Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a2614255 authored by Jens Axboe's avatar Jens Axboe
Browse files

block: fix elevator_get_by_features() 



The lookup logic is broken - 'e' will never be NULL, even if the
list is empty. Maintain lookup hit in a separate variable instead.

Fixes: a0958ba7 ("block: Improve default elevator selection")
Reported-by: default avatarJulia Lawall <julia.lawall@lip6.fr>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent ebddd2a1

block/elevator.c

+7 −6
Original line number Diff line number Diff line
@@ -668,22 +668,23 @@ static struct elevator_type *elevator_get_default(struct request_queue *q) 
 */

static struct elevator_type *elevator_get_by_features(struct request_queue *q)

{

	struct elevator_type *e;

	struct elevator_type *e, *found = NULL;



	spin_lock(&elv_list_lock);



	list_for_each_entry(e, &elv_list, list) {

		if (elv_support_features(e->elevator_features,

					 q->required_elevator_features))

					 q->required_elevator_features)) {

			found = e;

			break;

		}

	}



	if (e && !try_module_get(e->elevator_owner))

		e = NULL;

	if (found && !try_module_get(found->elevator_owner))

		found = NULL;



	spin_unlock(&elv_list_lock);



	return e;

	return found;

}



/*