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Sender: Tejun Heo <htejun@gmail.com>
Date:   Sun, 12 Jun 2022 16:55:13 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Waiman Long <longman@redhat.com>
Cc:     Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Jonathan Corbet <corbet@lwn.net>,
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        Andrew Morton <akpm@linux-foundation.org>,
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        Frederic Weisbecker <frederic@kernel.org>,
        Marcelo Tosatti <mtosatti@redhat.com>,
        Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>
Subject: Re: [PATCH v11 3/8] cgroup/cpuset: Allow no-task partition to have
 empty cpuset.cpus.effective
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On Sun, Jun 12, 2022 at 10:53:53PM -0400, Waiman Long wrote:
> Without this patch, cpus.effective will never be empty. It just falls back
> to its parent if it becomes empty. Now with an empty cpus.effective, I am

Yeah, that part is fine.

> afraid that if a task is somehow moved to such a cpuset, something bad may
> happen. So I add this check as a safeguard.

But how would that happen? A lot of other things would break too if that
were to happen.

Thanks.

-- 
tejun