Hello, this is the third version of the patch series that 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. I gave some basic testing to the patches in KVM and on a real machine, Dan was running them with libnvdimm test suite which was previously triggering the oops and things look good. So patches should be reasonably healthy. Changes since v2: * Added Reviewed-by tags * Removed slab cache for backing_dev_info * Added patch to remove blkdev_get_backing_dev_info() Changes since v1: * Use kref instead of atomic_t for refcount * Get rid of free_on_put flag Honza -- 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
