Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair

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From	Wanpeng Li <kernellwp@gmail.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair
Date	Mon, 11 Jul 2016 09:30:01 +0200
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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

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Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair Wanpeng Li <kernellwp@gmail.com> - 2016-07-11 09:30 +0200
  Re: [PATCH] sched/fair: do not announce throttled next buddy in  dequeue_task_fair Konstantin Khlebnikov <khlebnikov@yandex-team.ru> - 2016-07-11 10:20 +0200
  Re: [PATCH] sched/fair: do not announce throttled next buddy in  dequeue_task_fair Xunlei Pang <xpang@redhat.com> - 2016-07-11 10:30 +0200
    Re: [PATCH] sched/fair: do not announce throttled next buddy in  dequeue_task_fair Xunlei Pang <xpang@redhat.com> - 2016-07-11 10:50 +0200
      Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair Wanpeng Li <kernellwp@gmail.com> - 2016-07-11 12:00 +0200
        Re: [PATCH] sched/fair: do not announce throttled next buddy in  dequeue_task_fair Xunlei Pang <xpang@redhat.com> - 2016-07-11 14:20 +0200
          Re: [PATCH] sched/fair: do not announce throttled next buddy in  dequeue_task_fair Konstantin Khlebnikov <khlebnikov@yandex-team.ru> - 2016-07-11 14:30 +0200
            Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair bsegall@google.com - 2016-07-12 19:30 +0200
              Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair Wanpeng Li <kernellwp@gmail.com> - 2016-07-13 04:00 +0200
                Re: [PATCH] sched/fair: do not announce throttled next buddy in  dequeue_task_fair Xunlei Pang <xpang@redhat.com> - 2016-07-13 04:10 +0200
                Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair Wanpeng Li <kernellwp@gmail.com> - 2016-07-13 04:20 +0200
                Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair bsegall@google.com - 2016-07-13 19:10 +0200
                Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair Wanpeng Li <kernellwp@gmail.com> - 2016-07-14 14:20 +0200
                Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair bsegall@google.com - 2016-07-14 20:00 +0200
                Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair Wanpeng Li <kernellwp@gmail.com> - 2016-07-15 00:40 +0200
                Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair bsegall@google.com - 2016-07-15 00:50 +0200
                Re: [PATCH] sched/fair: do not announce throttled next buddy in dequeue_task_fair Wanpeng Li <kernellwp@gmail.com> - 2016-07-15 01:10 +0200

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