Date:   Mon, 30 Jan 2023 15:01:19 +0200
From:   Vladimir Oltean <olteanv@gmail.com>
To:     Frank Wunderlich <frank-w@public-files.de>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        Florian Fainelli <f.fainelli@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Landen Chao <Landen.Chao@mediatek.com>,
        Sean Wang <sean.wang@mediatek.com>,
        DENG Qingfang <dqfext@gmail.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Daniel Golle <daniel@makrotopia.org>
Subject: Re: [BUG] vlan-aware bridge breaks vlan on another port on same gmac
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On Sat, Jan 21, 2023 at 03:35:28PM +0100, Frank Wunderlich wrote:
> btw. why is my vlan software-only and not pushed to hardware?

Short story, because committing it to hardware is a useless complication.
A standalone port should be VLAN-unaware, or i.o.w. it should not drop
based on VLAN port membership, shouldn't add or strip any VLAN header,
and should forward as if the VLAN wasn't there.

So the behavior of a standalone port is absolutely sufficient as a basis
for an 8021q upper interface to see the traffic it needs, and for the
traffic it sends to reach the outside world as it intended.