From 85428ac7c39ab5fff23b5d14ccb32941e9401285 Mon Sep 17 00:00:00 2001
From: Marcelo Tosatti <mtosatti@redhat.com>
Date: Thu, 14 Aug 2008 20:53:25 -0300
Subject: KVM: fix i8259 reset irq acking
The irq ack during pic reset has three problems:
- Ignores slave/master PIC, using gsi 0-8 for both.
- Generates an ACK even if the APIC is in control.
- Depends upon IMR being clear, which is broken if the irq was masked
at the time it was generated.
The last one causes the BIOS to hang after the first reboot of
Windows installation, since PIT interrupts stop.
[avi: fix check whether pic interrupts are seen by cpu]
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
---
arch/x86/kvm/i8259.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)
(limited to 'arch/x86/kvm/i8259.c')
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index de704995b81..71e3eeeccae 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -195,13 +195,19 @@ int kvm_pic_read_irq(struct kvm *kvm)
void kvm_pic_reset(struct kvm_kpic_state *s)
{
- int irq;
+ int irq, irqbase;
struct kvm *kvm = s->pics_state->irq_request_opaque;
+ struct kvm_vcpu *vcpu0 = kvm->vcpus[0];
- for (irq = 0; irq < PIC_NUM_PINS; irq++) {
- if (!(s->imr & (1 << irq)) && (s->irr & (1 << irq) ||
- s->isr & (1 << irq)))
- kvm_notify_acked_irq(kvm, irq);
+ if (s == &s->pics_state->pics[0])
+ irqbase = 0;
+ else
+ irqbase = 8;
+
+ for (irq = 0; irq < PIC_NUM_PINS/2; irq++) {
+ if (vcpu0 && kvm_apic_accept_pic_intr(vcpu0))
+ if (s->irr & (1 << irq) || s->isr & (1 << irq))
+ kvm_notify_acked_irq(kvm, irq+irqbase);
}
s->last_irr = 0;
s->irr = 0;
--
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