Re: Simple script that locks up my box with recent kernels

Jens Axboe
2006-11-22T10:57:13Z

On Wed, Nov 22 2006, Jesper Juhl wrote:
> On 22/11/06, Jens Axboe <jens.axboe@oracle.com> wrote:
> >On Tue, Nov 21 2006, Linus Torvalds wrote:
> >> I don't think we use any irq-disable locking in the VM itself, but I
> >could
> >> imagine some nasty situation with the block device layer getting into a
> >> deadlock with interrupts disabled when it runs out of queue entries and
> >> cannot allocate more memory..
> >
> >Not likely. Request allocation is done with GFP_NOIO and backed by a
> >memory pool, so as long the vm doesn't go totally nuts because
> >__GFP_WAIT is set, we should be safe there. If it did go crazy, I
> >suspect a sysrq-t would still work.
> >
> >If bouncing is involved for swap, we do have a potential deadlock issue
> >that isn't fixed yet. I just whipped up this completely untested patch,
> >it should shed some light on that issue.
> >
> Thanks Jens, I'll apply that later tonight and force a few lockups and
> see if I get any extra details with that patch.

Can you post a full dmesg too, as well as clarify which device holds the
swap space?

--
Jens Axboe