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

From: Tejun Heo
Date: Tue Aug 16 2022 - 12:26:53 EST


Hello,

On Tue, Aug 16, 2022 at 12:15:38PM +0800, Herbert Xu wrote:
> 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.

Alright, reverting.

Thanks.

--
tejun