netdev - Re: [PATCH net v3] net: dsa: mt7530: fix impossible MDIO address and issue warning

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]

Date: Wed, 3 Jul 2024 03:07:02 +0200
From: Andrew Lunn <andrew@...n.ch>
To: Daniel Golle <daniel@...rotopia.org>
Cc: Arınç ÜNAL <arinc.unal@...nc9.com>,
	DENG Qingfang <dqfext@...il.com>,
	Sean Wang <sean.wang@...iatek.com>,
	Florian Fainelli <f.fainelli@...il.com>,
	Vladimir Oltean <olteanv@...il.com>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>,
	Matthias Brugger <matthias.bgg@...il.com>,
	AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>,
	Landen Chao <Landen.Chao@...iatek.com>,
	Frank Wunderlich <linux@...web.de>, Rob Herring <robh@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
	linux-mediatek@...ts.infradead.org, regressions@...ts.linux.dev
Subject: Re: [PATCH net v3] net: dsa: mt7530: fix impossible MDIO address and
 issue warning

On Wed, Jul 03, 2024 at 12:44:28AM +0100, Daniel Golle wrote:
> The MDIO address of the MT7530 and MT7531 switch ICs can be configured
> using bootstrap pins. However, there are only 4 possible options for the
> switch itself: 7, 15, 23 and 31. As in MediaTek's SDK the address of the
> switch is wrongly stated in the device tree as 0 (while in reality it is
> 31), warn the user about such broken device tree and make a good guess
> what was actually intended.
> 
> This is imporant also to not break compatibility with older Device Trees
> as with commit 868ff5f4944a ("net: dsa: mt7530-mdio: read PHY address of
> switch from device tree") the address in device tree will be taken into
> account, while before it was hard-coded to 0x1f.
> 
> Fixes: b8f126a8d543 ("net-next: dsa: add dsa support for Mediatek MT7530 switch")
> Signed-off-by: Daniel Golle <daniel@...rotopia.org>

Fun code. Not seen anything like this before.

Reviewed-by: Andrew Lunn <andrew@...n.ch>

    Andrew