Re: [PATCH net-next v2 4/4] net: dsa: mt7530: always install FDB entries with IVL and FID 1

From: Vladimir Oltean
Date: Tue Aug 03 2021 - 14:23:41 EST

On Wed, Aug 04, 2021 at 01:53:54AM +0800, DENG Qingfang wrote:
> On Tue, Aug 03, 2021 at 07:51:38PM +0300, Vladimir Oltean wrote:
> >
> > The way FDB entries are installed now makes a lot more intuitive sense.
> Did you forget to add the Reviewed-by tag?

Yeah, in fact I did. I was in a rush and by the time I figured that
I didn't do that, I had already left home.

Still, in fact the patch is obviously correct, which is nice. Standalone
ports never learn and the FDB lookup will always miss because it's in
FID 0 (a separate FID compared to the bridge ports) and there is no FDB
entry there. Packets will always be flooded to their only possible
destination, the CPU port. Ports under VLAN-unaware bridges always use
IVL and learn using the pvid, which is zero, and which happily coincides
with the VID which the bridge uses to install VLAN-unaware FDB entries.
Ports under VLAN-aware bridges again use IVL but the VID is taken from
the packet not just from the pvid, so the VID will be >= 1 there. Again
it coincides with the vid that the bridge uses to offload FDB entries.
Nice, I really like it, it is really simple.

Reviewed-by: Vladimir Oltean <olteanv@xxxxxxxxx>