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Date: Tue, 27 Jan 2015 09:48:42 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Sasha Levin <sasha.levin@oracle.com>
Cc: Kirill Tkhai <ktkhai@parallels.com>, linux-kernel@vger.kernel.org,
        Oleg Nesterov <oleg@redhat.com>, Ingo Molnar <mingo@redhat.com>,
        Burke Libbey <burke.libbey@shopify.com>,
        Vladimir Davydov <vdavydov@parallels.com>,
        Kirill Tkhai <tkhai@yandex.ru>
Subject: Re: [PATCH] sched: Fix race between task_group and sched_task_group
Message-ID: <20150127084842.GO2896@worktop.programming.kicks-ass.net>
References: <1414405105.19914.169.camel@tkhai>
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On Mon, Jan 26, 2015 at 06:46:12PM -0500, Sasha Levin wrote:
> This seems to cause the following lockdep warning:

unlikely, the fork -> sched_move_task() was only used to establish that
rq->lock nests inside p->pi_lock, and there's a gazillion other ways to
establish that.

That said, its a right mess indeed. Let me stare a wee bit more at this
rats nets.