vlan: Propagate NETDEV_NOTIFY_PEERS notifier

The NETDEV_NOTIFY_PEERS notifier indicates that a device moved to a

different physical link; this also applies to any VLAN devices on top
of it.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/8021q/vlan.c

@@ -499,6 +499,17 @@ 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;
+
+	case NETDEV_NOTIFY_PEERS:
+		/* Propagate to vlan devices */
+		for (i = 0; i < VLAN_N_VID; i++) {
+			vlandev = vlan_group_get_device(grp, i);
+			if (!vlandev)
+				continue;
+
+			call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, vlandev);
+		}
+		break;
 	}
 
 out: