KVM: fix race with level interrupts

[~andy/linux] / virt / kvm / ioapic.c

diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
index 26fd54dc459ec8900d83da38c9132878ee60780d..ef61d529a6c48b033cdca2dd249a3dbe8c6356ec 100644 (file)
--- a/virt/kvm/ioapic.c
+++ b/virt/kvm/ioapic.c
@@ -191,7 +191,8 @@ static int ioapic_deliver(struct kvm_ioapic *ioapic, int irq)
        return kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe);
 }
 
-int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
+int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int irq_source_id,
+                      int level)
 {
        u32 old_irr;
        u32 mask = 1 << irq;
@@ -201,9 +202,11 @@ int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
        spin_lock(&ioapic->lock);
        old_irr = ioapic->irr;
        if (irq >= 0 && irq < IOAPIC_NUM_PINS) {
+               int irq_level = __kvm_irq_line_state(&ioapic->irq_states[irq],
+                                                    irq_source_id, level);
                entry = ioapic->redirtbl[irq];
-               level ^= entry.fields.polarity;
-               if (!level)
+               irq_level ^= entry.fields.polarity;
+               if (!irq_level)
                        ioapic->irr &= ~mask;
                else {
                        int edge = (entry.fields.trig_mode == IOAPIC_EDGE_TRIG);
@@ -221,6 +224,16 @@ int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
        return ret;
 }
 
+void kvm_ioapic_clear_all(struct kvm_ioapic *ioapic, int irq_source_id)
+{
+       int i;
+
+       spin_lock(&ioapic->lock);
+       for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
+               __clear_bit(irq_source_id, &ioapic->irq_states[i]);
+       spin_unlock(&ioapic->lock);
+}
+
 static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int vector,
                                     int trigger_mode)
 {