KVM: arm/arm64: VGIC/ITS: Promote irq_lock() in update_affinity

Apparently the development of update_affinity() overlapped with the
promotion of irq_lock to be _irqsave, so the patch didn't convert this
lock over. This will make lockdep complain.

Fix this by disabling IRQs around the lock.

Cc: stable@vger.kernel.org
Fixes: 08c9fd0 ("KVM: arm/arm64: vITS: Add a helper to update the affinity of an LPI")
Reported-by: Jan Glauber <jan.glauber@caviumnetworks.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

virt/kvm/arm/vgic/vgic-its.c

@@ -350,10 +350,11 @@ static int vgic_copy_lpi_list(struct kvm_vcpu *vcpu, u32 **intid_ptr)
 static int update_affinity(struct vgic_irq *irq, struct kvm_vcpu *vcpu)
 {
 	int ret = 0;
+	unsigned long flags;
 
-	spin_lock(&irq->irq_lock);
+	spin_lock_irqsave(&irq->irq_lock, flags);
 	irq->target_vcpu = vcpu;
-	spin_unlock(&irq->irq_lock);
+	spin_unlock_irqrestore(&irq->irq_lock, flags);
 
 	if (irq->hw) {
 		struct its_vlpi_map map;