Re: [RFC net-next 3/3] net: dsa: tag_qca: set offload_fwd_mark

From: Vladimir Oltean
Date: Sun Aug 08 2021 - 17:19:13 EST


On Mon, Aug 09, 2021 at 12:12:24AM +0800, DENG Qingfang wrote:
> On Sun, Aug 08, 2021 at 01:57:21AM +0300, Vladimir Oltean wrote:
> > In this day and age, I consider this commit to be a bug fix, since the
> > software bridge, seeing an skb with offload_fwd_mark = false on an
> > offloaded port, will think it hasn't been forwarded and do that job
> > itself. So all broadcast and multicast traffic flooded to the CPU will
> > end up being transmitted with duplicates on the other bridge ports.
> >
> > When the qca8k tagger was added in 2016 in commit cafdc45c949b
> > ("net-next: dsa: add Qualcomm tag RX/TX handler"), the offload_fwd_mark
> > framework was already there, but no DSA driver was using it - the first
> > commit I can find that uses offload_fwd_mark in DSA is f849772915e5
> > ("net: dsa: lan9303: lan9303_rcv set skb->offload_fwd_mark") in 2017,
> > and then quite a few more followed suit. But you could still blame
> > commit cafdc45c949b.
>
> The driver currently only enables flooding to the CPU port (like MT7530
> back then), so offload_fwd_mark should NOT be set until bridge flags
> offload is supported.

Ok, I missed that. Please squash this with patch 1 then, please.