kernel_optimize_test/virt/kvm
Zhang Haoyu 184564efae kvm: ioapic: conditionally delay irq delivery duringeoi broadcast
Currently, we call ioapic_service() immediately when we find the irq is still
active during eoi broadcast. But for real hardware, there's some delay between
the EOI writing and irq delivery.  If we do not emulate this behavior, and
re-inject the interrupt immediately after the guest sends an EOI and re-enables
interrupts, a guest might spend all its time in the ISR if it has a broken
handler for a level-triggered interrupt.

Such livelock actually happens with Windows guests when resuming from
hibernation.

As there's no way to recognize the broken handle from new raised ones, this patch
delays an interrupt if 10.000 consecutive EOIs found that the interrupt was
still high.  The guest can then make a little forward progress, until a proper
IRQ handler is set or until some detection routine in the guest (such as
Linux's note_interrupt()) recognizes the situation.

Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Zhang Haoyu <zhanghy@sangfor.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-16 14:44:48 +02:00
..
arm KVM/ARM New features for 3.17 include: 2014-08-05 09:47:45 +02:00
assigned-dev.c virt/kvm/assigned-dev.c: Set 'dev->irq_source_id' to '-1' after free it 2014-08-19 15:12:28 +02:00
async_pf.c At over 200 commits, covering almost all supported architectures, this 2014-06-04 08:47:12 -07:00
async_pf.h
coalesced_mmio.c
coalesced_mmio.h
eventfd.c KVM: Move more code under CONFIG_HAVE_KVM_IRQFD 2014-08-06 14:24:47 +02:00
ioapic.c kvm: ioapic: conditionally delay irq delivery duringeoi broadcast 2014-09-16 14:44:48 +02:00
ioapic.h kvm: ioapic: conditionally delay irq delivery duringeoi broadcast 2014-09-16 14:44:48 +02:00
iodev.h
iommu.c kvm: iommu: fix the third parameter of kvm_iommu_put_pages (CVE-2014-3601) 2014-08-19 15:04:45 +02:00
irq_comm.c KVM: Move all accesses to kvm::irq_routing into irqchip.c 2014-08-05 14:26:20 +02:00
irqchip.c KVM: Move irq notifier implementation into eventfd.c 2014-08-05 14:26:24 +02:00
Kconfig KVM: Give IRQFD its own separate enabling Kconfig option 2014-08-05 14:26:28 +02:00
kvm_main.c KVM: remove redundant assignments in __kvm_set_memory_region 2014-09-05 12:01:15 +02:00
vfio.c