From: Daniele Palmas dnlplm@gmail.com
[ Upstream commit eae7172f8141eb98e64e6e81acc9e9d5b2add127 ]
usbnet creates network interfaces with min_mtu = 0 and max_mtu = ETH_MAX_MTU.
These values are not modified by qmi_wwan when the network interface is created initially, allowing, for example, to set mtu greater than 1500.
When a raw_ip switch is done (raw_ip set to 'Y', then set to 'N') the mtu values for the network interface are set through ether_setup, with min_mtu = ETH_MIN_MTU and max_mtu = ETH_DATA_LEN, not allowing anymore to set mtu greater than 1500 (error: mtu greater than device maximum).
The patch restores the original min/max mtu values set by usbnet after a raw_ip switch.
Signed-off-by: Daniele Palmas dnlplm@gmail.com Acked-by: Bjørn Mork bjorn@mork.no Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/usb/qmi_wwan.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c index 3b7a3b8a5e067..5754bb6ca0eec 100644 --- a/drivers/net/usb/qmi_wwan.c +++ b/drivers/net/usb/qmi_wwan.c @@ -337,6 +337,9 @@ static void qmi_wwan_netdev_setup(struct net_device *net) netdev_dbg(net, "mode: raw IP\n"); } else if (!net->header_ops) { /* don't bother if already set */ ether_setup(net); + /* Restoring min/max mtu values set originally by usbnet */ + net->min_mtu = 0; + net->max_mtu = ETH_MAX_MTU; clear_bit(EVENT_NO_IP_ALIGN, &dev->flags); netdev_dbg(net, "mode: Ethernet\n"); }