[PATCH 2/5] KVM: x86: ioapic: Don't fire level irq when Remote IRR set

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Avoid firing a level-triggered interrupt that has the Remote IRR bit set,
because that means that some CPU is already processing it. The Remote
IRR bit will be cleared after an EOI and the interrupt will refire
if the irq line is still asserted.

This behavior is aligned with QEMU's IOAPIC implementation that was
introduced by commit f99b86b94987
("x86: ioapic: ignore level irq during processing") in QEMU.

Signed-off-by: Nikita Leshenko <nikita.leshchenko@xxxxxxxxxx>
Reviewed-by: Liran Alon <liran.alon@xxxxxxxxxx>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
---
 arch/x86/kvm/ioapic.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index ae0a7dc318b2..5c9231139243 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -323,7 +323,9 @@ static int ioapic_service(struct kvm_ioapic *ioapic, int irq, bool line_status)
 	struct kvm_lapic_irq irqe;
 	int ret;
 
-	if (entry->fields.mask)
+	if (entry->fields.mask ||
+	    (entry->fields.trig_mode == IOAPIC_LEVEL_TRIG &&
+	    entry->fields.remote_irr))
 		return -1;
 
 	ioapic_debug("dest=%x dest_mode=%x delivery_mode=%x "
-- 
2.13.3




[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux