diff options
Diffstat (limited to 'arch/x86/kvm/svm/sev.c')
| -rw-r--r-- | arch/x86/kvm/svm/sev.c | 45 |
1 files changed, 29 insertions, 16 deletions
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 943bd074a5d3..a2a794c32050 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -3051,11 +3051,11 @@ out: min_sev_asid, max_sev_asid); if (boot_cpu_has(X86_FEATURE_SEV_ES)) pr_info("SEV-ES %s (ASIDs %u - %u)\n", - sev_es_supported ? "enabled" : "disabled", + str_enabled_disabled(sev_es_supported), min_sev_asid > 1 ? 1 : 0, min_sev_asid - 1); if (boot_cpu_has(X86_FEATURE_SEV_SNP)) pr_info("SEV-SNP %s (ASIDs %u - %u)\n", - sev_snp_supported ? "enabled" : "disabled", + str_enabled_disabled(sev_snp_supported), min_sev_asid > 1 ? 1 : 0, min_sev_asid - 1); sev_enabled = sev_supported; @@ -3627,13 +3627,20 @@ static int snp_begin_psc_msr(struct vcpu_svm *svm, u64 ghcb_msr) return 1; /* resume guest */ } - if (!(vcpu->kvm->arch.hypercall_exit_enabled & (1 << KVM_HC_MAP_GPA_RANGE))) { + if (!user_exit_on_hypercall(vcpu->kvm, KVM_HC_MAP_GPA_RANGE)) { set_ghcb_msr(svm, GHCB_MSR_PSC_RESP_ERROR); return 1; /* resume guest */ } vcpu->run->exit_reason = KVM_EXIT_HYPERCALL; vcpu->run->hypercall.nr = KVM_HC_MAP_GPA_RANGE; + /* + * In principle this should have been -KVM_ENOSYS, but userspace (QEMU <=9.2) + * assumed that vcpu->run->hypercall.ret is never changed by KVM and thus that + * it was always zero on KVM_EXIT_HYPERCALL. Since KVM is now overwriting + * vcpu->run->hypercall.ret, ensuring that it is zero to not break QEMU. + */ + vcpu->run->hypercall.ret = 0; vcpu->run->hypercall.args[0] = gpa; vcpu->run->hypercall.args[1] = 1; vcpu->run->hypercall.args[2] = (op == SNP_PAGE_STATE_PRIVATE) @@ -3710,7 +3717,7 @@ static int snp_begin_psc(struct vcpu_svm *svm, struct psc_buffer *psc) bool huge; u64 gfn; - if (!(vcpu->kvm->arch.hypercall_exit_enabled & (1 << KVM_HC_MAP_GPA_RANGE))) { + if (!user_exit_on_hypercall(vcpu->kvm, KVM_HC_MAP_GPA_RANGE)) { snp_complete_psc(svm, VMGEXIT_PSC_ERROR_GENERIC); return 1; } @@ -3797,6 +3804,13 @@ next_range: case VMGEXIT_PSC_OP_SHARED: vcpu->run->exit_reason = KVM_EXIT_HYPERCALL; vcpu->run->hypercall.nr = KVM_HC_MAP_GPA_RANGE; + /* + * In principle this should have been -KVM_ENOSYS, but userspace (QEMU <=9.2) + * assumed that vcpu->run->hypercall.ret is never changed by KVM and thus that + * it was always zero on KVM_EXIT_HYPERCALL. Since KVM is now overwriting + * vcpu->run->hypercall.ret, ensuring that it is zero to not break QEMU. + */ + vcpu->run->hypercall.ret = 0; vcpu->run->hypercall.args[0] = gfn_to_gpa(gfn); vcpu->run->hypercall.args[1] = npages; vcpu->run->hypercall.args[2] = entry_start.operation == VMGEXIT_PSC_OP_PRIVATE @@ -3820,7 +3834,7 @@ next_range: goto next_range; } - unreachable(); + BUG(); } static int __sev_snp_update_protected_guest_state(struct kvm_vcpu *vcpu) @@ -4435,8 +4449,8 @@ static void sev_es_vcpu_after_set_cpuid(struct vcpu_svm *svm) struct kvm_vcpu *vcpu = &svm->vcpu; if (boot_cpu_has(X86_FEATURE_V_TSC_AUX)) { - bool v_tsc_aux = guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP) || - guest_cpuid_has(vcpu, X86_FEATURE_RDPID); + bool v_tsc_aux = guest_cpu_cap_has(vcpu, X86_FEATURE_RDTSCP) || + guest_cpu_cap_has(vcpu, X86_FEATURE_RDPID); set_msr_interception(vcpu, svm->msrpm, MSR_TSC_AUX, v_tsc_aux, v_tsc_aux); } @@ -4445,16 +4459,15 @@ static void sev_es_vcpu_after_set_cpuid(struct vcpu_svm *svm) * For SEV-ES, accesses to MSR_IA32_XSS should not be intercepted if * the host/guest supports its use. * - * guest_can_use() checks a number of requirements on the host/guest to - * ensure that MSR_IA32_XSS is available, but it might report true even - * if X86_FEATURE_XSAVES isn't configured in the guest to ensure host - * MSR_IA32_XSS is always properly restored. For SEV-ES, it is better - * to further check that the guest CPUID actually supports - * X86_FEATURE_XSAVES so that accesses to MSR_IA32_XSS by misbehaved - * guests will still get intercepted and caught in the normal - * kvm_emulate_rdmsr()/kvm_emulated_wrmsr() paths. + * KVM treats the guest as being capable of using XSAVES even if XSAVES + * isn't enabled in guest CPUID as there is no intercept for XSAVES, + * i.e. the guest can use XSAVES/XRSTOR to read/write XSS if XSAVE is + * exposed to the guest and XSAVES is supported in hardware. Condition + * full XSS passthrough on the guest being able to use XSAVES *and* + * XSAVES being exposed to the guest so that KVM can at least honor + * guest CPUID for RDMSR and WRMSR. */ - if (guest_can_use(vcpu, X86_FEATURE_XSAVES) && + if (guest_cpu_cap_has(vcpu, X86_FEATURE_XSAVES) && guest_cpuid_has(vcpu, X86_FEATURE_XSAVES)) set_msr_interception(vcpu, svm->msrpm, MSR_IA32_XSS, 1, 1); else |