Re: [PATCH v9 1/7] cgroup/cpuset: Don't let child cpusets restrict parent in default hierarchy

[Tejun Heo]

On Sun, Dec 05, 2021 at 01:32:14PM -0500, Waiman Long wrote:
> In validate_change(), there is a check since v2.6.12 to make sure that
> each of the child cpusets must be a subset of a parent cpuset.  IOW, it
> allows child cpusets to restrict what changes can be made to a parent's
> "cpuset.cpus". This actually violates one of the core principles of the
> default hierarchy where a cgroup higher up in the hierarchy should be
> able to change configuration however it sees fit as deligation breaks
> down otherwise.
> 
> To address this issue, the check is now removed for the default hierarchy
> to free parent cpusets from being restricted by child cpusets. The
> check will still apply for legacy hierarchy.
> 
> Suggested-by: Tejun Heo <tj@xxxxxxxxxx>
> Signed-off-by: Waiman Long <longman@xxxxxxxxxx>

Applied to cgroup/for-5.17.

Thanks.

-- 
tejun