linux-kernel - Re: [RFC PATCH v2 7/7] sched/fair: alternative way of accounting throttle time

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: <d2f72ac5650f740835ab09a562f24bf68ea581cd.camel@siemens.com>
Date: Wed, 23 Apr 2025 14:15:55 +0200
From: Florian Bezdeka <florian.bezdeka@...mens.com>
To: Aaron Lu <ziqianlu@...edance.com>
Cc: Valentin Schneider <vschneid@...hat.com>, Ben Segall
 <bsegall@...gle.com>,  K Prateek Nayak <kprateek.nayak@....com>, Peter
 Zijlstra <peterz@...radead.org>, Josh Don <joshdon@...gle.com>,  Ingo
 Molnar <mingo@...hat.com>, Vincent Guittot <vincent.guittot@...aro.org>, Xi
 Wang <xii@...gle.com>, 	linux-kernel@...r.kernel.org, Juri Lelli
 <juri.lelli@...hat.com>, Dietmar Eggemann <dietmar.eggemann@....com>,
 Steven Rostedt <rostedt@...dmis.org>, Mel Gorman	 <mgorman@...e.de>,
 Chengming Zhou <chengming.zhou@...ux.dev>, Chuyi Zhou	
 <zhouchuyi@...edance.com>, Jan Kiszka <jan.kiszka@...mens.com>
Subject: Re: [RFC PATCH v2 7/7] sched/fair: alternative way of accounting
 throttle time

On Wed, 2025-04-23 at 19:26 +0800, Aaron Lu wrote:
> On Tue, Apr 22, 2025 at 05:03:19PM +0200, Florian Bezdeka wrote:
> ... ...
> 
> > Right, I should have mentioned that crucial detail. Sorry.
> > 
> > I ported your series to 6.14.2 because we did/do not trust anything
> > newer yet for testing. The problematic workload was not available in
> > our lab at that time, so we had to be very carefully about deployed
> > kernel versions.
> > 
> > I'm attaching the backported patches now, so you can compare / review
> > if you like. Spoiler: The only differences are line numbers ;-)
> 
> I didn't notice any problem regarding backport after a quick look.
> 
> May I know what kind of workload triggered this warning? I haven't been
> able to trigger it, I'll have to stare harder at the code.

There are a couple of containers running. Nothing special as far as I
can tell. Network, IO, at least one container heavily using the epoll
interface.

The system is still operating fine though...

Once again: PREEMPT_RT enabled, so maybe handling an IRQ over the
accounting code could happen? Looking at the warning again it looks
like unthrottle_cfs_rq() is called from IRQ context. Is that expected?

Best regards,
Florian