On Thu, Jan 26, 2017 at 9:45 AM, Jan Kara <jack@xxxxxxx> 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. > I'd also appreciate if people had a look whether the approach I took looks > sensible. Looks sensible, just the kref comment. I also don't see a need to try to tag on the bdi device name reuse into this series. I'm wondering if we can handle that separately with device_rename(bdi->dev, ...) when we know scsi is done with the old bdi but it has not finished being deleted -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
