MD: warn for potential deadlock

The personality thread shouldn't call mddev_suspend(). Because
mddev_suspend() will for all IO finish, but IO is handled in personality
thread, so this could cause deadlock. To trigger this early, add a
warning if mddev_suspend() is called from personality thread.

Suggested-by: NeilBrown <neilb@suse.com>
Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This commit is contained in:
Shaohua Li 2016-02-24 17:41:01 -08:00
parent 399146b80e
commit 70d9798b95
1 changed files with 1 additions and 0 deletions

View File

@ -305,6 +305,7 @@ static blk_qc_t md_make_request(struct request_queue *q, struct bio *bio)
*/
void mddev_suspend(struct mddev *mddev)
{
WARN_ON_ONCE(current == mddev->thread->tsk);
if (mddev->suspended++)
return;
synchronize_rcu();