dm: don't report warning when doing deferred remove

commit b7cce3e upstream.

If dm_hash_remove_all was called from dm_deferred_remove, it would write
a warning "remove_all left %d open device(s)" if there are some other
devices active.

The warning is bogus, so let's disable it in this case.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: Zdenek Kabelac <zkabelac@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 2c140a2 ("dm: allow remove to be deferred")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Mikulas Patocka

drivers/md/dm-ioctl.c

@@ -384,7 +384,7 @@ static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool
 
 	up_write(&_hash_lock);
 
-	if (dev_skipped)
+	if (dev_skipped && !only_deferred)
 		DMWARN("remove_all left %d open device(s)", dev_skipped);
 }