diff options
| author | John Allen <john.allen@amd.com> | 2025-09-19 15:32:42 -0700 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2025-09-23 09:26:51 -0700 |
| commit | 48b2ec0d540c29cebb5119dd2b8e8e7369bc409c (patch) | |
| tree | 26cc4c153d63fd44cdfb74d626b22b2d3f277656 | |
| parent | 42ae6448531b5106e9f29794992856e94a52b5cb (diff) | |
KVM: SVM: Emulate reads and writes to shadow stack MSRs
Emulate shadow stack MSR access by reading and writing to the
corresponding fields in the VMCB.
Signed-off-by: John Allen <john.allen@amd.com>
[sean: mark VMCB_CET dirty/clean as appropriate]
Link: https://lore.kernel.org/r/20250919223258.1604852-36-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 21 | ||||
| -rw-r--r-- | arch/x86/kvm/svm/svm.h | 3 |
2 files changed, 23 insertions, 1 deletions
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index ff4925a7bf96..b977ea4a46e7 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2767,6 +2767,15 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) if (guest_cpuid_is_intel_compatible(vcpu)) msr_info->data |= (u64)svm->sysenter_esp_hi << 32; break; + case MSR_IA32_S_CET: + msr_info->data = svm->vmcb->save.s_cet; + break; + case MSR_IA32_INT_SSP_TAB: + msr_info->data = svm->vmcb->save.isst_addr; + break; + case MSR_KVM_INTERNAL_GUEST_SSP: + msr_info->data = svm->vmcb->save.ssp; + break; case MSR_TSC_AUX: msr_info->data = svm->tsc_aux; break; @@ -2999,6 +3008,18 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr) svm->vmcb01.ptr->save.sysenter_esp = (u32)data; svm->sysenter_esp_hi = guest_cpuid_is_intel_compatible(vcpu) ? (data >> 32) : 0; break; + case MSR_IA32_S_CET: + svm->vmcb->save.s_cet = data; + vmcb_mark_dirty(svm->vmcb01.ptr, VMCB_CET); + break; + case MSR_IA32_INT_SSP_TAB: + svm->vmcb->save.isst_addr = data; + vmcb_mark_dirty(svm->vmcb01.ptr, VMCB_CET); + break; + case MSR_KVM_INTERNAL_GUEST_SSP: + svm->vmcb->save.ssp = data; + vmcb_mark_dirty(svm->vmcb01.ptr, VMCB_CET); + break; case MSR_TSC_AUX: /* * TSC_AUX is always virtualized for SEV-ES guests when the diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index 10d5cbc259e1..37de6a4a2665 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -74,6 +74,7 @@ enum { * AVIC PHYSICAL_TABLE pointer, * AVIC LOGICAL_TABLE pointer */ + VMCB_CET, /* S_CET, SSP, ISST_ADDR */ VMCB_SW = 31, /* Reserved for hypervisor/software use */ }; @@ -82,7 +83,7 @@ enum { (1U << VMCB_ASID) | (1U << VMCB_INTR) | \ (1U << VMCB_NPT) | (1U << VMCB_CR) | (1U << VMCB_DR) | \ (1U << VMCB_DT) | (1U << VMCB_SEG) | (1U << VMCB_CR2) | \ - (1U << VMCB_LBR) | (1U << VMCB_AVIC) | \ + (1U << VMCB_LBR) | (1U << VMCB_AVIC) | (1U << VMCB_CET) | \ (1U << VMCB_SW)) /* TPR and CR2 are always written before VMRUN */ |