[ 48/53] MD: Add del_timer_sync to mddev_suspend (fix nasty panic)

[Ben Hutchings]

3.2.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jonathan Brassow <jbrassow@xxxxxxxxxx>

commit 0d9f4f135eb6dea06bdcb7065b1e4ff78274a5e9 upstream.

Use del_timer_sync to remove timer before mddev_suspend finishes.

We don't want a timer going off after an mddev_suspend is called.  This is
especially true with device-mapper, since it can call the destructor function
immediately following a suspend.  This results in the removal (kfree) of the
structures upon which the timer depends - resulting in a very ugly panic.
Therefore, we add a del_timer_sync to mddev_suspend to prevent this.

Signed-off-by: NeilBrown <neilb@xxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/md/md.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 477eb2e..01233d8 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -391,6 +391,8 @@ void mddev_suspend(struct mddev *mddev)
 	synchronize_rcu();
 	wait_event(mddev->sb_wait, atomic_read(&mddev->active_io) == 0);
 	mddev->pers->quiesce(mddev, 1);
+
+	del_timer_sync(&mddev->safemode_timer);
 }
 EXPORT_SYMBOL_GPL(mddev_suspend);
 
-- 
1.7.10



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/