diff mbox series

[v2,net-next,4/6] net: dsa: exit early in dsa_slave_switchdev_event if we can't program the FDB

Message ID 20201213024018.772586-5-vladimir.oltean@nxp.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series Offload software learnt bridge addresses to DSA | expand

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Commit Message

Vladimir Oltean Dec. 13, 2020, 2:40 a.m. UTC
Right now, the following would happen for a switch driver that does not
implement .port_fdb_add or .port_fdb_del.

dsa_slave_switchdev_event returns NOTIFY_OK and schedules:
-> dsa_slave_switchdev_event_work
   -> dsa_port_fdb_add
      -> dsa_port_notify(DSA_NOTIFIER_FDB_ADD)
         -> dsa_switch_fdb_add
            -> if (!ds->ops->port_fdb_add) return -EOPNOTSUPP;
   -> an error is printed with dev_dbg, and
      dsa_fdb_offload_notify(switchdev_work) is not called.

We can avoid scheduling the worker for nothing and say NOTIFY_OK.
Because we don't call dsa_fdb_offload_notify, the static FDB entry will
remain just in the software bridge.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
Changes in v2:
Patch is new.

 net/dsa/slave.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Florian Fainelli Dec. 13, 2020, 3:29 a.m. UTC | #1
On 12/12/2020 6:40 PM, Vladimir Oltean wrote:
> Right now, the following would happen for a switch driver that does not
> implement .port_fdb_add or .port_fdb_del.
> 
> dsa_slave_switchdev_event returns NOTIFY_OK and schedules:
> -> dsa_slave_switchdev_event_work
>    -> dsa_port_fdb_add
>       -> dsa_port_notify(DSA_NOTIFIER_FDB_ADD)
>          -> dsa_switch_fdb_add
>             -> if (!ds->ops->port_fdb_add) return -EOPNOTSUPP;
>    -> an error is printed with dev_dbg, and
>       dsa_fdb_offload_notify(switchdev_work) is not called.
> 
> We can avoid scheduling the worker for nothing and say NOTIFY_OK.

Not sure if this comment is intended to describe what is being added,
only if you have to respin, should this be NOTIFY_DONE?

> Because we don't call dsa_fdb_offload_notify, the static FDB entry will
> remain just in the software bridge.
> 
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
diff mbox series

Patch

diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 99907e76770b..53d9d2ea9369 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -2129,6 +2129,9 @@  static int dsa_slave_switchdev_event(struct notifier_block *unused,
 
 		dp = dsa_slave_to_port(dev);
 
+		if (!dp->ds->ops->port_fdb_add || !dp->ds->ops->port_fdb_del)
+			return NOTIFY_DONE;
+
 		switchdev_work = kzalloc(sizeof(*switchdev_work), GFP_ATOMIC);
 		if (!switchdev_work)
 			return NOTIFY_BAD;