Re: [PATCH] net: dsa: mv88e6xxx: avoid error message on remove from VLAN 0

From: Vivien Didelot
Date: Fri May 31 2019 - 14:23:00 EST


Hi Florian,

On Fri, 31 May 2019 09:36:13 -0700, Florian Fainelli <f.fainelli@xxxxxxxxx> wrote:
> > But VID 0 has a special meaning for the kernel, it means the port's private
> > database (when it is isolated, non-bridged), it is not meant to be programmed
> > in the switch. That's why I would've put that knowledge into the DSA layer,
> > which job is to translate the kernel operations to the (dumb) DSA drivers.
> >
> > I hope I'm seeing things correctly here.
>
> Your first part about the fact that it's the port private database is
> true, the fact that it is not programmed into the HW actually depends on
> what the switch is capable of doing. With mv88e6xxx you have per-port
> VLAN filtering controls, but other switches that do not have that
> capability need to program VID == 0 into the HW to continue maintaining
> VLAN filtering on a non bridged port while a bridge has enslaved other
> ports of the switch.

Are you saying that switches without per-port VLAN filtering controls
will program VID 0, and thus put all non bridged ports into the same VLAN,
allowing them to talk to each other?


Thanks,
Vivien