Re: [PATCH] audit: wait_for_auditd() should use TASK_UNINTERRUPTIBLE

From: Guy Streeter
Date: Wed May 29 2013 - 18:09:04 EST


On 05/29/2013 04:59 PM, Andrew Morton wrote:
> On Fri, 24 May 2013 19:39:25 +0200 Oleg Nesterov <oleg@xxxxxxxxxx> wrote:
>
>> audit_log_start() does wait_for_auditd() in a loop until
>> audit_backlog_wait_time passes or audit_skb_queue has a room.
>>
>> If signal_pending() is true this becomes a busy-wait loop,
>> schedule() in TASK_INTERRUPTIBLE won't block.
>
> And that's game over for a uniprocessor non-preempt machine, yes?
>
>> Reported-by: Guy Streeter <streeter@xxxxxxxxxx>
>
> And what did Guy report? "that looks screwy"? "my machine locked up"?
>

Our customer was in fact running a uniprocessor machine, and they reported a
system hang.
--Guy

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