On Tue, Dec 19, 2017 at 12:56:57PM +0530, Prateek Sood wrote:

Deadlock during cgroup migration from cpu hotplug path when a task T is
being moved from source to destination cgroup.

...

Task T inserted a work item in the worklist of cpu0 low priority
worker pool. It is waiting for expedited grace period work item
to execute. This work item will only be executed once kworker/0:0
complete execution of cpuset_hotplug_workfn().

kworker/0:0 ==> Task T ==>kworker/0:0

In case of PF_EXITING task being migrated from source to destination
cgroup, migrate next available task in source cgroup.

Change-Id: I8874fb04479c136cae4dabd5c168c7749df66664
Signed-off-by: Prateek Sood <redacted>

Applied to cgroup/for-4.15-fixes.

Thanks a lot, Prateek.

-- 
tejun