From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH] cgroup: cgroup-v1: do not exclude cgrp_dfl_root
Date: Tue, 5 Oct 2021 06:14:23 -1000
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To: Vishal Verma <vverma-tWEdnPwa2b6ifxm/DiOjgA@public.gmane.org>
Cc: lizefan.x-EC8Uxl6Npydl57MIdRCFDg@public.gmane.org, hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org

On Mon, Oct 04, 2021 at 08:19:48PM +0000, Vishal Verma wrote:
> Found an issue within cgroup_attach_task_all() fn which seem
> to exclude cgrp_dfl_root (cgroupv2) while attaching tasks to
> the given cgroup. This was noticed when the system was running
> qemu/kvm with kernel vhost helper threads. It appears that the
> vhost layer which uses cgroup_attach_task_all() fn to assign the
> vhost kthread to the right qemu cgroup works fine with cgroupv1
> based configuration but not in cgroupv2. With cgroupv2, the vhost
> helper thread ends up just belonging to the root cgroup as is
> shown below:
...
> Suggested-by: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> Signed-off-by: Vishal Verma <vverma-tWEdnPwa2b6ifxm/DiOjgA@public.gmane.org>

Applied to cgroup/for-5.16.

Thanks.

-- 
tejun