From: Mikulas Patocka The commit fe9cf30eb8186ef267d1868dc9f12f2d0f40835a moves dm table event submission from kmultipath queue to kernel kevent queue to avoid a deadlock. There is a possibility of race condition because kevent queue is not flushed in the multipath destructor. The scenario is: - some event happens and is queued to keventd - keventd thread is delayed due to scheuling latency or some other work - multipath device is destroyed - keventd now attempts to process work_struct that is residing in already released memory. The patch flushes the keventd queue in multipath constructor. I've already fixed similar bug in dm-raid1. Signed-off-by: Mikulas Patocka Signed-off-by: Alasdair G Kergon Cc: stable@kernel.org --- drivers/md/dm-mpath.c | 1 + 1 file changed, 1 insertion(+) Index: linux-2.6.30/drivers/md/dm-mpath.c =================================================================== --- linux-2.6.30.orig/drivers/md/dm-mpath.c +++ linux-2.6.30/drivers/md/dm-mpath.c @@ -848,6 +848,7 @@ static void multipath_dtr(struct dm_targ flush_workqueue(kmpath_handlerd); flush_workqueue(kmultipathd); + flush_scheduled_work(); free_multipath(m); }