[PATCH 3.16 042/366] media: rc: oops in ir_timer_keyup after device unplug

[Ben Hutchings]

3.16.60-rc1 review patch.  If anyone has any objections, please let me know.

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

From: Sean Young <sean@xxxxxxxx>

commit 8d4068810d9926250dd2435719a080b889eb44c3 upstream.

If there is IR in the raw kfifo when ir_raw_event_unregister() is called,
then kthread_stop() causes ir_raw_event_thread to be scheduled, decode
some scancodes and re-arm timer_keyup. The timer_keyup then fires when
the rc device is long gone.

Signed-off-by: Sean Young <sean@xxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
[bwh: Backported to 3.16:
 - There's no timer_repeat to move
 - Adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
--- a/drivers/media/rc/rc-main.c
+++ b/drivers/media/rc/rc-main.c
@@ -1427,13 +1427,13 @@ void rc_unregister_device(struct rc_dev
 	if (!dev)
 		return;
 
-	del_timer_sync(&dev->timer_keyup);
-
 	clear_bit(dev->devno, ir_core_dev_number);
 
 	if (dev->driver_type == RC_DRIVER_IR_RAW)
 		ir_raw_event_unregister(dev);
 
+	del_timer_sync(&dev->timer_keyup);
+
 	/* Freeing the table should also call the stop callback */
 	ir_free_table(&dev->rc_map);
 	IR_dprintk(1, "Freed keycode table\n");