Re: [PATCH 0/4 RFC] BDI lifetime fix

[Jan Kara <jack@suse.cz>]

On Thu 26-01-17 22:15:06, Dan Williams wrote:
> On Thu, Jan 26, 2017 at 9:45 AM, Jan Kara <jack@suse.cz> wrote:
> > Hello,
> >
> > this patch series attempts to solve the problems with the life time of a
> > backing_dev_info structure. Currently it lives inside request_queue structure
> > and thus it gets destroyed as soon as request queue goes away. However
> > the block device inode still stays around and thus inode_to_bdi() call on
> > that inode (e.g. from flusher worker) may happen after request queue has been
> > destroyed resulting in oops.
> >
> > This patch set tries to solve these problems by making backing_dev_info
> > independent structure referenced from block device inode. That makes sure
> > inode_to_bdi() cannot ever oops. The patches are lightly tested for now
> > (they boot, basic tests with adding & removing loop devices seem to do what
> > I'd expect them to do ;). If someone is able to reproduce crashes on bdi
> > when device goes away, please test these patches.
> 
> This survives a several runs of the libnvdimm unit tests which stress
> del_gendisk() and blk_cleanup_queue(). I'll keep testing since the
> failure was intermittent, but this is looking good.

Can I add your Tested-by tag?

								Honza

-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR