vlan: allow to change type when no vlan device is hooked on netdev

jpirko · davem330 · commit 18c22a03a218 · 2012-10-18T15:34:30.000-04:00
vlan_info might be present but still no vlan devices might be there.
That is in case of vlan0 automatically added.

So in that case, allow to change netdev type.

Reported-by: Jon Stanley &lt;jstanley@rmrf.net&gt;
Signed-off-by: Jiri Pirko &lt;jiri@resnulli.us&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c
@@ -463,7 +463,9 @@ static int vlan_device_event(struct notifier_block *unused, unsigned long event,
 
 	case NETDEV_PRE_TYPE_CHANGE:
 		/* Forbid underlaying device to change its type. */
-		return NOTIFY_BAD;
+		if (vlan_uses_dev(dev))
+			return NOTIFY_BAD;
+		break;
 
 	case NETDEV_NOTIFY_PEERS:
 	case NETDEV_BONDING_FAILOVER:
