From: Greg Kroah-Hartman gregkh@linuxfoundation.org
From: Xie He xie.he.0141@gmail.com
commit f7d9d4854519fdf4d45c70a4d953438cd88e7e58 upstream.
For the devices in this driver, the default qdisc is "noqueue", because their "tx_queue_len" is 0.
In function "__dev_queue_xmit" in "net/core/dev.c", devices with the "noqueue" qdisc are specially handled. Packets are transmitted without being queued after a "dev->flags & IFF_UP" check. However, it's possible that even if this check succeeds, "ops->ndo_stop" may still have already been called. This is because in "__dev_close_many", "ops->ndo_stop" is called before clearing the "IFF_UP" flag.
If we call "netif_stop_queue" in "ops->ndo_stop", then it's possible in "__dev_queue_xmit", it sees the "IFF_UP" flag is present, and then it checks "netif_xmit_stopped" and finds that the queue is already stopped. In this case, it will complain that: "Virtual device ... asks to queue packet!"
To prevent "__dev_queue_xmit" from generating this complaint, we should not call "netif_stop_queue" in "ops->ndo_stop".
We also don't need to call "netif_start_queue" in "ops->ndo_open", because after a netdev is allocated and registered, the "__QUEUE_STATE_DRV_XOFF" flag is initially not set, so there is no need to call "netif_start_queue" to clear it.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xie He xie.he.0141@gmail.com Acked-by: Martin Schiller ms@dev.tdt.de Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/wan/lapbether.c | 3 --- 1 file changed, 3 deletions(-)
--- a/drivers/net/wan/lapbether.c +++ b/drivers/net/wan/lapbether.c @@ -286,7 +286,6 @@ static int lapbeth_open(struct net_devic return -ENODEV; }
- netif_start_queue(dev); return 0; }
@@ -294,8 +293,6 @@ static int lapbeth_close(struct net_devi { int err;
- netif_stop_queue(dev); - if ((err = lapb_unregister(dev)) != LAPB_OK) pr_err("lapb_unregister error: %d\n", err);