RX: VLAN strip, CRC strip, IP/TCP/UDP checksum. TX: IP/TCP/UDP checksum, TSO. Note that TSO has a problem: when enable TSO, F-Stack is much slower(Temporarily not resolved). So TSO is disabled by default. Edit config.ini to enable it.
BUG: When set config.ini: [kni] enable=1 method=reject tcp_port=80 Packets that not belond to tcp port 80 will not be transmitted to kernel.
In some cases such as AWS EC2, we must strip vlan tag. Edit the config.ini, set port.vlanstrip = 1.