From: Sean Christopherson Date: Fri, 6 Sep 2024 04:34:09 +0000 (-0700) Subject: KVM: nVMX: Suppress external interrupt VM-Exit injection if there's no IRQ X-Git-Tag: v6.12-rc1~11^2~1^2~5 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8c23670f2b0004edb8f7135e314114f0c3452085;p=thirdparty%2Flinux.git KVM: nVMX: Suppress external interrupt VM-Exit injection if there's no IRQ In the should-be-impossible scenario that kvm_cpu_get_interrupt() doesn't return a valid vector after checking kvm_cpu_has_interrupt(), skip VM-Exit injection to reduce the probability of crashing/confusing L1. Now that KVM gets the IRQ _before_ calling nested_vmx_vmexit(), squashing the VM-Exit injection is trivial since there are no actions that need to be undone. Reviewed-by: Chao Gao Link: https://lore.kernel.org/r/20240906043413.1049633-4-seanjc@google.com Signed-off-by: Sean Christopherson --- diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 1a6dc85cde180..e57cd849354b0 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -4305,7 +4305,8 @@ static int vmx_check_nested_events(struct kvm_vcpu *vcpu) } irq = kvm_apic_has_interrupt(vcpu); - WARN_ON_ONCE(irq < 0); + if (WARN_ON_ONCE(irq < 0)) + goto no_vmexit; nested_vmx_vmexit(vcpu, EXIT_REASON_EXTERNAL_INTERRUPT, INTR_INFO_VALID_MASK | INTR_TYPE_EXT_INTR | irq, 0);