From: Paolo Abeni pabeni@redhat.com
commit 40ee363c844fcb6ae0f1f5cfea68aed7e268c2f4 upstream.
Checking tunnel offloading, it turns out that offloading doesn't work as expected. The following script allows to reproduce the issue. Call it as `testscript DEVICE LOCALIP REMOTEIP NETMASK'
=== SNIP === if [ $# -ne 4 ] then echo "Usage $0 DEVICE LOCALIP REMOTEIP NETMASK" exit 1 fi DEVICE="$1" LOCAL_ADDRESS="$2" REMOTE_ADDRESS="$3" NWMASK="$4" echo "Driver: $(ethtool -i ${DEVICE} | awk '/^driver:/{print $2}') " ethtool -k "${DEVICE}" | grep tx-udp echo echo "Set up NIC and tunnel..." ip addr add "${LOCAL_ADDRESS}/${NWMASK}" dev "${DEVICE}" ip link set "${DEVICE}" up sleep 2 ip link add vxlan1 type vxlan id 42 \ remote "${REMOTE_ADDRESS}" \ local "${LOCAL_ADDRESS}" \ dstport 0 \ dev "${DEVICE}" ip addr add fc00::1/64 dev vxlan1 ip link set vxlan1 up sleep 2 rm -f vxlan.pcap echo "Running tcpdump and iperf3..." ( nohup tcpdump -i any -w vxlan.pcap >/dev/null 2>&1 ) & sleep 2 iperf3 -c fc00::2 >/dev/null pkill tcpdump echo echo -n "Max. Paket Size: " tcpdump -r vxlan.pcap -nnle 2>/dev/null \ | grep "${LOCAL_ADDRESS}.*> ${REMOTE_ADDRESS}.*OTV" \ | awk '{print $8}' | awk -F ':' '{print $1}' \ | sort -n | tail -1 echo ip link del vxlan1 ip addr del ${LOCAL_ADDRESS}/${NWMASK} dev "${DEVICE}" === SNAP ===
The expected outcome is
Max. Paket Size: 64904
This is what you see on igb, the code igc has been taken from. However, on igc the output is
Max. Paket Size: 1516
so the GSO aggregate packets are segmented by the kernel before calling igc_xmit_frame. Inside the subsequent call to igc_tso, the check for skb_is_gso(skb) fails and the function returns prematurely.
It turns out that this occurs because the feature flags aren't set entirely correctly in igc_probe. In contrast to the original code from igb_probe, igc_probe neglects to set the flags required to allow tunnel offloading.
Setting the same flags as igb fixes the issue on igc.
Fixes: 34428dff3679 ("igc: Add GSO partial support") Signed-off-by: Paolo Abeni pabeni@redhat.com Tested-by: Corinna Vinschen vinschen@redhat.com Acked-by: Sasha Neftin sasha.neftin@intel.com Tested-by: Nechama Kraus nechamax.kraus@linux.intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/intel/igc/igc_main.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/net/ethernet/intel/igc/igc_main.c +++ b/drivers/net/ethernet/intel/igc/igc_main.c @@ -5962,7 +5962,9 @@ static int igc_probe(struct pci_dev *pde if (pci_using_dac) netdev->features |= NETIF_F_HIGHDMA;
- netdev->vlan_features |= netdev->features; + netdev->vlan_features |= netdev->features | NETIF_F_TSO_MANGLEID; + netdev->mpls_features |= NETIF_F_HW_CSUM; + netdev->hw_enc_features |= netdev->vlan_features;
/* MTU range: 68 - 9216 */ netdev->min_mtu = ETH_MIN_MTU;