diff options
| author | Omar Sandoval <osandov@fb.com> | 2017-03-01 10:42:38 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-03-12 06:37:27 +0100 |
| commit | cd3db55c64ae1ee46c3522d9681e5999f83989d6 (patch) | |
| tree | 4ca1033a845725dc47e35b0f22fe53ad15e1cc74 | |
| parent | 356d71df739877f18aa0ce1e0d7cb050d8fe874c (diff) | |
loop: fix LO_FLAGS_PARTSCAN hang
commit e02898b423802b1f3a3aaa7f16e896da069ba8f7 upstream.
loop_reread_partitions() needs to do I/O, but we just froze the queue,
so we end up waiting forever. This can easily be reproduced with losetup
-P. Fix it by moving the reread to after we unfreeze the queue.
Fixes: ecdd09597a57 ("block/loop: fix race between I/O and set_status")
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/block/loop.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index b584f11b81ac..cec36d5c24f5 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1153,13 +1153,6 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) (info->lo_flags & LO_FLAGS_AUTOCLEAR)) lo->lo_flags ^= LO_FLAGS_AUTOCLEAR; - if ((info->lo_flags & LO_FLAGS_PARTSCAN) && - !(lo->lo_flags & LO_FLAGS_PARTSCAN)) { - lo->lo_flags |= LO_FLAGS_PARTSCAN; - lo->lo_disk->flags &= ~GENHD_FL_NO_PART_SCAN; - loop_reread_partitions(lo, lo->lo_device); - } - lo->lo_encrypt_key_size = info->lo_encrypt_key_size; lo->lo_init[0] = info->lo_init[0]; lo->lo_init[1] = info->lo_init[1]; @@ -1174,6 +1167,14 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) exit: blk_mq_unfreeze_queue(lo->lo_queue); + + if (!err && (info->lo_flags & LO_FLAGS_PARTSCAN) && + !(lo->lo_flags & LO_FLAGS_PARTSCAN)) { + lo->lo_flags |= LO_FLAGS_PARTSCAN; + lo->lo_disk->flags &= ~GENHD_FL_NO_PART_SCAN; + loop_reread_partitions(lo, lo->lo_device); + } + return err; } |