linux-kernel - Re: [PATCH sched_ext/for-6.13-fixes] sched_ext: Fix dsq_local

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: <Z5IOpOD9cs2fLaIg@gpd3>
Date: Thu, 23 Jan 2025 10:40:52 +0100
From: Andrea Righi <arighi@...dia.com>
To: Ihor Solodrai <ihor.solodrai@...me>
Cc: Tejun Heo <tj@...nel.org>, sched-ext@...a.com, kernel-team@...a.com,
	linux-kernel@...r.kernel.org, bpf <bpf@...r.kernel.org>
Subject: Re: [PATCH sched_ext/for-6.13-fixes] sched_ext: Fix dsq_local_on
 selftest

On Wed, Jan 22, 2025 at 07:10:00PM +0000, Ihor Solodrai wrote:
> 
> On Tuesday, January 21st, 2025 at 5:40 PM, Tejun Heo <tj@...nel.org> wrote:
> 
> > 
> > 
> > Hello, sorry about the delay.
> > 
> > On Wed, Jan 15, 2025 at 11:50:37PM +0000, Ihor Solodrai wrote:
> > ...
> > 
> > > 2025-01-15T23:28:55.8238375Z [ 5.334631] sched_ext: BPF scheduler "dsp_local_on" disabled (runtime error)
> > > 2025-01-15T23:28:55.8243034Z [ 5.335420] sched_ext: dsp_local_on: SCX_DSQ_LOCAL[_ON] verdict target cpu 1 not allowed for kworker/u8:1[33]
> > 
> > 
> > That's a head scratcher. It's a single node 2 cpu instance and all unbound
> > kworkers should be allowed on all CPUs. I'll update the test to test the
> > actual cpumask but can you see whether this failure is consistent or flaky?
> 
> I re-ran all the jobs, and all sched_ext jobs have failed (3/3).
> Previous time only 1 of 3 runs failed.
> 
> https://github.com/kernel-patches/vmtest/actions/runs/12798804552/job/36016405680

Oh I see what happens, SCX_DSQ_LOCAL_ON is (incorrectly) resolved to 0.

More exactly, none of the enum values are being resolved correctly, likely
due to the CO:RE enum refactoring. There’s probably something broken in
tools/testing/selftests/sched_ext/Makefile, I’ll take a look.

Thanks,
-Andrea