From: Peter Zijlstra <peterz@infradead.org>
To: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Cc: "Ingo Molnar" <mingo@redhat.com>, "Will Deacon" <will@kernel.org>,
"Boqun Feng" <boqun@kernel.org>,
"Juri Lelli" <juri.lelli@redhat.com>,
"Vincent Guittot" <vincent.guittot@linaro.org>,
"Dietmar Eggemann" <dietmar.eggemann@arm.com>,
"Steven Rostedt" <rostedt@goodmis.org>,
"Ben Segall" <bsegall@google.com>, "Mel Gorman" <mgorman@suse.de>,
"Valentin Schneider" <vschneid@redhat.com>,
"K Prateek Nayak" <kprateek.nayak@amd.com>,
"Waiman Long" <longman@redhat.com>,
"John Stultz" <jstultz@google.com>,
"André Almeida" <andrealmeid@igalia.com>,
"Thomas Gleixner" <tglx@linutronix.de>,
"Linux regressions mailing list" <regressions@lists.linux.dev>,
"Linux List Kernel Mailing" <linux-kernel@vger.kernel.org>
Subject: Re: [REGRESSION] sched/core merge 1c3b68f0d55b: futex_waitv lost wakeup hangs RE Engine games and PID 1 init
Date: Wed, 22 Apr 2026 15:45:19 +0200 [thread overview]
Message-ID: <20260422134519.GQ3102624@noisy.programming.kicks-ass.net> (raw)
In-Reply-To: <CABXGCsO5fKq2nD9nO8yO1z50ZzgCPWqueNXHANjntaswoOh2Dg@mail.gmail.com>
On Wed, Apr 22, 2026 at 03:48:16PM +0500, Mikhail Gavrilov wrote:
> On Tue, Apr 21, 2026 at 7:41 PM Peter Zijlstra <peterz@infradead.org> wrote:>
> > Specifically, see this thread:
> >
> > https://lore.kernel.org/r/95651a71-1adf-45ba-83eb-5744bc6d4a52@amd.com
>
> You're right — it is to blame, and I was about to follow up to say so.
>
> After sending the first mail I kept re-verifying markers with the
> stricter RE2+RE9 workload and found that 33c66eb5e984 (parent 1 of
> 1c3b68f0, which I had marked "good") actually reproduces the hang too.
> A third bisect run with the stricter workload converges unambiguously
> on:
>
> 25500ba7e77c ("locking/mutex: Remove the list_head from struct mutex")
>
> Parent b9bdd4b68404 ("locking/semaphore: Remove the list_head from struct
> semaphore"): good. 25500ba7e77c: bad.
Please test this:
https://lore.kernel.org/r/20260422092335.GH3102924@noisy.programming.kicks-ass.net
and reply there with your findings if possible.
prev parent reply other threads:[~2026-04-22 13:45 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-21 13:19 [REGRESSION] sched/core merge 1c3b68f0d55b: futex_waitv lost wakeup hangs RE Engine games and PID 1 init Mikhail Gavrilov
2026-04-21 13:53 ` Peter Zijlstra
2026-04-21 14:41 ` Peter Zijlstra
2026-04-22 10:48 ` Mikhail Gavrilov
2026-04-22 13:45 ` Peter Zijlstra [this message]
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