From 87ee7b112193bd081ba1a171fa5f6f39c429ef56 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 24 Apr 2014 08:51:47 -0600 Subject: blk-mq: fix race with timeouts and requeue events If a requeue event races with a timeout, we can get into the situation where we attempt to complete a request from the timeout handler when it's not start anymore. This causes a crash. So have the timeout handler check that REQ_ATOM_STARTED is still set on the request - if not, we ignore the event. If this happens, the request has now been marked as complete. As a consequence, we need to ensure to clear REQ_ATOM_COMPLETE in blk_mq_start_request(), as to maintain proper request state. Signed-off-by: Jens Axboe --- block/blk-mq.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'block/blk-mq.h') diff --git a/block/blk-mq.h b/block/blk-mq.h index 5fa14f19f752..b41a784de50d 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -51,6 +51,4 @@ void blk_mq_disable_hotplug(void); extern unsigned int *blk_mq_make_queue_map(struct blk_mq_tag_set *set); extern int blk_mq_update_queue_map(unsigned int *map, unsigned int nr_queues); -void blk_mq_add_timer(struct request *rq); - #endif -- cgit