Re: [Patch v2 net-next 3/3] net: bridge: mcast: Notify on mdb offload failure

[Nikolay Aleksandrov <razor@blackwall.org>]

On 4/4/25 18:25, Joseph Huang wrote:
> On 4/4/2025 6:29 AM, Nikolay Aleksandrov wrote:
>> On 4/4/25 02:44, Joseph Huang wrote:
>>> Notify user space on mdb offload failure if mdb_offload_fail_notification
>>> is set.
>>>
>>> Signed-off-by: Joseph Huang <Joseph.Huang@garmin.com>
>>> ---
>>>   net/bridge/br_mdb.c       | 26 +++++++++++++++++++++-----
>>>   net/bridge/br_private.h   |  9 +++++++++
>>>   net/bridge/br_switchdev.c |  4 ++++
>>>   3 files changed, 34 insertions(+), 5 deletions(-)
>>>
>>
>> The patch looks good, but one question - it seems we'll mark mdb entries with
>> "offload failed" when we get -EOPNOTSUPP as an error as well. Is that intended?
>>
>> That is, if the option is enabled and we have mixed bridge ports, we'll mark mdbs
>> to the non-switch ports as offload failed, but it is not due to a switch offload
>> error.
> 
> Good catch. No, that was not intended.
> 
> What if we short-circuit and just return like you'd suggested initially if err == -EOPNOTSUPP?
> 
>>> diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
>>> index 40f0b16e4df8..9b5005d0742a 100644
>>> --- a/net/bridge/br_switchdev.c
>>> +++ b/net/bridge/br_switchdev.c
>>> @@ -504,6 +504,7 @@ static void br_switchdev_mdb_complete(struct net_device *dev, int err, void *pri
>>>       struct net_bridge_mdb_entry *mp;
>>>       struct net_bridge_port *port = data->port;
>>>       struct net_bridge *br = port->br;
>>> +    u8 old_flags;
>>>   
> 
> +    if (err == -EOPNOTSUPP)
> +        goto notsupp;
> 
>>>       spin_lock_bh(&br->multicast_lock);
>>>       mp = br_mdb_ip_get(br, &data->ip);
>>> @@ -514,7 +515,10 @@ static void br_switchdev_mdb_complete(struct net_device *dev, int err, void *pri
>>>           if (p->key.port != port)
>>>               continue;
>>>   +        old_flags = p->flags;
>>>           br_multicast_set_pg_offload_flags(p, !err);
>>> +        if (br_mdb_should_notify(br, old_flags ^ p->flags))
>>> +            br_mdb_flag_change_notify(br->dev, mp, p);
>>>       }
>>>   out:
>>>       spin_unlock_bh(&br->multicast_lock);
>>
> 
> + notsupp:
>     kfree(priv);

Looks good to me. Thanks!