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Sender: Tejun Heo <htejun@gmail.com>
Date:   Tue, 16 Aug 2022 06:26:43 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>, marcan@marcan.st,
        will@kernel.org, peterz@infradead.org, jirislaby@kernel.org,
        maz@kernel.org, mark.rutland@arm.com, boqun.feng@gmail.com,
        catalin.marinas@arm.com, oneukum@suse.com,
        roman.penyaev@profitbricks.com, asahi@lists.linux.dev,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org
Subject: Re: [PATCH] workqueue: Fix memory ordering race in queue_work*()
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 <YvsZ6vObgLaDeSZk@gondor.apana.org.au>
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Hello,

On Tue, Aug 16, 2022 at 12:15:38PM +0800, Herbert Xu wrote:
> Tejun Heo <tj@kernel.org> wrote:
> > 
> > Oh, tricky one and yeah you're absolutely right that it makes no sense to
> > not guarantee barrier semantics when already pending. I didn't even know
> > test_and_set_bit() wasn't a barrier when it failed. Thanks a lot for hunting
> > down and fixing this. Applied to wq/for-6.0-fixes.
> 
> Please revert this as test_and_set_bit was always supposed to be
> a full memory barrier.  This is an arch bug.

Alright, reverting.

Thanks.

-- 
tejun