---

yaml
---
r: 362173
b: refs/heads/master
c: 33c83cb
h: refs/heads/master
i:
  362171: 6154d83
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 75da01e127f7db3b23effa6118336d303e7572a7
+refs/heads/master: 33c83cb3c1d84b76c8270abe5487e77f83a81b22

trunk/arch/arm/kvm/vgic.c

@@ -1016,21 +1016,6 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu)
 
 	kvm_debug("MISR = %08x\n", vgic_cpu->vgic_misr);
 
-	/*
-	 * We do not need to take the distributor lock here, since the only
-	 * action we perform is clearing the irq_active_bit for an EOIed
-	 * level interrupt.  There is a potential race with
-	 * the queuing of an interrupt in __kvm_vgic_flush_hwstate(), where we
-	 * check if the interrupt is already active. Two possibilities:
-	 *
-	 * - The queuing is occurring on the same vcpu: cannot happen,
-	 *   as we're already in the context of this vcpu, and
-	 *   executing the handler
-	 * - The interrupt has been migrated to another vcpu, and we
-	 *   ignore this interrupt for this run. Big deal. It is still
-	 *   pending though, and will get considered when this vcpu
-	 *   exits.
-	 */
 	if (vgic_cpu->vgic_misr & GICH_MISR_EOI) {
 		/*
 		 * Some level interrupts have been EOIed. Clear their
@@ -1069,9 +1054,8 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu)
 }
 
 /*
- * Sync back the VGIC state after a guest run. We do not really touch
- * the distributor here (the irq_pending_on_cpu bit is safe to set),
- * so there is no need for taking its lock.
+ * Sync back the VGIC state after a guest run. The distributor lock is
+ * needed so we don't get preempted in the middle of the state processing.
  */
 static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
 {
@@ -1117,10 +1101,14 @@ void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
 
 void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
 {
+	struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
 	if (!irqchip_in_kernel(vcpu->kvm))
 		return;
 
+	spin_lock(&dist->lock);
 	__kvm_vgic_sync_hwstate(vcpu);
+	spin_unlock(&dist->lock);
 }
 
 int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)