From 8c23670f2b0004edb8f7135e314114f0c3452085 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Thu, 5 Sep 2024 21:34:09 -0700 Subject: [PATCH] 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 --- arch/x86/kvm/vmx/nested.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 1a6dc85cde18..e57cd849354b 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);