Receive active features on virtual network device
 

Hello,

So I have an interface eth0. On that, I created a virtual network interface if-vx (vxlan) using ip link add command. When I use ethtool -K eth0 tx off, I receive the set of features active on eth0 via __netdev_update_features() callback calling ndo_set_features() in my driver.

However, when I do the same on virtual interface (vxlan), ethtool -K if-vx tx off, I do not see a call to ndo_set_features() so my driver does not get to know if the feature is on or off. Any idea on how to retrieve the active feature bits on vxlan interface?

Any help is appreciated?

Thanks

The different interface type map to different driver.

Thanks for the reply. Shouldn't there be any API to send relevant information (offload information) to the driver running on eth0 interface as it acts as vtep?

For example, If I disable rx checksum offload on vxlan interface (ethtool -K if-vx rx off), it means rx checksum verification should not be performed by the hardware and guest will do it. However, my driver does not get to know this offload setting change on vxlan interface.

Is there any way I can retrieve this information? These two interface should be linked somehow I guess?

Thanks,
Ronak

Does eth0 interface support checksum offload?

Yes, it does support. But in case of encapsulation, eth0 will represent outer headers.

The physical interface support checksum offload only normally.