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Date:   Thu, 13 Feb 2020 08:56:45 -0500
From:   Tejun Heo <tj@kernel.org>
To:     Qais Yousef <qais.yousef@arm.com>
Cc:     Li Zefan <lizefan@huawei.com>,
        Johannes Weiner <hannes@cmpxchg.org>, cgroups@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] cgroup/cpuset: Fix a race condition when reading cpuset.*
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Hello,

On Thu, Feb 13, 2020 at 11:50:16AM +0000, Qais Yousef wrote:
> I ran 500 iterations of cpuset_hotplug_test.sh on the branch, it passed.
> 
> I also cherry-picked commit 6426bfb1d5f0 ("cpuset: Make cpuset hotplug synchronous")
> into v5.6-rc1 and ran 100 iterations and it passed too.

Awesome, thanks for verifying.

> While investigating the problem, I could reproduce it all the way back to v5.0.
> Stopped there so earlier versions could still have the problem.
> 
> Do you think it's worth porting the change to stable trees? Admittedly the
> problem should be benign, but it did trigger an LTP failure.

I'm afraid not. It's not an issue which would affect actual use cases
and there's (as always) some risks involved with backporting it, so
the benefit just doesn't seem justifiable here.

Thanks.

-- 
tejun