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

[Joseph Huang <joseph.huang.2024@gmail.com>]

On 4/4/2025 4:04 PM, Nikolay Aleksandrov wrote:
> 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!

Thanks for the review!

And a logistic question. Now that part 1 and part 2 are ack'd (thanks 
again for the review), when I send out v3, should I resend those 
(unmodified part 1 and part 2) with my v3 patch series, or should I 
break this one off and only send part 3 v3 as a separate patch?

Thanks,
Joseph