Limit KVM's incorrect check for VMXEXIT_INVALID, a.k.a. SVM_EXIT_ERR, to running as a VM, as detected by X86_FEATURE_HYPERVISOR. The exit_code and all failure codes, e.g. VMXEXIT_INVALID, are 64-bit values, and so checking only bits 31:0 could result in false positives when running on non-broken hardware, e.g. in the extremely unlikely scenario exit code 0xffffffffull is ever generated by hardware.
Keep the 32-bit check to play nice with running on broken KVM (for years, KVM has not set bits 63:32 when synthesizing nested SVM VM-Exits). Reviewed-by: Yosry Ahmed <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> --- arch/x86/kvm/svm/svm.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index 105f1394026e..f938679c0231 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -425,7 +425,10 @@ static __always_inline struct vcpu_svm *to_svm(struct kvm_vcpu *vcpu) static inline bool svm_is_vmrun_failure(u64 exit_code) { - return (u32)exit_code == (u32)SVM_EXIT_ERR; + if (cpu_feature_enabled(X86_FEATURE_HYPERVISOR)) + return (u32)exit_code == (u32)SVM_EXIT_ERR; + + return exit_code == SVM_EXIT_ERR; } /* -- 2.52.0.351.gbe84eed79e-goog
