On Thu, Nov 13, 2025 at 02:56:13PM -0800, Sean Christopherson wrote: > Explicitly clear exit_code_hi in the VMCB when synthesizing "normal" > nested VM-Exits, as the full exit code is a 64-bit value (spoiler alert), > and all exit codes for non-failing VMRUN use only bits 31:0. > > Cc: Jim Mattson <[email protected]> > Cc: Yosry Ahmed <[email protected]> > Cc: [email protected] > Signed-off-by: Sean Christopherson <[email protected]>
Reviewed-by: Yosry Ahmed <[email protected]> > --- > arch/x86/kvm/svm/svm.c | 2 ++ > arch/x86/kvm/svm/svm.h | 7 ++++--- > 2 files changed, 6 insertions(+), 3 deletions(-) > > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c > index fc42bcdbb520..7ea034ee6b6c 100644 > --- a/arch/x86/kvm/svm/svm.c > +++ b/arch/x86/kvm/svm/svm.c > @@ -2433,6 +2433,7 @@ static bool check_selective_cr0_intercepted(struct > kvm_vcpu *vcpu, > > if (cr0 ^ val) { > svm->vmcb->control.exit_code = SVM_EXIT_CR0_SEL_WRITE; > + svm->vmcb->control.exit_code_hi = 0; > ret = (nested_svm_exit_handled(svm) == NESTED_EXIT_DONE); > } > > @@ -4608,6 +4609,7 @@ static int svm_check_intercept(struct kvm_vcpu *vcpu, > if (static_cpu_has(X86_FEATURE_NRIPS)) > vmcb->control.next_rip = info->next_rip; > vmcb->control.exit_code = icpt_info.exit_code; > + vmcb->control.exit_code_hi = 0; > vmexit = nested_svm_exit_handled(svm); > > ret = (vmexit == NESTED_EXIT_DONE) ? X86EMUL_INTERCEPTED > diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h > index c2acaa49ee1c..253a8dca412c 100644 > --- a/arch/x86/kvm/svm/svm.h > +++ b/arch/x86/kvm/svm/svm.h > @@ -763,9 +763,10 @@ int nested_svm_vmexit(struct vcpu_svm *svm); > > static inline int nested_svm_simple_vmexit(struct vcpu_svm *svm, u32 > exit_code) > { > - svm->vmcb->control.exit_code = exit_code; > - svm->vmcb->control.exit_info_1 = 0; > - svm->vmcb->control.exit_info_2 = 0; > + svm->vmcb->control.exit_code = exit_code; > + svm->vmcb->control.exit_code_hi = 0; > + svm->vmcb->control.exit_info_1 = 0; > + svm->vmcb->control.exit_info_2 = 0; > return nested_svm_vmexit(svm); > } > > -- > 2.52.0.rc1.455.g30608eb744-goog >
