[PATCH v2 2/4] KVM: ioapic: clear IRR for edge-triggered interrupts at delivery

From: Paolo Bonzini
Date: Fri Mar 21 2014 - 05:30:49 EST


This ensures that IRR bits are set in the KVM_GET_IRQCHIP result only if
the interrupt is still sitting in the IOAPIC. After the next patches, it
avoids spurious reinjection of the interrupt when KVM_SET_IRQCHIP is
called.

Reviewed-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
virt/kvm/ioapic.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
index 0b4914147b9d..25e16a6898ed 100644
--- a/virt/kvm/ioapic.c
+++ b/virt/kvm/ioapic.c
@@ -288,6 +288,9 @@ static int ioapic_service(struct kvm_ioapic *ioapic, int irq, bool line_status)
irqe.level = 1;
irqe.shorthand = 0;

+ if (irqe.trig_mode == IOAPIC_EDGE_TRIG)
+ ioapic->irr &= ~(1 << irq);
+
if (irq == RTC_GSI && line_status) {
BUG_ON(ioapic->rtc_status.pending_eoi != 0);
ret = kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe,
--
1.8.3.1


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