Re: oops in __delayacct_blkio_ticks with 2.6.18-rc4

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Olaf Hering wrote:
> On Tue, Aug 22, Shailabh Nagar wrote:
> 
> 
>>Olaf Hering wrote:
>>
>>>https://bugzilla.novell.com/show_bug.cgi?id=200526
>>>
>>
>>Thanks for detecting this.
>>
>>I suspect the oops is caused by a reading of /proc/<tgid>/stat for some task
>>that is late in exit. Currently tsk->delays is being freed up too early (before
>>the tsk is removed from the tasklist).
>>
>>Could you try the patch below ? It was unclear from the bug what userspace
>>actions were being done to reproduce the oops - I suspect some kind of
>>reading of /proc/.../stat for all processes ?
> 
> 
> I dont have a way to trigger it. The commands were 'w' and 'pstree'.

Ok. Using the following two commands allowed the original oops to be
triggered on an 8-way pretty quickly:

while : ; do usleep 10 > /dev/null ; done

while : ; do cat /proc/[0-9]???*/stat ; done

(where the regex for catching the newly forking/exiting tasks
can be adjusted to the right range of ids being spawned by the
first command)

Applying the patch I sent solves the problem. I'm doing some more
testing and will submit the patch formally shortly.

Thanks,
Shailabh




-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux