net: Fix bridge enslavement failure

When a netdev is enslaved to a bridge, its parent identifier is queried.
This is done so that packets that were already forwarded in hardware
will not be forwarded again by the bridge device between netdevs
belonging to the same hardware instance.

The operation fails when the netdev is an upper of netdevs with
different parent identifiers.

Instead of failing the enslavement, have dev_get_port_parent_id() return
'-EOPNOTSUPP' which will signal the bridge to skip the query operation.
Other callers of the function are not affected by this change.

Fixes: 7e1146e8c10c ("net: devlink: introduce devlink_compat_switch_id_get() helper")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reported-by: Vasundhara Volam <vasundhara-v.volam@broadcom.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/dev.c b/net/core/dev.c
index 4086d335978c1bf62bd3965bd2ea96a4ac06b13d..266073e300b5fc21440ea8f8ffc9306a1fc9f370 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -8647,7 +8647,7 @@ int dev_get_port_parent_id(struct net_device *dev,
                if (!first.id_len)
                        first = *ppid;
                else if (memcmp(&first, ppid, sizeof(*ppid)))
-                       return -ENODATA;
+                       return -EOPNOTSUPP;
        }
 
        return err;