Re: sched: fair: NULL ptr deref in check_preempt_wakeup

From: Sasha Levin
Date: Wed Feb 19 2014 - 13:11:06 EST


On 02/17/2014 09:26 PM, Michael wang wrote:
On 02/17/2014 05:20 PM, Peter Zijlstra wrote:
[snip]
>> static void switched_to_fair(struct rq *rq, struct task_struct *p)
>> {
>>- if (!p->se.on_rq)
>>+ struct sched_entity *se = &p->se;
>>+#ifdef CONFIG_FAIR_GROUP_SCHED
>>+ se->depth = se->parent ? se->parent->depth + 1 : 0;
>>+#endif
>>+ if (!se->on_rq)
>> return;
>>
>> /*
>
>Yes indeed. My first idea yesterday was to put it in set_task_rq() to be
>absolutely sure we catch all; but if this is sufficient its better.
Agree, let's wait for Sasha's testing result then:)

I took my time with testing it seems I'm hitting new issues with both sched and mm, and I've wanted to confirm I don't see this one any more.

It does seem like this patch fixes the problem for me, so:

Tested-by: Sasha Levin <sasha.levin@xxxxxxxxxx>


Thanks,
Sasha
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/