[PATCH v3 35/62] KVM: x86: Skip IOMMU IRTE updates if there's no old or new vCPU being targeted
From: Sean Christopherson <seanjc@google.com>
Date: 2025-06-11 22:47:56
Also in:
kvm, kvmarm, linux-iommu, lkml
Subsystem:
kernel virtual machine for x86 (kvm/x86), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Sean Christopherson, Paolo Bonzini, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
Don't "reconfigure" an IRTE into host controlled mode when it's already in the state, i.e. if KVM's GSI routing changes but the IRQ wasn't and still isn't being posted to a vCPU. Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/x86/kvm/irq.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index 6447ea518d01..43e85ebc0d5b 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c@@ -542,6 +542,9 @@ static int kvm_pi_update_irte(struct kvm_kernel_irqfd *irqfd, vcpu = NULL; } + if (!irqfd->irq_bypass_vcpu && !vcpu) + return 0; + r = kvm_x86_call(pi_update_irte)(irqfd, irqfd->kvm, host_irq, irqfd->gsi, vcpu, irq.vector); if (r) {
--
2.50.0.rc1.591.g9c95f17f64-goog