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Date:   Tue, 16 Aug 2022 12:15:38 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Tejun Heo <tj@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
Cc:     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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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.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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