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Date: Tue, 5 Jul 2016 14:41:29 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org,
        Sasha Levin <sasha.levin@oracle.com>,
        Yao Dongdong <yaodongdong@huawei.com>
Subject: Re: [PATCH] sched/core: really pretend early bootup to be a normal
 task
Message-ID: <20160705124129.GB30921@twins.programming.kicks-ass.net>
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On Tue, Jul 05, 2016 at 02:23:23PM +0300, Konstantin Khlebnikov wrote:
> Commit 1b537c7d1e58 ("sched/core: Remove check of p->sched_class") placed
> "current->sched_class = &fair_sched_class" before call of init_idle() which
> immediately set sched_class back to idle_sched_class.
> 
> This patch reverts this piece because after commit de9b8f5dcbd9 ("sched:
> Fix crash trying to dequeue/enqueue the idle thread") init_idle() doesn't
> call do_set_cpus_allowed() and nobody will dereference ->sched_class.

I don't understand, what is broken?