Re: [PATCH net v2] net: dsa: tag_brcm: legacy: fix untagged rx on unbridged ports for bcm63xx

[Florian Fainelli <florian.fainelli@broadcom.com>]

On 10/29/25 18:12, Jakub Kicinski wrote:
> On Tue, 28 Oct 2025 11:15:23 +0100 Jonas Gorski wrote:
>>> Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
>>>
>>> Sorry for dropping the ball on v1. To reply to your reply there,
>>> https://lore.kernel.org/netdev/CAOiHx=mNnMJTnAN35D6=LPYVTQB+oEmedwqrkA6VRLRVi13Kjw@mail.gmail.com/
>>> I hadn't realized that b53 sets ds->untag_bridge_pvid conditionally,
>>> which makes any consolidation work in stable trees very complicated
>>> (although still desirable in net-next).
>>
>> It's for some more obscure cases where we cannot use the Broadcom tag,
>> like a switch where the CPU port isn't a management port but a normal
>> port. I am not sure this really exists, but maybe Florian knows if
>> there are any (still used) boards where this applies.

There are two devices that I encountered where we could not use Broadcom 
tags. One was indeed a case where the CPU port was for reasons unknown 
not the IMP port, and therefore it was not possible to use Broadcom 
tags. This system is not supported anymore and won't be. The second 
device was an external BCM53125 connected to an internal SF2 switch, in 
that case, we cannot enable Broadcom tags on the BCM53125 because there 
is no way to way to cascade both tags one after the other on ingress 
unfortunately...

>>
>> If not, I am more than happy to reject this path as -EINVAL instead of
>> the current TAG_NONE with untag_bridge_pvid = true.
> 
> IIUC Vladimir is okay with the patch but I realized now that Florian
> is not even CCed here, and ack would be good. Adding him now. And we
> should probably add a MAINTAINERS entry for tag_brcm to avoid this in
> the future?

Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
-- 
Florian