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Date:   Fri, 16 Jun 2023 14:37:04 +0200
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     linux-kernel@vger.kernel.org, Ben Segall <bsegall@google.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        Crystal Wood <swood@redhat.com>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Ingo Molnar <mingo@redhat.com>,
        John Stultz <jstultz@google.com>,
        Juri Lelli <juri.lelli@redhat.com>,
        Mel Gorman <mgorman@suse.de>,
        Steven Rostedt <rostedt@goodmis.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Valentin Schneider <vschneid@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Waiman Long <longman@redhat.com>, Will Deacon <will@kernel.org>
Subject: Re: [PATCH v2 1/4] sched/core: Provide sched_rtmutex() and expose
 sched work helpers
Message-ID: <20230616123704.lXQeCRiJ@linutronix.de>
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On 2023-05-25 17:25:07 [+0200], To Peter Zijlstra wrote:
> > if that works out this worry goes away.
> >=20
> > If we get PROVE_RAW_LOCK_NESTING usable, something like the below might
> > help out with the validation part...
>=20
> Okay. So if I don't collide with workqueue do you buy this or do you
> ask for something else. I'm not sure=E2=80=A6
>=20
> Regarding PROVE_RAW_LOCK_NESTING: If I boot -rc3 with `quiet' then I
> don't see any complains.
> Otherwise it is printk during boot (caller is holding raw_spinlock_t and
> then printk() calls to serial driver with spinlock_t).
> From time to time ppl send "fixes" for PROVE_RAW_LOCK_NESTING splats so
> I would guess they boot with `quiet' and there isn't much else. So we
> are getting close here I guess.
>=20
> Do you want me to test the suggested validation map somewhere? Because
> if it works, it could be queued.

Do you want just the validation map or is there something I'm missing?

Sebastian