Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 85428ac7 authored by Marcelo Tosatti's avatar Marcelo Tosatti Committed by Avi Kivity
Browse files

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: default avatarMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent 8ceed347

arch/x86/kvm/i8259.c

+11 −5
Original line number Diff line number Diff line
@@ -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;