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

Signed-off-by: Kirill Tkhai <tkhai@ya.ru>
---
 drivers/net/usb/qmi_wwan.c |   14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c
index 4823dbdf5465..beec69580978 100644
--- a/drivers/net/usb/qmi_wwan.c
+++ b/drivers/net/usb/qmi_wwan.c
@@ -246,6 +246,7 @@ static int qmimux_register_device(struct net_device *real_dev, u8 mux_id)
 {
 	struct net_device *new_dev;
 	struct qmimux_priv *priv;
+	struct nd_lock *nd_lock;
 	int err;
 
 	new_dev = alloc_netdev(sizeof(struct qmimux_priv),
@@ -260,14 +261,23 @@ static int qmimux_register_device(struct net_device *real_dev, u8 mux_id)
 
 	new_dev->sysfs_groups[0] = &qmi_wwan_sysfs_qmimux_attr_group;
 
-	err = register_netdevice(new_dev);
-	if (err < 0)
+	err = -ENOMEM;
+
+	lock_netdev(real_dev, &nd_lock);
+	attach_nd_lock(new_dev, nd_lock);
+	err = __register_netdevice(new_dev);
+	if (err < 0) {
+		detach_nd_lock(new_dev);
+		unlock_netdev(nd_lock);
 		goto out_free_newdev;
+	}
 
 	/* Account for reference in struct qmimux_priv_priv */
 	dev_hold(real_dev);
 
 	err = netdev_upper_dev_link(real_dev, new_dev, NULL);
+	unlock_netdev(nd_lock);
+
 	if (err)
 		goto out_unregister_netdev;