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From: Haggai Eran <haggaie@mellanox.com>
Subject: Re: [PATCHv9 1/3] rdmacg: Added rdma cgroup controller
Date: Thu, 3 Mar 2016 10:14:53 +0200
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To: Parav Pandit <pandit.parav@gmail.com>, Tejun Heo <tj@kernel.org>
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On 03/03/2016 05:18, Parav Pandit wrote:
> On Thu, Mar 3, 2016 at 1:28 AM, Parav Pandit <pandit.parav@gmail.com> wrote:
>> On Wed, Mar 2, 2016 at 11:09 PM, Tejun Heo <tj@kernel.org> wrote:
>>> Nothing seems to prevent @cg from going away if this races with
>>> @current being migrated to a different cgroup.  Have you run this with
>>> lockdep and rcu debugging enabled?  This should have triggered a
>>> warning.
> I am able to reproduce this race. Looking into how to address it.

If I understand correctly, task_css() requires rcu read lock being held.
Is task_get_css() suitable here?