[Bridge] [PATCH net-next] bridge: skip fdb add if the port shouldn't learn

[David Miller]

From: Nikolay Aleksandrov <nikolay at cumulusnetworks.com>
Date: Thu, 21 May 2015 03:42:57 -0700

> From: Wilson Kok <wkok at cumulusnetworks.com>
> 
> Check in fdb_add_entry() if the source port should learn, similar
> check is used in br_fdb_update.
> Note that new fdb entries which are added manually or
> as local ones are still permitted.
> This patch has been tested by running traffic via a bridge port and
> switching the port's state, also by manually adding/removing entries
> from the bridge's fdb.
> 
> Signed-off-by: Wilson Kok <wkok at cumulusnetworks.com>
> Signed-off-by: Nikolay Aleksandrov <nikolay at cumulusnetworks.com>
> ---
> Nik: Maybe it'd be better if we returned an error even though it
>      doesn't look necessary. I'm open to suggestions.

If you don't return an error, then rtnetlink.c is going to emit a
NEWNEIGH netlink message.  I seriously doubt we want that to happen.