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Date: Fri, 27 Mar 2026 10:22:59 -1000
From: Tejun Heo <tj@kernel.org>
To: Waiman Long <longman@redhat.com>
Cc: Chen Ridong <chenridong@huawei.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>,
	cgroups@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] cgroup/cpuset: Skip security check for hotplug induced
 v1 task migration
Message-ID: <acbnI21DC-W_uE2F@slm.duckdns.org>
References: <20260327201546.2463644-1-longman@redhat.com>
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In-Reply-To: <20260327201546.2463644-1-longman@redhat.com>

On Fri, Mar 27, 2026 at 04:15:46PM -0400, Waiman Long wrote:
> +	/*
> +	 * Set to true if a kthread is moving tasks away from a v1 cpuset with
> +	 * no CPUs
> +	 */
> +	kthread_move_task_from_empty_cs = !cpuset_v2() &&
> +					  cpumask_empty(oldcs->effective_cpus) &&
> +					  (current->flags & PF_KTHREAD);

PF_KTHREAD test seems odd. Can't you pass this in as a flag from hotplug
handler?

Thanks.

-- 
tejun