block: fix deadlock in blk_abort_queue() for drivers that readd to timeout list

blk_abort_queue() iterates the timeout list and aborts each request on the
list, but if the driver error handling readds a request to the timeout list
during this processing, we could be looping forever. Fix this by splicing
current entries to a local list and run over that list instead.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Hannes Reinecke 2009-02-18 10:30:15 +01:00 committed by Jens Axboe
parent 41b8c853a4
commit be987fdb55
1 changed files with 8 additions and 1 deletions

View File

@ -209,12 +209,19 @@ void blk_abort_queue(struct request_queue *q)
{ {
unsigned long flags; unsigned long flags;
struct request *rq, *tmp; struct request *rq, *tmp;
LIST_HEAD(list);
spin_lock_irqsave(q->queue_lock, flags); spin_lock_irqsave(q->queue_lock, flags);
elv_abort_queue(q); elv_abort_queue(q);
list_for_each_entry_safe(rq, tmp, &q->timeout_list, timeout_list) /*
* Splice entries to local list, to avoid deadlocking if entries
* get readded to the timeout list by error handling
*/
list_splice_init(&q->timeout_list, &list);
list_for_each_entry_safe(rq, tmp, &list, timeout_list)
blk_abort_request(rq); blk_abort_request(rq);
spin_unlock_irqrestore(q->queue_lock, flags); spin_unlock_irqrestore(q->queue_lock, flags);