[PATCH v2 3/8] KVM: SVM: Check for an unexpected VM-Exit after RETPOLINE "fast" handling

From: Sean Christopherson

Date: Tue Dec 30 2025 - 16:13:56 EST


Check for an unexpected/unhandled VM-Exit after the manual RETPOLINE=y
handling. The entire point of the RETPOLINE checks is to optimize for
common VM-Exits, i.e. checking for the rare case of an unsupported
VM-Exit is counter-productive. This also aligns SVM and VMX exit handling.

No functional change intended.

Reviewed-by: Yosry Ahmed <yosry.ahmed@xxxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/svm/svm.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index a523011f0923..e24bedf1fc81 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3445,12 +3445,6 @@ static void dump_vmcb(struct kvm_vcpu *vcpu)

int svm_invoke_exit_handler(struct kvm_vcpu *vcpu, u64 exit_code)
{
- if (exit_code >= ARRAY_SIZE(svm_exit_handlers))
- goto unexpected_vmexit;
-
- if (!svm_exit_handlers[exit_code])
- goto unexpected_vmexit;
-
#ifdef CONFIG_MITIGATION_RETPOLINE
if (exit_code == SVM_EXIT_MSR)
return msr_interception(vcpu);
@@ -3467,6 +3461,12 @@ int svm_invoke_exit_handler(struct kvm_vcpu *vcpu, u64 exit_code)
return sev_handle_vmgexit(vcpu);
#endif
#endif
+ if (exit_code >= ARRAY_SIZE(svm_exit_handlers))
+ goto unexpected_vmexit;
+
+ if (!svm_exit_handlers[exit_code])
+ goto unexpected_vmexit;
+
return svm_exit_handlers[exit_code](vcpu);

unexpected_vmexit:
--
2.52.0.351.gbe84eed79e-goog