On Sun 12-02-17 12:58:33, Tejun Heo wrote:

On Thu, Feb 09, 2017 at 01:44:24PM +0100, Jan Kara wrote:

quoted

Move bdev_unhash_inode() after invalidate_partition() as
invalidate_partition() looks up bdev and will unnecessarily recreate it
if bdev_unhash_inode() destroyed it. Also use part_devt() when calling
bdev_unhash_inode() instead of manually creating the device number.

Signed-off-by: Jan Kara <jack@suse.cz>

Acked-by: Tejun Heo <tj@kernel.org>

quoted

@@ -648,9 +648,8 @@ void del_gendisk(struct gendisk *disk)
 	disk_part_iter_init(&piter, disk,
 			     DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
 	while ((part = disk_part_iter_next(&piter))) {
-		bdev_unhash_inode(MKDEV(disk->major,
-					disk->first_minor + part->partno));
 		invalidate_partition(disk, part->partno);
+		bdev_unhash_inode(part_devt(part));
 		delete_partition(disk, part->partno);

So, before this patch, invalidate_partition() would have operated on a
newly created inode and thus wouldn't have actually invalidated the
existing bdev / mapping, right?

Yes, that is another effect. I'll add a note about this to the changelog.
Thanks for noting this.

								Honza

-- 
Jan Kara [off-list ref]
SUSE Labs, CR