEST_IA32_DEBUGCTL, vmx->nested.vmcs01_debugctl); + vmcs_write64(GUEST_IA32_DEBUGCTL, vmx->nested.pre_vmenter_debugctl); } if (kvm_mpx_supported() && (!vmx->nested.nested_run_pending || !(vmcs12->vm_entry_controls & VM_ENTRY_LOAD_BNDCFGS))) - vmcs_write64(GUEST_BNDCFGS, vmx->nested.vmcs01_guest_bndcfgs); + vmcs_write64(GUEST_BNDCFGS, vmx->nested.pre_vmenter_bndcfgs); vmx_set_rflags(vcpu, vmcs12->guest_rflags); /* EXCEPTION_BITMAP and CR0_GUEST_HOST_MASK should basically be the @@ -3381,11 +3381,11 @@ enum nvmx_vmentry_status nested_vmx_enter_non_root_mode(struct kvm_vcpu *vcpu, if (!vmx->nested.nested_run_pending || !(vmcs12->vm_entry_controls & VM_ENTRY_LOAD_DEBUG_CONTROLS)) - vmx->nested.vmcs01_debugctl = vmcs_read64(GUEST_IA32_DEBUGCTL); + vmx->nested.pre_vmenter_debugctl = vmcs_read64(GUEST_IA32_DEBUGCTL); if (kvm_mpx_supported() && (!vmx->nested.nested_run_pending || !(vmcs12->vm_entry_controls & VM_ENTRY_LOAD_BNDCFGS))) - vmx->nested.vmcs01_guest_bndcfgs = vmcs_read64(GUEST_BNDCFGS); + vmx->nested.pre_vmenter_bndcfgs = vmcs_read64(GUEST_BNDCFGS); /* * Overwrite vmcs01.GUEST_CR3 with L1's CR3 if EPT is disabled *and* diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 61962f3c4b28..b4d3820e9800 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7847,6 +7847,13 @@ static int vmx_enter_smm(struct kvm_vcpu *vcpu, char *smstate) { struct vcpu_vmx *vmx = to_vmx(vcpu); + /* + * TODO: Implement custom flows for forcing the vCPU out/in of L2 on + * SMI and RSM. Using the common VM-Exit + VM-Enter routines is wrong + * SMI and RSM only modify state that is saved and restored via SMRAM. + * E.g. most MSRs are left untouched, but many are modified by VM-Exit + * and VM-Enter, and thus L2's values may be corrupted on SMI+RSM. + */ vmx->nested.smm.guest_mode = is_guest_mode(vcpu); if (vmx->nested.smm.guest_mode) nested_vmx_vmexit(vcpu, -1, 0, 0); diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index 71bcb486e73f..a84c91ee2a48 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -219,9 +219,18 @@ struct nested_vmx { bool has_preemption_timer_deadline; bool preemption_timer_expired; - /* to migrate it to L2 if VM_ENTRY_LOAD_DEBUG_CONTROLS is off */ - u64 vmcs01_debugctl; - u64 vmcs01_guest_bndcfgs; + /* + * Used to snapshot MSRs that are conditionally loaded on VM-Enter in + * order to propagate the guest's pre-VM-Enter value into vmcs02. For + * emulation of VMLAUNCH/VMRESUME, the snapshot will be of L1's value. + * For KVM_SET_NESTED_STATE, the snapshot is of L2's value, _if_ + * userspace restores MSRs before nested state. If userspace restores + * MSRs after nested state, the snapshot holds garbage, but KVM can't + * detect that, and the garbage value in vmcs02 will be overwritten by + * MSR restoration in any case. + */ + u64 pre_vmenter_debugctl; + u64 pre_vmenter_bndcfgs; /* to migrate it to L1 if L2 writes to L1's CR8 directly */ int l1_tpr_threshold; |