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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Tejun Heo <tj@kernel.org>
Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
	Bert Karwatzki <spasswolf@web.de>, Michal Koutny <mkoutny@suse.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	kernel test robot <oliver.sang@intel.com>
Subject: Re: [PATCH v3 cgroup/for-7.0-fixes] cgroup: Fix cgroup_drain_dying()
 testing the wrong condition
Message-ID: <20260325180623.EcyNsp2L@linutronix.de>
References: <68d8881fd985a410c0f619f009334c28@kernel.org>
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In-Reply-To: <68d8881fd985a410c0f619f009334c28@kernel.org>

On 2026-03-25 07:23:48 [-1000], Tejun Heo wrote:
> cgroup_drain_dying() was using cgroup_is_populated() to test whether ther=
e are
> dying tasks to wait for. cgroup_is_populated() tests nr_populated_csets,
> nr_populated_domain_children and nr_populated_threaded_children, but
> cgroup_drain_dying() only needs to care about this cgroup's own tasks - w=
hether
> there are children is cgroup_destroy_locked()'s concern.
=E2=80=A6

Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

The only issue I see is if I delay the irq_work callback by a second.
Other than that, I don't see any problems.

Sebastian