The objective is to conform .newlink with its callers,
which already assign nd_lock (and matches master nd_lock
if there is one).

Also, use __unregister_netdevice() since we know
there is held lock in that path.

Signed-off-by: Kirill Tkhai <tkhai@ya.ru>
---
 net/8021q/vlan.c |   11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c
index e45187b88220..ca3ba251a145 100644
--- a/net/8021q/vlan.c
+++ b/net/8021q/vlan.c
@@ -176,7 +176,7 @@ int register_vlan_dev(struct net_device *dev, struct netlink_ext_ack *extack)
 	if (err < 0)
 		goto out_uninit_mvrp;
 
-	err = register_netdevice(dev);
+	err = __register_netdevice(dev);
 	if (err < 0)
 		goto out_uninit_mvrp;
 
@@ -196,7 +196,7 @@ int register_vlan_dev(struct net_device *dev, struct netlink_ext_ack *extack)
 	return 0;
 
 out_unregister_netdev:
-	unregister_netdevice(dev);
+	__unregister_netdevice(dev);
 out_uninit_mvrp:
 	if (grp->nr_vlan_devs == 0)
 		vlan_mvrp_uninit_applicant(real_dev);
@@ -217,6 +217,7 @@ static int register_vlan_device(struct net_device *real_dev, u16 vlan_id)
 	struct vlan_dev_priv *vlan;
 	struct net *net = dev_net(real_dev);
 	struct vlan_net *vn = net_generic(net, vlan_net_id);
+	struct nd_lock *nd_lock;
 	char name[IFNAMSIZ];
 	int err;
 
@@ -274,7 +275,13 @@ static int register_vlan_device(struct net_device *real_dev, u16 vlan_id)
 	vlan->flags = VLAN_FLAG_REORDER_HDR;
 
 	new_dev->rtnl_link_ops = &vlan_link_ops;
+
+	lock_netdev(real_dev, &nd_lock);
+	attach_nd_lock(new_dev, nd_lock);
 	err = register_vlan_dev(new_dev, NULL);
+	if (err)
+		detach_nd_lock(new_dev);
+	unlock_netdev(nd_lock);
 	if (err < 0)
 		goto out_free_newdev;