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| author | Jan Kara <jack@suse.cz> | 2017-02-08 08:05:56 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2017-03-02 16:08:35 -0700 |
| commit | 165a5e22fafb127ecb5914e12e8c32a1f0d3f820 (patch) | |
| tree | 844b4541dcc7edd35feac79dfda0c25312d51ade /block/genhd.c | |
| parent | 113285b473824922498d07d7f82459507b9792eb (diff) | |
| download | linux-0-day-165a5e22fafb127ecb5914e12e8c32a1f0d3f820.tar.gz linux-0-day-165a5e22fafb127ecb5914e12e8c32a1f0d3f820.tar.xz | |
block: Move bdi_unregister() to del_gendisk()
Commit 6cd18e711dd8 "block: destroy bdi before blockdev is
unregistered." moved bdi unregistration (at that time through
bdi_destroy()) from blk_release_queue() to blk_cleanup_queue() because
it needs to happen before blk_unregister_region() call in del_gendisk()
for MD. SCSI though will free up the device number from sd_remove()
called through a maze of callbacks from device_del() in
__scsi_remove_device() before blk_cleanup_queue() and thus similar races
as described in 6cd18e711dd8 can happen for SCSI as well as reported by
Omar [1].
Moving bdi_unregister() to del_gendisk() works for MD and fixes the
problem for SCSI since del_gendisk() gets called from sd_remove() before
freeing the device number.
This also makes device_add_disk() (calling bdi_register_owner()) more
symmetric with del_gendisk().
[1] http://marc.info/?l=linux-block&m=148554717109098&w=2
Tested-by: Lekshmi Pillai <lekshmicpillai@in.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Tested-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block/genhd.c')
| -rw-r--r-- | block/genhd.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/block/genhd.c b/block/genhd.c index 2f444b87a5f24..b26a5ea115d00 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -681,6 +681,11 @@ void del_gendisk(struct gendisk *disk) disk->flags &= ~GENHD_FL_UP; sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi"); + /* + * Unregister bdi before releasing device numbers (as they can get + * reused and we'd get clashes in sysfs). + */ + bdi_unregister(disk->queue->backing_dev_info); blk_unregister_queue(disk); blk_unregister_region(disk_devt(disk), disk->minors); |