From e27fc915c8f575ab5630e27d97465c2077d4b9d1 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Fri, 4 Sep 2026 10:06:40 -0700 Subject: [PATCH] KVM: SVM: Update control fields on #VMEXIT if and only if VMRUN succeeded Leave control.erap_ctl and control.clean as-is in the VMCS if VMRUN fails, because as per AMD: there's no explicit architectural guarantee about the behavior in the presence of VMRUN failures. So the best thing to do would be to assume that if VMRUN fails, the actions requested in the control fields may not have been performed. Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson Message-ID: <20260904170642.3291466-3-seanjc@google.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/svm/svm.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index afbaaaab84ed..b63e7c69aa1c 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -4625,17 +4625,17 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags) if (!svm_is_vmrun_failure(svm->vmcb->control.exit_code)) { this_cpu_ptr(&svm_data)->flush_all_asids = false; svm->vmcb->control.tlb_ctl = TLB_CONTROL_DO_NOTHING; + + /* + * Unconditionally mask off the CLEAR_RAP bit, the AND is just + * as cheap as the TEST+Jcc to avoid it. + */ + if (cpu_feature_enabled(X86_FEATURE_ERAPS)) + svm->vmcb->control.erap_ctl &= ~ERAP_CONTROL_CLEAR_RAP; + + vmcb_mark_all_clean(svm->vmcb); } - /* - * Unconditionally mask off the CLEAR_RAP bit, the AND is just as cheap - * as the TEST+Jcc to avoid it. - */ - if (cpu_feature_enabled(X86_FEATURE_ERAPS)) - svm->vmcb->control.erap_ctl &= ~ERAP_CONTROL_CLEAR_RAP; - - vmcb_mark_all_clean(svm->vmcb); - /* if exit due to PF check for async PF */ if (svm->vmcb->control.exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR) vcpu->arch.apf.host_apf_flags =