Inherit nd_lock from conduit during registration
of a new device.

Signed-off-by: Kirill Tkhai <tkhai@ya.ru>
---
 net/dsa/user.c |   25 +++++++++++++++----------
 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/net/dsa/user.c b/net/dsa/user.c
index f5adfa1d978a..cc3e0006f953 100644
--- a/net/dsa/user.c
+++ b/net/dsa/user.c
@@ -2686,6 +2686,7 @@ int dsa_user_create(struct dsa_port *port)
 	struct net_device *conduit = dsa_port_to_conduit(port);
 	struct dsa_switch *ds = port->ds;
 	struct net_device *user_dev;
+	struct nd_lock *nd_lock;
 	struct dsa_user_priv *p;
 	const char *name;
 	int assign_type;
@@ -2759,38 +2760,42 @@ int dsa_user_create(struct dsa_port *port)
 		dev_warn(ds->dev, "nonfatal error %d setting MTU to %d on port %d\n",
 			 ret, ETH_DATA_LEN, port->index);
 
-	ret = register_netdevice(user_dev);
+	lock_netdev(conduit, &nd_lock);
+	attach_nd_lock(user_dev, nd_lock);
+	ret = __register_netdevice(user_dev);
 	if (ret) {
 		netdev_err(conduit, "error %d registering interface %s\n",
 			   ret, user_dev->name);
-		rtnl_unlock();
+		detach_nd_lock(user_dev);
+		unlock_netdev(nd_lock);
 		goto out_phy;
 	}
 
+	ret = netdev_upper_dev_link(conduit, user_dev, NULL);
+	unlock_netdev(nd_lock);
+
+	if (ret)
+		goto out_unregister;
+
 	if (IS_ENABLED(CONFIG_DCB)) {
 		ret = dsa_user_dcbnl_init(user_dev);
 		if (ret) {
 			netdev_err(user_dev,
 				   "failed to initialize DCB: %pe\n",
 				   ERR_PTR(ret));
-			rtnl_unlock();
 			goto out_unregister;
 		}
 	}
 
-	ret = netdev_upper_dev_link(conduit, user_dev, NULL);
-
 	rtnl_unlock();
 
-	if (ret)
-		goto out_unregister;
-
 	return 0;
 
 out_unregister:
-	unregister_netdev(user_dev);
+	lock_netdev(user_dev, &nd_lock);
+	__unregister_netdevice(user_dev);
+	unlock_netdev(nd_lock);
 out_phy:
-	rtnl_lock();
 	phylink_disconnect_phy(p->dp->pl);
 	rtnl_unlock();
 	dsa_port_phylink_destroy(p->dp);