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Date: Thu, 10 Oct 2024 10:00:45 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: John Stultz <jstultz@google.com>
Cc: LKML <linux-kernel@vger.kernel.org>, Juri Lelli <juri.lelli@redhat.com>,
 Joel Fernandes <joelaf@google.com>, Qais Yousef <qyousef@layalina.io>, Ingo
 Molnar <mingo@redhat.com>, Peter Zijlstra <peterz@infradead.org>, Vincent
 Guittot <vincent.guittot@linaro.org>, Dietmar Eggemann
 <dietmar.eggemann@arm.com>, Valentin Schneider <vschneid@redhat.com>, Ben
 Segall <bsegall@google.com>, Zimuzo Ezeozue <zezeozue@google.com>, Mel
 Gorman <mgorman@suse.de>, Will Deacon <will@kernel.org>, Waiman Long
 <longman@redhat.com>, Boqun Feng <boqun.feng@gmail.com>, "Paul E. McKenney"
 <paulmck@kernel.org>, Metin Kaya <Metin.Kaya@arm.com>, Xuewen Yan
 <xuewen.yan94@gmail.com>, K Prateek Nayak <kprateek.nayak@amd.com>, Thomas
 Gleixner <tglx@linutronix.de>, Daniel Lezcano <daniel.lezcano@linaro.org>,
 kernel-team@android.com, "Connor O'Brien" <connoro@google.com>
Subject: Re: [RESEND x3][PATCH v12 2/7] locking/mutex: Make mutex::wait_lock
 irq safe
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On Wed,  9 Oct 2024 16:53:35 -0700
John Stultz <jstultz@google.com> wrote:

> From: Juri Lelli <juri.lelli@redhat.com>
> 
> mutex::wait_lock might be nested under rq->lock.
> 
> Make it irq safe then.

Can you expand on this please?

If the mutex:wait_lock might be taken under an rq->lock, doesn't that mean
a mutex was taken under rq->lock? Or is it something internal?

This change log needs to be more explicit.

-- Steve