can: Do not call dev_put if restart timer is running upon close

commit ab48b03ec9ae1840a1e427e2375bd0d9d554b4ed upstream.

If the restart timer is running due to BUS-OFF and the device is
disconnected an dev_put will decrease the usage counter to -1 thus
blocking the interface removal, resulting in the following dmesg
lines repeating every 10s:
can: notifier: receive list not found for dev can0
can: notifier: receive list not found for dev can0
can: notifier: receive list not found for dev can0
unregister_netdevice: waiting for can0 to become free. Usage count = -1

Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index 25695bde0549138a572f2eeb414f686af869051f..a3190574c3e6544ca5e924c38a9bcfd5946c4acb 100644 (file)
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -569,8 +569,7 @@ void close_candev(struct net_device *dev)
 {
        struct can_priv *priv = netdev_priv(dev);
 
-       if (del_timer_sync(&priv->restart_timer))
-               dev_put(dev);
+       del_timer_sync(&priv->restart_timer);
        can_flush_echo_skb(dev);
 }
 EXPORT_SYMBOL_GPL(close_candev);