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Diffstat (limited to 'arch/x86/kvm/i8259.c')
-rw-r--r--arch/x86/kvm/i8259.c44
1 files changed, 25 insertions, 19 deletions
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index 01f15168280..d057c0cbd24 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -38,7 +38,15 @@ static void pic_clear_isr(struct kvm_kpic_state *s, int irq)
s->isr_ack |= (1 << irq);
if (s != &s->pics_state->pics[0])
irq += 8;
+ /*
+ * We are dropping lock while calling ack notifiers since ack
+ * notifier callbacks for assigned devices call into PIC recursively.
+ * Other interrupt may be delivered to PIC while lock is dropped but
+ * it should be safe since PIC state is already updated at this stage.
+ */
+ spin_unlock(&s->pics_state->lock);
kvm_notify_acked_irq(s->pics_state->kvm, SELECT_PIC(irq), irq);
+ spin_lock(&s->pics_state->lock);
}
void kvm_pic_clear_isr_ack(struct kvm *kvm)
@@ -176,16 +184,18 @@ int kvm_pic_set_irq(void *opaque, int irq, int level)
static inline void pic_intack(struct kvm_kpic_state *s, int irq)
{
s->isr |= 1 << irq;
- if (s->auto_eoi) {
- if (s->rotate_on_auto_eoi)
- s->priority_add = (irq + 1) & 7;
- pic_clear_isr(s, irq);
- }
/*
* We don't clear a level sensitive interrupt here
*/
if (!(s->elcr & (1 << irq)))
s->irr &= ~(1 << irq);
+
+ if (s->auto_eoi) {
+ if (s->rotate_on_auto_eoi)
+ s->priority_add = (irq + 1) & 7;
+ pic_clear_isr(s, irq);
+ }
+
}
int kvm_pic_read_irq(struct kvm *kvm)
@@ -225,22 +235,11 @@ int kvm_pic_read_irq(struct kvm *kvm)
void kvm_pic_reset(struct kvm_kpic_state *s)
{
- int irq, irqbase, n;
+ int irq;
struct kvm *kvm = s->pics_state->irq_request_opaque;
struct kvm_vcpu *vcpu0 = kvm->bsp_vcpu;
+ u8 irr = s->irr, isr = s->imr;
- 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)) {
- n = irq + irqbase;
- kvm_notify_acked_irq(kvm, SELECT_PIC(n), n);
- }
- }
s->last_irr = 0;
s->irr = 0;
s->imr = 0;
@@ -256,6 +255,13 @@ void kvm_pic_reset(struct kvm_kpic_state *s)
s->rotate_on_auto_eoi = 0;
s->special_fully_nested_mode = 0;
s->init4 = 0;
+
+ for (irq = 0; irq < PIC_NUM_PINS/2; irq++) {
+ if (vcpu0 && kvm_apic_accept_pic_intr(vcpu0))
+ if (irr & (1 << irq) || isr & (1 << irq)) {
+ pic_clear_isr(s, irq);
+ }
+ }
}
static void pic_ioport_write(void *opaque, u32 addr, u32 val)
@@ -298,9 +304,9 @@ static void pic_ioport_write(void *opaque, u32 addr, u32 val)
priority = get_priority(s, s->isr);
if (priority != 8) {
irq = (priority + s->priority_add) & 7;
- pic_clear_isr(s, irq);
if (cmd == 5)
s->priority_add = (irq + 1) & 7;
+ pic_clear_isr(s, irq);
pic_update_irq(s->pics_state);
}
break;