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Date:   Wed, 19 Aug 2020 09:00:22 +0200
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Guenter Roeck <linux@roeck-us.net>
Cc:     Valdis =?utf-8?Q?Kl=C4=93tnieks?= <valdis.kletnieks@vt.edu>,
        Mark Starovoytov <mstarovoitov@marvell.com>,
        Igor Russkikh <irusskikh@marvell.com>,
        "David S. Miller" <davem@davemloft.net>,
        Greg KH <gregkh@linuxfoundation.org>,
        "Ahmed S. Darwish" <a.darwish@linutronix.de>,
        linux-kernel@vger.kernel.org, mingo@redhat.com, paulmck@kernel.org,
        peterz@infradead.org, rostedt@goodmis.org, tglx@linutronix.de,
        will@kernel.org
Subject: Re: [PATCH] Revert "seqlock: lockdep assert non-preemptibility on
 seqcount_t write"
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On 2020-08-18 17:56:49 [-0700], Guenter Roeck wrote:
> Nice catch. FWIW, there is no obvious reason why this would need to be atomic.
> The calling code does not set a lock, meaning there can be two (or more)
> callers entering this code. Weird, especially since the code looks like it
> would actually need a mutex to work correctly. It might be interesting to
> see what happens if there are, say, half a dozen scripts/processes trying
> to read the hwmon attribute introduced by this patch at the same time.

=> https://lkml.kernel.org/r/20200818161439.3dkf6jzp3vuwmvvh@linutronix.de

> Guenter

Sebastian