[ovs-dev] attaching ebpf program to openvswitch vport driver

[Nicolas Bouliane]

Hi,

I have a very simple ebpf program that just print something when a packet
goes through. When I attach the ebpf program to the TAP interface (tun
driver) of a virtual machine, I see the expected output as expected.

I'm monitoring with: cat /sys/kernel/debug/tracing/trace_pipe

When I attach my ebpf program to a vport openvswitch interface
# ethtool -i meta0
driver: openvswitch
[...]

The program gets attached:
# ip link show meta0
23: meta0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 xdpgeneric qdisc
noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/ether c6:55:c3:8a:4d:ae brd ff:ff:ff:ff:ff:ff
    prog/xdp id 52 tag fe78bc3a2d633899

I also see that it use xdpgeneric (as expected) since the driver doesn't
have native XDP support.

But it seems that that ebpf program is never called, I see no printed
output.

Does anyone ever tried something similar ?
Please let me know if I'm missing something

Kernel version: 4.14.91-1-generic

cheers,
Nick Bouliane