Re: [RFC net-next v2 4/4] Revert "mt7530 mt7530_fdb_write only set ivl bit vid larger than 1"

[Vladimir Oltean]

On Mon, Aug 02, 2021 at 11:48:38PM +0800, DENG Qingfang wrote:
> On Mon, Aug 02, 2021 at 04:44:09PM +0300, Vladimir Oltean wrote:
> > Would you mind explaining what made VID 1 special in Eric's patch in the
> > first place?
>
> The default value of all ports' PVID is 1, which is copied into the FDB
> entry, even if the ports are VLAN unaware. So running `bridge fdb show`
> will show entries like `dev sw0p0 vlan 1 self` even on a VLAN-unaware
> bridge.
>
> Eric probably thought VID 1 is the FDB of all VLAN-unaware bridges, but
> that is not true. And his patch probably cause a new issue that FDB is
> inaccessible in a VLAN-**aware** bridge with PVID 1.
>
> This series sets PVID to 0 on VLAN-unaware ports, so `bridge fdb show`
> will no longer print `vlan 1` on VLAN-unaware bridges, and we don't
> need special case in port_fdb_{add,del} for assisted learning.

All things seriously worth mentioning in the commit message.