linux-kernel - Re: [PATCH v5 1/5] bug/kunit: Core support for suppressing warning backtraces

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: <20250602-phenomenal-turkey-of-hurricane-aadcde@houat>
Date: Mon, 2 Jun 2025 13:13:29 +0200
From: Maxime Ripard <mripard@...nel.org>
To: Peter Zijlstra <peterz@...radead.org>
Cc: Kees Cook <kees@...nel.org>, 
	Alessandro Carminati <acarmina@...hat.com>, linux-kselftest@...r.kernel.org, 
	Dan Carpenter <dan.carpenter@...aro.org>, Daniel Diaz <daniel.diaz@...aro.org>, 
	David Gow <davidgow@...gle.com>, Arthur Grillo <arthurgrillo@...eup.net>, 
	Brendan Higgins <brendan.higgins@...ux.dev>, Naresh Kamboju <naresh.kamboju@...aro.org>, 
	Andrew Morton <akpm@...ux-foundation.org>, Ville Syrjala <ville.syrjala@...ux.intel.com>, 
	Daniel Vetter <daniel@...ll.ch>, Guenter Roeck <linux@...ck-us.net>, 
	Alessandro Carminati <alessandro.carminati@...il.com>, Jani Nikula <jani.nikula@...el.com>, 
	Jeff Johnson <jeff.johnson@....qualcomm.com>, Josh Poimboeuf <jpoimboe@...nel.org>, 
	Shuah Khan <skhan@...uxfoundation.org>, Linux Kernel Functional Testing <lkft@...aro.org>, 
	dri-devel@...ts.freedesktop.org, kunit-dev@...glegroups.com, linux-kernel@...r.kernel.org, 
	Mark Rutland <mark.rutland@....com>
Subject: Re: [PATCH v5 1/5] bug/kunit: Core support for suppressing warning
 backtraces

On Sat, May 31, 2025 at 12:23:04PM +0200, Peter Zijlstra wrote:
> On Fri, May 30, 2025 at 10:48:47AM -0700, Kees Cook wrote:
> > On Fri, May 30, 2025 at 04:01:40PM +0200, Peter Zijlstra wrote:
> > > I'm not really concerned with performance here, but more with the size
> > > of the code emitted by WARN_ONCE(). There are a *ton* of WARN sites,
> > > while only one report_bug() and printk().
> > > 
> > > The really offensive thing is that this is for a feature most nobody
> > > will ever need :/
> > 
> > Well, it won't be enabled often -- this reminds me of ftrace: it needs
> > to work, but it'll be off most of the time.
> 
> Well, ftrace is useful, but when would I *ever* care about this stuff? I
> can't operate kunit

Why not?

> don't give a crap about kunit

That's your choice, of course, and it might not be useful to you anyway,
but it's *really* nice and closed a major gap in testing in some other
areas.

I'd still encourage you to try it, it might be worth your time.

> and if I were to magically run it, I would be more than capable of
> ignoring WARNs.

Yeah, it's not just about ignoring WARNs, but mostly about knowing which
ones you can ignore, and which ones you should fix.

We're getting at a point (on some subsystems I guess) where we actually
have a decent testing suite we can ask contributors to run and have all
tests passing.

We also want to ask them to fix whatever issue they might introduce :)

Thanks for your help on getting a cleaner solution!

Maxime

Download attachment "signature.asc" of type "application/pgp-signature" (274 bytes)