TCP checksum appear broken on a lot of devices that
advertise NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM. This problem
becomes very visible/reproducable since the series
commit afb0bc972b526 ("Merge branch 'stacked_vlan_tso'").
In particular, the issue appeared consistently on bnx2 and be2net
drivers (not all drivers were tested).
This short series corrects this by disabling checksum offload
support on packets sent through Q-in-Q vlans if the underlying HW only
enables IP specific checksum features. We currently 'assume' that
any drivers setting NETIF_F_HW_CSUM can correclty pass checksum offsets
to HW. It is up to individual drivers to enable it properly through
ndo_features_check if they have some support for Q-in-Q vlans.
Additionally, be2net driver was fixed to make the proper call.
While looking at the drivers, it was also found that virtio-net ended
up disabling accelerations, which is unnecessary.
V2: Instead of disabling checksuming for all devices, only devices using
NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM are now affected by this change.
For drivers using NETIF_F_HW_CSUM, we will continue to use checksum
offloading. If any drivers are found to be broken, they would need
be fixed individually.
Vladislav Yasevich (3):
vlan: Fix tcp checksum offloads in Q-in-Q vlans
be2net: Fix offload features for Q-in-Q packets
virtio-net: enable TSO/checksum offloads for Q-in-Q vlans
drivers/net/ethernet/emulex/benet/be_main.c | 4 +++-
drivers/net/virtio_net.c | 1 +
include/linux/if_vlan.h | 10 ++++++++--
3 files changed, 12 insertions(+), 3 deletions(-)
--
2.7.4
