Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <5dbfa404-ec02-ac41-8c9b-55f8dfb7800a@nbd.name>
Date:   Tue, 8 Nov 2022 11:24:51 +0100
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0)
 Gecko/20100101 Thunderbird/102.3.2
Content-Language: en-US
To:     Vladimir Oltean <olteanv@gmail.com>
Cc:     netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, linux-kernel@vger.kernel.org
References: <20221107185452.90711-1-nbd@nbd.name>
 <20221107185452.90711-8-nbd@nbd.name> <20221107215745.ascdvnxqrbw4meuv@skbuf>
 <3b275dda-39ac-282d-8a46-d3a95fdfc766@nbd.name>
 <20221108090039.imamht5iyh2bbbnl@skbuf>
 <0948d841-b0eb-8281-455a-92f44586e0c0@nbd.name>
 <20221108094018.6cspe3mkh3hakxpd@skbuf>
 <a9109da1-ba49-d8f4-1315-278e5c890b99@nbd.name>
 <20221108100851.tl5aqhmbc5altdwv@skbuf>
From:   Felix Fietkau <nbd@nbd.name>
Subject: Re: [PATCH 08/14] net: vlan: remove invalid VLAN protocol warning
In-Reply-To: <20221108100851.tl5aqhmbc5altdwv@skbuf>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 08.11.22 11:08, Vladimir Oltean wrote:
> On Tue, Nov 08, 2022 at 10:46:54AM +0100, Felix Fietkau wrote:
>> I think it depends on the hardware. If you can rely on the hardware always
>> reporting the port out-of-band, a generic "oob" tagger would be fine.
>> In my case, it depends on whether a second non-DSA ethernet MAC is active on
>> the same device, so I do need to continue using the "mtk" tag driver.
> 
> It's not only about the time dimension (always OOB, vs sometimes OOB),
> but also about what is conveyed through the OOB tag. I can see 2 vendors
> agreeing today on a common "oob" tagger only to diverge in the future
> when they'll need to convey more information than just port id. What do
> you do with the tagging protocol string names then. Gotta make them
> unique from the get go, can't export "oob" to user space IMO.
> 
>> The flow dissector part is already solved: I simply used the existing
>> .flow_dissect() tag op.
> 
> Yes, well this seems like a generic enough case (DSA offload tag present
> => don't shift network header because it's where it should be) to treat
> it in the generic flow dissector and not have to invoke any tagger-specific
> fixup method.
In that case I think we shouldn't use METADATA_HW_PORT_MUX, since it is 
already used for other purposes. I will add a new metadata type 
METADATA_DSA instead.

- Felix