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

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

[Alexander Stein]

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>
---
 drivers/net/can/dev.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index b8f5cc9..a45a559 100644
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -609,8 +609,7 @@ 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);
-- 
1.7.8.6

Re: [PATCH] can: Do not call dev_put if restart timer is running upon close

[Marc Kleine-Budde]

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On 11/27/2012 08:52 AM, Alexander Stein wrote:
> 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>

Looks good, I'll put stable on Cc.

Thanks,
Marc

-- 
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