[PATCH NET-PREV 28/51] dsa: Use __register_netdevice()

From: Kirill Tkhai
Date: Sat Mar 22 2025 - 10:46:14 EST


Inherit nd_lock from conduit during registration
of a new device.

Signed-off-by: Kirill Tkhai <tkhai@xxxxx>
---
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);