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

From: Wanpeng Li
Date: Mon Jul 11 2016 - 03:25:41 EST


2016-06-16 20:57 GMT+08:00 Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>:
> 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