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Message-ID: <a01585bc-03f8-e32c-ac46-99ac484a5e5d@redhat.com>
Date:   Tue, 4 Apr 2023 09:52:37 -0400
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Subject: Re: [PATCH 1/3] cgroup/cpuset: Make cpuset_fork() handle
 CLONE_INTO_CGROUP properly
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To:     =?UTF-8?Q?Michal_Koutn=c3=bd?= <mkoutny@suse.com>
Cc:     Tejun Heo <tj@kernel.org>, Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Christian Brauner <brauner@kernel.org>,
        cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
        Juri Lelli <juri.lelli@redhat.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        gscrivan@redhat.com
References: <20230331145045.2251683-1-longman@redhat.com>
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 <20230404091953.tcu3zg7npstk3ztc@blackpad>
From:   Waiman Long <longman@redhat.com>
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On 4/4/23 05:19, Michal Koutný wrote:
> On Mon, Apr 03, 2023 at 01:18:42PM -0400, Waiman Long <longman@redhat.com> wrote:
>> 1) PF_NO_SETAFFINITY flag - which won't be set in the case of fork() as it
>> is for kthread only.
>> 2) DL bandwidth - Juri has a cpuset outstanding to modify the way this check
>> is being done. I want to wait until it is settled before tackling this, if
>> necessary.
> BTW what about CLONE_INTO_CGROUP where the target cpuset has empty
> effective cpuset?
Good point. That will require a can_fork() method then. I will look into 
that.
>
>> 3) security_task_setscheduler() - the CLONE_INTO_CGROUP code has already
>> checked that, we don't need to duplicate the check.
> Not sure what this refers to.
It is just checking of the task the has privilege of running into that 
cgroup.
>
>> So we don't need a can_fork() check for now.
> Anyway, good breakdown. Could you please add it to the commit message
> too?

Yes, I can put that into the commit log.

Cheers,
Longman

> Regards,
> Michal