From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH] cgroup: Fix deadlock in cpu hotplug path
Date: Tue, 19 Dec 2017 05:39:58 -0800
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To: Prateek Sood <prsood@codeaurora.org>
Cc: peterz@infradead.org, avagin@gmail.com, mingo@kernel.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, sramana@codeaurora.org

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 <prsood@codeaurora.org>

Applied to cgroup/for-4.15-fixes.

Thanks a lot, Prateek.

-- 
tejun