KVM: x86: ioapic: Don't fire level irq when Remote IRR set

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@oracle.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
This commit is contained in:
Nikita Leshenko 2017-11-05 15:52:30 +02:00 committed by Paolo Bonzini
parent 0fc5a36dd6
commit da3fe7bdfa
1 changed files with 3 additions and 1 deletions

View File

@ -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 "