Re: [PATCH net] net: dsa: fix VLAN 0 filter imbalance when toggling filtering

From: Vladimir Oltean
Date: Fri Apr 25 2025 - 03:52:08 EST


On Fri, Apr 25, 2025 at 09:30:17AM +0200, Jonas Gorski wrote:
> After looking into it a bit more, netdev_update_features() does not
> relay any success or failure, so there is no way for DSA to know if it
> succeded or not. And there are places where we temporarily want to
> undo all configured vlans, which makes it hard to do via
> netdev_update_features().
>
> Not sure anymore if this is a good way forward, especially if it is
> just meant to fix a corner case. @Vladimir, what do you think?
>
> I'd probably rather go forward with the current fix (+ apply it as
> well for the vlan core code), and do the conversion to
> netdev_update_features() at later time, since I see potential for
> unexpected breakage.
>
> Best regards,
> Jonas

I see the inconsistency you're trying to fix, but I'm still wondering
whether it is the fix that b53 requires, given the fact that it doesn't
seem to otherwise depend on 8021q to set up or modify VID 0. I would say
I don't yet have a fully developed opinion and I am waiting for you to
provide the result of the modified bridge_vlan_aware selftest,
specifically drop_untagged().