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Date:   Thu, 29 Jun 2023 09:25:05 -0400
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Subject: Re: [PATCH 1/3] cpuset: Allow setscheduler regardless of manipulated
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To:     =?UTF-8?Q?Michal_Koutn=c3=bd?= <mkoutny@suse.com>
Cc:     linux-kernel@vger.kernel.org, cgroups@vger.kernel.org,
        linux-kselftest@vger.kernel.org,
        Zefan Li <lizefan.x@bytedance.com>, Tejun Heo <tj@kernel.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Shuah Khan <shuah@kernel.org>
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From:   Waiman Long <longman@redhat.com>
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On 6/29/23 08:26, Michal Koutný wrote:
> On Thu, Jun 29, 2023 at 08:11:33AM -0400, Waiman Long <longman@redhat.com> wrote:
>> So I think you should just use
>> cgroup_subsys_on_dfl(cpuset_cgrp_subsys) as the v2 check if your focus
>> is just to prevent problem when enabling cpuset controller.
> I thought the bare cgroup_subsys_on_dfl(cpuset_cgrp_subsys) is not used
> in cpuset.c but I was wrong -- yes, I'll change this.
>
>> This change will likely conflict with the latest cpuset change on tracking #
>> of dl tasks in a cpuset. You will have to, at least, move the dl task check
>> before the security_task_setscheduler() check.
>>
>> Another fact about cpuset controller enabling is that both cpus_allowed and
>> mems_allowed are empty at that point. You may also add these checks as a
>> preconditions for disabling the security_task_setscheduler check.
> Ah, I will rebase on fresh mainline (or do you mean another reference?).

Yes, those changes have just been merged into the mainline.

Cheers,
Longman