From: Bart Van Assche <bart.vanassche@sandisk.com>
Date: Wed, 31 Aug 2016 22:17:49 +0000 (-0700)
Subject: dm: mark request_queue dead before destroying the DM device
X-Git-Tag: v3.16.40~261
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=a51e427a433d5cd2389bee6ac72b5dc3cc0f2da4;p=thirdparty%2Fkernel%2Fstable.git

dm: mark request_queue dead before destroying the DM device

commit 3b785fbcf81c3533772c52b717f77293099498d3 upstream.

This avoids that new requests are queued while __dm_destroy() is in
progress.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
[js: use md->queue instead of non-present helper]
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index f62d4c8bd9f94..35caa4c17c3db 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2407,6 +2407,7 @@ EXPORT_SYMBOL_GPL(dm_device_name);
 
 static void __dm_destroy(struct mapped_device *md, bool wait)
 {
+	struct request_queue *q = md->queue;
 	struct dm_table *map;
 	int srcu_idx;
 
@@ -2417,6 +2418,10 @@ static void __dm_destroy(struct mapped_device *md, bool wait)
 	set_bit(DMF_FREEING, &md->flags);
 	spin_unlock(&_minor_lock);
 
+	spin_lock_irq(q->queue_lock);
+	queue_flag_set(QUEUE_FLAG_DYING, q);
+	spin_unlock_irq(q->queue_lock);
+
 	/*
 	 * Take suspend_lock so that presuspend and postsuspend methods
 	 * do not race with internal suspend.