KVM: switch irq injection/acking data structures to irq_lock
Protect irq injection/acking data structures with a separate irq_lock
mutex. This fixes the following deadlock:
CPU A CPU B
kvm_vm_ioctl_deassign_dev_irq()
mutex_lock(&kvm->lock); worker_thread()
-> kvm_deassign_irq() -> kvm_assigned_dev_interrupt_work_handler()
-> deassign_host_irq() mutex_lock(&kvm->lock);
-> cancel_work_sync() [blocked]
[gleb: fix ia64 path]
Reported-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index a23f42e..44f20cd 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -424,7 +424,9 @@
trigger_mode = IOAPIC_LEVEL_TRIG;
else
trigger_mode = IOAPIC_EDGE_TRIG;
+ mutex_lock(&apic->vcpu->kvm->irq_lock);
kvm_ioapic_update_eoi(apic->vcpu->kvm, vector, trigger_mode);
+ mutex_unlock(&apic->vcpu->kvm->irq_lock);
}
static void apic_send_ipi(struct kvm_lapic *apic)
@@ -448,7 +450,9 @@
irq.trig_mode, irq.level, irq.dest_mode, irq.delivery_mode,
irq.vector);
+ mutex_lock(&apic->vcpu->kvm->irq_lock);
kvm_irq_delivery_to_apic(apic->vcpu->kvm, apic, &irq);
+ mutex_unlock(&apic->vcpu->kvm->irq_lock);
}
static u32 apic_get_tmcct(struct kvm_lapic *apic)