From 437f9963bc4fd75889c1fe9289a92dea9124a439 Mon Sep 17 00:00:00 2001
From: Pavel Fedin
Date: Fri, 25 Sep 2015 17:00:29 +0300
Subject: KVM: arm/arm64: Do not inject spurious interrupts
When lowering a level-triggered line from userspace, we forgot to lower
the pending bit on the emulated CPU interface and we also did not
re-compute the pending_on_cpu bitmap for the CPU affected by the change.
Update vgic_update_irq_pending() to fix the two issues above and also
raise a warning in vgic_quue_irq_to_lr if we encounter an interrupt
pending on a CPU which is neither marked active nor pending.
[ Commit text reworked completely - Christoffer ]
Signed-off-by: Pavel Fedin
Signed-off-by: Christoffer Dall
---
virt/kvm/arm/vgic.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
(limited to 'virt/kvm/arm')
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 6bd1c9b..596455a 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -1132,7 +1132,8 @@ static void vgic_queue_irq_to_lr(struct kvm_vcpu *vcpu, int irq,
kvm_debug("Set active, clear distributor: 0x%x\n", vlr.state);
vgic_irq_clear_active(vcpu, irq);
vgic_update_state(vcpu->kvm);
- } else if (vgic_dist_irq_is_pending(vcpu, irq)) {
+ } else {
+ WARN_ON(!vgic_dist_irq_is_pending(vcpu, irq));
vlr.state |= LR_STATE_PENDING;
kvm_debug("Set pending: 0x%x\n", vlr.state);
}
@@ -1607,8 +1608,12 @@ static int vgic_update_irq_pending(struct kvm *kvm, int cpuid,
} else {
if (level_triggered) {
vgic_dist_irq_clear_level(vcpu, irq_num);
- if (!vgic_dist_irq_soft_pend(vcpu, irq_num))
+ if (!vgic_dist_irq_soft_pend(vcpu, irq_num)) {
vgic_dist_irq_clear_pending(vcpu, irq_num);
+ vgic_cpu_irq_clear(vcpu, irq_num);
+ if (!compute_pending_for_cpu(vcpu))
+ clear_bit(cpuid, dist->irq_pending_on_cpu);
+ }
}
ret = false;
--
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