[PATCH 4.9 40/78] s390/dasd: fix hanging offline processing due to canceled worker

[Greg Kroah-Hartman]

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

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

From: Stefan Haberland <sth@xxxxxxxxxxxxx>

[ Upstream commit 669f3765b755fd8739ab46ce3a9c6292ce8b3d2a ]

During offline processing two worker threads are canceled without
freeing the device reference which leads to a hanging offline process.

Reviewed-by: Jan Hoeppner <hoeppner@xxxxxxxxxxxxx>
Signed-off-by: Stefan Haberland <sth@xxxxxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/s390/block/dasd_eckd.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -2085,8 +2085,11 @@ static int dasd_eckd_basic_to_ready(stru
 
 static int dasd_eckd_online_to_ready(struct dasd_device *device)
 {
-	cancel_work_sync(&device->reload_device);
-	cancel_work_sync(&device->kick_validate);
+	if (cancel_work_sync(&device->reload_device))
+		dasd_put_device(device);
+	if (cancel_work_sync(&device->kick_validate))
+		dasd_put_device(device);
+
 	return 0;
 };