Re: [PATCH] workqueue: Fix memory ordering race in queue_work*()

From: Herbert Xu
Date: Tue Aug 16 2022 - 03:35:15 EST


Tejun Heo <tj@xxxxxxxxxx> 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@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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