block: move q->unplug_work initialization

modprobe loop; rmmod loop effectively creates a blk_queue and destroys it
which results in q->unplug_work being canceled without it ever being
initialized.

Therefore, move the initialization of q->unplug_work from
blk_queue_make_request() to blk_alloc_queue*().

Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2 files changed, 1 insertions, 2 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index 8517264eb71e..fcbd56dd41fa 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -515,6 +515,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
         init_timer(&q->unplug_timer);
         setup_timer(&q->timeout, blk_rq_timed_out_timer, (unsigned long) q);
         INIT_LIST_HEAD(&q->timeout_list);
+        INIT_WORK(&q->unplug_work, blk_unplug_work);
 
         kobject_init(&q->kobj, &blk_queue_ktype);
 
diff --git a/block/blk-settings.c b/block/blk-settings.c
index b21dcdb64151..41392fbe19ff 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -141,8 +141,6 @@ void blk_queue_make_request(struct request_queue *q, make_request_fn *mfn)
         if (q->unplug_delay == 0)
                 q->unplug_delay = 1;
 
-        INIT_WORK(&q->unplug_work, blk_unplug_work);
-
         q->unplug_timer.function = blk_unplug_timeout;
         q->unplug_timer.data = (unsigned long)q;