From: Mikulas Patocka Date: Mon, 22 Jun 2009 09:12:13 +0000 (+0100) Subject: dm mpath: flush keventd queue in destructor X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=53b351f972a882ea8b6cdb19602535f1057c884a;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git dm mpath: flush keventd queue in destructor 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 --- diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index 838f01b1dd30..92bdcbb7c935 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -848,6 +848,7 @@ static void multipath_dtr(struct dm_target *ti) flush_workqueue(kmpath_handlerd); flush_workqueue(kmultipathd); + flush_scheduled_work(); free_multipath(m); }