[bug report] net: dsa: allow masters to join a LAG

[Dan Carpenter <dan.carpenter@xxxxxxxxxx>]

Hello Vladimir Oltean,

The patch acc43b7bf52a: "net: dsa: allow masters to join a LAG" from
Sep 11, 2022, leads to the following Smatch static checker warning:

	net/dsa/slave.c:3165 dsa_slave_netdevice_event()
	error: uninitialized symbol 'err'.

net/dsa/slave.c
    3145         case NETDEV_CHANGELOWERSTATE: {
    3146                 struct netdev_notifier_changelowerstate_info *info = ptr;
    3147                 struct dsa_port *dp;
    3148                 int err;
    3149 
    3150                 if (dsa_slave_dev_check(dev)) {
    3151                         dp = dsa_slave_to_port(dev);
    3152 
    3153                         err = dsa_port_lag_change(dp, info->lower_state_info);
    3154                 }
    3155 
    3156                 /* Mirror LAG port events on DSA masters that are in
    3157                  * a LAG towards their respective switch CPU ports
    3158                  */
    3159                 if (netdev_uses_dsa(dev)) {
    3160                         dp = dev->dsa_ptr;
    3161 
    3162                         err = dsa_port_lag_change(dp, info->lower_state_info);
    3163                 }

Can both dsa_slave_dev_check() and netdev_uses_dsa() be false?

    3164 
--> 3165                 return notifier_from_errno(err);
    3166         }
    3167         case NETDEV_CHANGE:
    3168         case NETDEV_UP: {

regards,
dan carpenter