Re: [GIT PULL] Queue free fix (was Re: [PATCH] block: Free queue resources at blk_release_queue())

[Mike Snitzer <snitzer@redhat.com>]

On Mon, Oct 31 2011 at  9:00am -0400,
Heiko Carstens <heiko.carstens@de.ibm.com> wrote:

> On Mon, Oct 31, 2011 at 08:46:06PM +0900, Jun'ichi Nomura wrote:
> > Hm, dm_softirq_done is generic completion code of original
> > request in dm-multipath.
> > So oops here might be another manifestation of use-after-free.
> > 
> > Do you always hit the oops at the same address?
> 
> I think we saw this bug the first time. But before that the scsi
> logging level was higher. Gonzalo is trying to recreate it with
> the same (old) scsi logging level.
> Afterwards we will try with barrier=0.
> 
> Both on v3.0.7 btw.
> 
> > Could you find corresponding source code line for
> > the crashed address, dm_softirq_done+0x72/0x140,
> > and which pointer was invalid?
> 
> It crashes in the inlined function dm_done() when trying to
> dereference tio (aka clone->end_io_data):
> 
> static void dm_done(struct request *clone, int error, bool mapped)
> {
>         int r = error;
>         struct dm_rq_target_io *tio = clone->end_io_data;
>         dm_request_endio_fn rq_end_io = tio->ti->type->rq_end_io;

Hi,

Which underlying storage driver is being used by this multipath device?

Thanks,
Mike