Re: [PATCH v2 1/4] cgroup/cpuset: Fix partition root's cpuset.cpus update bug

[Tejun Heo]

On Fri, Mar 17, 2023 at 11:15:05AM -0400, Waiman Long wrote:
> It was found that commit 7a2127e66a00 ("cpuset: Call
> set_cpus_allowed_ptr() with appropriate mask for task") introduced a bug
> that corrupted "cpuset.cpus" of a partition root when it was updated.
> 
> It is because the tmp->new_cpus field of the passed tmp parameter
> of update_parent_subparts_cpumask() should not be used at all as
> it contains important cpumask data that should not be overwritten.
> Fix it by using tmp->addmask instead.
> 
> Also update update_cpumask() to make sure that trialcs->cpu_allowed
> will not be corrupted until it is no longer needed.
> 
> Fixes: 7a2127e66a00 ("cpuset: Call set_cpus_allowed_ptr() with appropriate mask for task")
> Signed-off-by: Waiman Long <longman@xxxxxxxxxx>

Applied to cgroup/for-6.3-fixes w/ stable cc'd.

Thanks.

-- 
tejun