diff options
Diffstat (limited to 'arch/x86/kvm/svm/svm.c')
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 77 |
1 files changed, 70 insertions, 7 deletions
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 8834822c00cd..664d20f0689c 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -198,6 +198,11 @@ module_param(avic, bool, 0444); bool __read_mostly dump_invalid_vmcb; module_param(dump_invalid_vmcb, bool, 0644); + +bool intercept_smi = true; +module_param(intercept_smi, bool, 0444); + + static bool svm_gp_erratum_intercept = true; static u8 rsm_ins_bytes[] = "\x0f\xaa"; @@ -1185,7 +1190,10 @@ static void init_vmcb(struct kvm_vcpu *vcpu) svm_set_intercept(svm, INTERCEPT_INTR); svm_set_intercept(svm, INTERCEPT_NMI); - svm_set_intercept(svm, INTERCEPT_SMI); + + if (intercept_smi) + svm_set_intercept(svm, INTERCEPT_SMI); + svm_set_intercept(svm, INTERCEPT_SELECTIVE_CR0); svm_set_intercept(svm, INTERCEPT_RDPMC); svm_set_intercept(svm, INTERCEPT_CPUID); @@ -1923,7 +1931,7 @@ static int npf_interception(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); - u64 fault_address = __sme_clr(svm->vmcb->control.exit_info_2); + u64 fault_address = svm->vmcb->control.exit_info_2; u64 error_code = svm->vmcb->control.exit_info_1; trace_kvm_page_fault(fault_address, error_code); @@ -2106,6 +2114,11 @@ static int nmi_interception(struct kvm_vcpu *vcpu) return 1; } +static int smi_interception(struct kvm_vcpu *vcpu) +{ + return 1; +} + static int intr_interception(struct kvm_vcpu *vcpu) { ++vcpu->stat.irq_exits; @@ -2941,7 +2954,16 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr) svm_disable_lbrv(vcpu); break; case MSR_VM_HSAVE_PA: - svm->nested.hsave_msr = data; + /* + * Old kernels did not validate the value written to + * MSR_VM_HSAVE_PA. Allow KVM_SET_MSR to set an invalid + * value to allow live migrating buggy or malicious guests + * originating from those kernels. + */ + if (!msr->host_initiated && !page_address_valid(vcpu, data)) + return 1; + + svm->nested.hsave_msr = data & PAGE_MASK; break; case MSR_VM_CR: return svm_set_vm_cr(vcpu, data); @@ -3080,8 +3102,7 @@ static int (*const svm_exit_handlers[])(struct kvm_vcpu *vcpu) = { [SVM_EXIT_EXCP_BASE + GP_VECTOR] = gp_interception, [SVM_EXIT_INTR] = intr_interception, [SVM_EXIT_NMI] = nmi_interception, - [SVM_EXIT_SMI] = kvm_emulate_as_nop, - [SVM_EXIT_INIT] = kvm_emulate_as_nop, + [SVM_EXIT_SMI] = smi_interception, [SVM_EXIT_VINTR] = interrupt_window_interception, [SVM_EXIT_RDPMC] = kvm_emulate_rdpmc, [SVM_EXIT_CPUID] = kvm_emulate_cpuid, @@ -4288,6 +4309,7 @@ static int svm_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection) static int svm_enter_smm(struct kvm_vcpu *vcpu, char *smstate) { struct vcpu_svm *svm = to_svm(vcpu); + struct kvm_host_map map_save; int ret; if (is_guest_mode(vcpu)) { @@ -4303,6 +4325,29 @@ static int svm_enter_smm(struct kvm_vcpu *vcpu, char *smstate) ret = nested_svm_vmexit(svm); if (ret) return ret; + + /* + * KVM uses VMCB01 to store L1 host state while L2 runs but + * VMCB01 is going to be used during SMM and thus the state will + * be lost. Temporary save non-VMLOAD/VMSAVE state to the host save + * area pointed to by MSR_VM_HSAVE_PA. APM guarantees that the + * format of the area is identical to guest save area offsetted + * by 0x400 (matches the offset of 'struct vmcb_save_area' + * within 'struct vmcb'). Note: HSAVE area may also be used by + * L1 hypervisor to save additional host context (e.g. KVM does + * that, see svm_prepare_guest_switch()) which must be + * preserved. + */ + if (kvm_vcpu_map(vcpu, gpa_to_gfn(svm->nested.hsave_msr), + &map_save) == -EINVAL) + return 1; + + BUILD_BUG_ON(offsetof(struct vmcb, save) != 0x400); + + svm_copy_vmrun_state(&svm->vmcb01.ptr->save, + map_save.hva + 0x400); + + kvm_vcpu_unmap(vcpu, &map_save, true); } return 0; } @@ -4310,13 +4355,14 @@ static int svm_enter_smm(struct kvm_vcpu *vcpu, char *smstate) static int svm_leave_smm(struct kvm_vcpu *vcpu, const char *smstate) { struct vcpu_svm *svm = to_svm(vcpu); - struct kvm_host_map map; + struct kvm_host_map map, map_save; int ret = 0; if (guest_cpuid_has(vcpu, X86_FEATURE_LM)) { u64 saved_efer = GET_SMSTATE(u64, smstate, 0x7ed0); u64 guest = GET_SMSTATE(u64, smstate, 0x7ed8); u64 vmcb12_gpa = GET_SMSTATE(u64, smstate, 0x7ee0); + struct vmcb *vmcb12; if (guest) { if (!guest_cpuid_has(vcpu, X86_FEATURE_SVM)) @@ -4332,8 +4378,25 @@ static int svm_leave_smm(struct kvm_vcpu *vcpu, const char *smstate) if (svm_allocate_nested(svm)) return 1; - ret = enter_svm_guest_mode(vcpu, vmcb12_gpa, map.hva); + vmcb12 = map.hva; + + nested_load_control_from_vmcb12(svm, &vmcb12->control); + + ret = enter_svm_guest_mode(vcpu, vmcb12_gpa, vmcb12); kvm_vcpu_unmap(vcpu, &map, true); + + /* + * Restore L1 host state from L1 HSAVE area as VMCB01 was + * used during SMM (see svm_enter_smm()) + */ + if (kvm_vcpu_map(vcpu, gpa_to_gfn(svm->nested.hsave_msr), + &map_save) == -EINVAL) + return 1; + + svm_copy_vmrun_state(map_save.hva + 0x400, + &svm->vmcb01.ptr->save); + + kvm_vcpu_unmap(vcpu, &map_save, true); } } |