Patch "block: wake up all tasks blocked in get_request()" has been added to the 4.9-stable tree

Patch "block: wake up all tasks blocked in get_request()" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    block: wake up all tasks blocked in get_request()

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     block-wake-up-all-tasks-blocked-in-get_request.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Tue Dec 12 13:26:17 CET 2017
From: Ming Lei <ming.lei@redhat.com>
Date: Thu, 16 Nov 2017 08:08:44 +0800
Subject: block: wake up all tasks blocked in get_request()

From: Ming Lei <ming.lei@redhat.com>


[ Upstream commit 34d9715ac1edd50285168dd8d80c972739a4f6a4 ]

Once blk_set_queue_dying() is done in blk_cleanup_queue(), we call
blk_freeze_queue() and wait for q->q_usage_counter becoming zero. But
if there are tasks blocked in get_request(), q->q_usage_counter can
never become zero. So we have to wake up all these tasks in
blk_set_queue_dying() first.

Fixes: 3ef28e83ab157997 ("block: generic request_queue reference counting")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 block/blk-core.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -527,8 +527,8 @@ void blk_set_queue_dying(struct request_
 
 		blk_queue_for_each_rl(rl, q) {
 			if (rl->rq_pool) {
-				wake_up(&rl->wait[BLK_RW_SYNC]);
-				wake_up(&rl->wait[BLK_RW_ASYNC]);
+				wake_up_all(&rl->wait[BLK_RW_SYNC]);
+				wake_up_all(&rl->wait[BLK_RW_ASYNC]);
 			}
 		}
 	}


Patches currently in stable-queue which might be from ming.lei@redhat.com are

queue-4.9/block-wake-up-all-tasks-blocked-in-get_request.patch