From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christian Brauner <brauner-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH 1/3] cgroup/cpuset: Make cpuset_fork() handle
 CLONE_INTO_CGROUP properly
Date: Thu, 6 Apr 2023 11:45:53 +0200
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To: Waiman Long <longman-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Cc: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Zefan Li <lizefan.x-EC8Uxl6Npydl57MIdRCFDg@public.gmane.org>, Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Juri Lelli <juri.lelli-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Dietmar Eggemann <dietmar.eggemann-5wv7dgnIgG8@public.gmane.org>, gscrivan-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org

On Fri, Mar 31, 2023 at 10:50:43AM -0400, Waiman Long wrote:
> By default, the clone(2) syscall spawn a child process into the same
> cgroup as its parent. With the use of the CLONE_INTO_CGROUP flag
> introduced by commit ef2c41cf38a7 ("clone3: allow spawning processes
> into cgroups"), the child will be spawned into a different cgroup which
> is somewhat similar to writing the child's tid into "cgroup.threads".
> 
> The current cpuset_fork() method does not properly handle the
> CLONE_INTO_CGROUP case where the cpuset of the child may be different
> from that of its parent.  Update the cpuset_fork() method to treat the
> CLONE_INTO_CGROUP case similar to cpuset_attach().
> 
> Since the newly cloned task has not been running yet, its actual
> memory usage isn't known. So it is not necessary to make change to mm
> in cpuset_fork().
> 
> Fixes: ef2c41cf38a7 ("clone3: allow spawning processes into cgroups")
> Signed-off-by: Waiman Long <longman-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> ---

Just two nits. I think this needs a Cc stable and it would be nice if
you could give Giuseppe a "Reported-by".