Re: [RFC PATCH net-next 10/16] mlxsw: spectrum_switchdev: Add support for locked FDB notifications

[Vladimir Oltean <vladimir.oltean@nxp.com>]

Hi Ido,

On Mon, Oct 31, 2022 at 10:32:10AM +0200, Vladimir Oltean wrote:
> On Sun, Oct 30, 2022 at 10:23:07AM +0200, Ido Schimmel wrote:
> > Right. I'm quite reluctant to add the MAB flag to
> > BR_PORT_FLAGS_HW_OFFLOAD as part of this patchset for the simple reason
> > that it is not really needed. I'm not worried about someone adding it
> > later when it is actually needed. We will probably catch the omission
> > during code review. Worst case, we have a selftest that will break,
> > notifying us that a bug fix is needed.
> 
> For drivers which don't emit SWITCHDEV_FDB_ADD_TO_BRIDGE but do offload
> BR_PORT_LOCKED (like mv88e6xxx), things will not work correctly on day 1
> of BR_PORT_MAB because they are not told MAB is enabled, so they have no
> way of rejecting it until things work properly with the offload in place.
> 
> It's the same reason for which we have BR_HAIRPIN_MODE | BR_ISOLATED |
> BR_MULTICAST_TO_UNICAST in BR_PORT_FLAGS_HW_OFFLOAD, even if nobody acts
> upon them.

Do you have any comment on this? You resent the BR_PORT_MAB patches
without even an ack that yes, mv88e6xxx will not support MAB being
enabled on a bridge port, and will not reject the configuration either,
and that's ok/intended.

Do you think this is not true? Irrelevant? The "fix" (to implement offloading)
might come in this development cycle, or it might not.