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From: Wanpeng Li <kernellwp@gmail.com>
Date: Mon, 11 Jul 2016 15:25:34 +0800
Message-ID: <CANRm+Cxo1q-GyWcSQfZ3S=FAL8opCi0uH=NVJcEFiLyf8dCbVQ@mail.gmail.com>
Subject: Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair
To: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        stable@vger.kernel.org
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2016-06-16 20:57 GMT+08:00 Konstantin Khlebnikov <khlebnikov@yandex-team.ru>:
> Hierarchy could be already throttled at this point. Throttled next
> buddy could trigger null pointer dereference in pick_next_task_fair().

There is cfs_rq->next check in pick_next_entity(), so how can null
pointer dereference happen?

Regards,
Wanpeng Li