[PATCH v3 50/62] KVM: x86: WARN if IRQ bypass isn't supported in kvm_pi_update_irte()

Sean Christopherson
2025-06-11T22:48:23Z

WARN if kvm_pi_update_irte() is reached without IRQ bypass support, as the
code is only reachable if the VM already has an IRQ bypass producer (see
kvm_irq_routing_update()), or from kvm_arch_irq_bypass_{add,del}_producer(),
which, stating the obvious, are called if and only if KVM enables its IRQ
bypass hooks.

Cc: David Matlack <dmatlack@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/irq.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index 45cb9f1ee618..9c03a67fedbe 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -517,7 +517,7 @@ static int kvm_pi_update_irte(struct kvm_kernel_irqfd *irqfd,
struct kvm_lapic_irq irq;
int r;

- if (!irqchip_in_kernel(kvm) || !kvm_arch_has_irq_bypass())
+ if (!irqchip_in_kernel(kvm) || WARN_ON_ONCE(!kvm_arch_has_irq_bypass()))
return 0;

if (entry && entry->type == KVM_IRQ_ROUTING_MSI) {
--
2.50.0.rc1.591.g9c95f17f64-goog