diff options
| author | Ming Lei | 2020-09-01 18:07:38 +0800 |
|---|---|---|
| committer | Jens Axboe | 2020-09-01 08:34:08 -0600 |
| commit | cafe01ef8fcb248583038e1be071383530fe355a (patch) | |
| tree | af141eea39609d18694bc3a9f8531ce53c8c3254 | |
| parent | de1b0ee490eafdf65fac9eef9925391a8369f2dc (diff) | |
block: release disk reference in hd_struct_free_work
Commit e8c7d14ac6c3 ("block: revert back to synchronous request_queue removal")
stops to release request queue from wq context because that commit
supposed all blk_put_queue() is called in context which is allowed
to sleep. However, this assumption isn't true because we release disk's
reference in partition's percpu_ref's ->release() which doesn't allow
to sleep, because the ->release() is run via call_rcu().
Fixes this issue by moving put disk reference into hd_struct_free_work()
Fixes: e8c7d14ac6c3 ("block: revert back to synchronous request_queue removal")
Reported-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/partitions/core.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/block/partitions/core.c b/block/partitions/core.c index e62a98a8eeb7..5a18c8edabbc 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -278,6 +278,15 @@ static void hd_struct_free_work(struct work_struct *work) { struct hd_struct *part = container_of(to_rcu_work(work), struct hd_struct, rcu_work); + struct gendisk *disk = part_to_disk(part); + + /* + * Release the disk reference acquired in delete_partition here. + * We can't release it in hd_struct_free because the final put_device + * needs process context and thus can't be run directly from a + * percpu_ref ->release handler. + */ + put_device(disk_to_dev(disk)); part->start_sect = 0; part->nr_sects = 0; @@ -293,7 +302,6 @@ static void hd_struct_free(struct percpu_ref *ref) rcu_dereference_protected(disk->part_tbl, 1); rcu_assign_pointer(ptbl->last_lookup, NULL); - put_device(disk_to_dev(disk)); INIT_RCU_WORK(&part->rcu_work, hd_struct_free_work); queue_rcu_work(system_wq, &part->rcu_work); |