linux-kernel - Re: [PATCH net] net: dsa: mv88e6xxx: Fix switchdev error code

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] [day] [month] [year] [list]

Message-ID: <20250128163215.4yyf6xo5bd6kr6ns@skbuf>
Date: Tue, 28 Jan 2025 18:32:15 +0200
From: Vladimir Oltean <olteanv@...il.com>
To: Elliot Ayrey <Elliot.Ayrey@...iedtelesis.co.nz>
Cc: "andrew@...n.ch" <andrew@...n.ch>,
	"davem@...emloft.net" <davem@...emloft.net>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
	"netdev@...io-technology.com" <netdev@...io-technology.com>,
	"edumazet@...gle.com" <edumazet@...gle.com>,
	"kuba@...nel.org" <kuba@...nel.org>,
	"pabeni@...hat.com" <pabeni@...hat.com>
Subject: Re: [PATCH net] net: dsa: mv88e6xxx: Fix switchdev error code

On Sun, Jan 26, 2025 at 10:07:26PM +0000, Elliot Ayrey wrote:
> On Tue, 2024-12-17 at 10:54 +0100, Andrew Lunn wrote:
> > I just had a quick look at other users of call_switchdev_notifiers()
> > and all but vxlan_core.c and this one discarded the return
> > value. Would that be a better fix, making the code more uniform?
> > 
> > 	Andrew
> 
> Hi Andrew, I am hesitant to remove this error as it was very helpful
> during development and helped to diagnose some subtle issues that would
> have otherwise been very hard to notice.

Can you give more details about how you encountered this issue?
One could similarly argue that a call_switchdev_notifiers() error was
ignored until now, and maybe the system still did something reasonable
and thus, properly handling the error now risks introducing a regression
for them. No way to really know except if the commit author (you) makes
a reasonable analysis in the commit message leading to the conclusion
that the patch is worthy of backporting to stable kernels (i.e. fixes a
user-visible incorrect behavior).