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Date:   Fri, 20 Oct 2023 12:48:02 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Mark Rutland <mark.rutland@arm.com>
Cc:     Rong Tao <rtoax@foxmail.com>, elver@google.com,
        linux-kernel@vger.kernel.org, rongtao@cestc.cn, tglx@linutronix.de
Subject: Re: [PATCH v2] stop_machine: Avoid potential non-atomic read of
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On Fri, Oct 20, 2023 at 11:23:37AM +0100, Mark Rutland wrote:

> > And replace smp_wmb()+WRITE_ONCE() with smp_store_release().
> 
> This is also fine, but feels like a logically separate change.

Agreed, and please take this opportunity to write a comment with the
barrier.