drbd: fix potential list_add corruption
authorLars Ellenberg <lars.ellenberg@linbit.com>
Wed, 22 Aug 2012 12:59:06 +0000 (14:59 +0200)
committerPhilipp Reisner <philipp.reisner@linbit.com>
Fri, 9 Nov 2012 13:08:21 +0000 (14:08 +0100)
commitb792b655cdf79d4d90b4d46fa37e260ba0296850
tree3880fc3b0a90a1d83ab8e53c31efc10ff856bedc
parentbc317a9ecd641b78a4b237cb22b30ecf11443c77
drbd: fix potential list_add corruption

If the md_sync_timer triggers a second time,
while the work queued during the first time is still pending,
this could result in list_add() of an already added item,
and corrupt the work item list.

This likely only triggered because of the erroneous
batch-dequeueing of work items fixed with
  drbd: dequeue single work items in wait_for_work()

Still, skip queueing if md_sync_work is already queued.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
drivers/block/drbd/drbd_main.c