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Date: Mon, 1 Jun 2015 10:19:24 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
        ktkhai@parallels.com
Subject: Re: sched_setscheduler() vs idle_balance() race
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On Sat, May 30, 2015 at 03:08:26PM +0200, Mike Galbraith wrote:

> Seems trying to make the target invisible to balancing created a new
> race: dequeue target, do stuff that may drop rq->lock while it's
> dequeued, target sneaks into schedule(), dequeues itself (#2), boom.

Aw god yes, duh.

Fun little puzzle this. Lemme go think a bit.