linux-kernel - Re: [PATCH net-next 02/11] net: dsa: tag_rzn1_a5psw: Add RZ/T2H ETHSW tag protocol and register ethsw tag driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CA+V-a8vyjt43TPUmu+1TFHFvQsBwYTzKFSQOQm=O3R0dpZWG_w@mail.gmail.com>
Date: Fri, 21 Nov 2025 20:29:04 +0000
From: "Lad, Prabhakar" <prabhakar.csengg@...il.com>
To: Vladimir Oltean <olteanv@...il.com>
Cc: Clément Léger <clement.leger@...tlin.com>, 
	Andrew Lunn <andrew@...n.ch>, "David S. Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>, 
	Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>, Rob Herring <robh@...nel.org>, 
	Krzysztof Kozlowski <krzk+dt@...nel.org>, Conor Dooley <conor+dt@...nel.org>, 
	Simon Horman <horms@...nel.org>, Philipp Zabel <p.zabel@...gutronix.de>, 
	Russell King <linux@...linux.org.uk>, Geert Uytterhoeven <geert+renesas@...der.be>, 
	Magnus Damm <magnus.damm@...il.com>, linux-renesas-soc@...r.kernel.org, 
	netdev@...r.kernel.org, devicetree@...r.kernel.org, 
	linux-kernel@...r.kernel.org, Biju Das <biju.das.jz@...renesas.com>, 
	Fabrizio Castro <fabrizio.castro.jz@...esas.com>, 
	Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
Subject: Re: [PATCH net-next 02/11] net: dsa: tag_rzn1_a5psw: Add RZ/T2H ETHSW
 tag protocol and register ethsw tag driver

Hi Vladimir,

Thank you for the review.

On Fri, Nov 21, 2025 at 7:27 PM Vladimir Oltean <olteanv@...il.com> wrote:
>
> On Fri, Nov 21, 2025 at 11:35:28AM +0000, Prabhakar wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
> >
> > Add an explicit tag protocol for the RZ/T2H ETHSW and register a separate
> > ethsw tag driver so the existing A5PSW tag implementation can be reused
> > for RZ/T2H without code duplication.
> >
> > The ETHSW IP on RZ/T2H shares substantial commonality with the A5PSW IP on
> > RZ/N1, and the current tag driver does not touch the register fields that
> > differ between the two blocks.
>
> Tagging protocol drivers are specifically written to not deal with
> register fields. I would like a clarification that this is a phrasing
> mistake and you mean the packet header fields that differ between the
> ETHSW and the A5PSW tag format.
>
Unlike the other drivers, tagging drivers don't have compatible
strings to match against. For the ETHSW IP, the current driver is
reused as-is. My intention with the comment was simply to point out
that, if an issue ever arises that requires us to split the paths, we
can future-proof things by using DSA_TAG_PROTO_* identifiers.

Cheers,
Prabhakar