XDP soxkets over loopback

Hi,

I've implemented an XDP socket that sends a simple UDP message to a 
server that listens on a specific port. I therefore create the packet 
with ethernet header, ip header, udp header and payload. This all works 
fine on an interface which is not the loopback interface, however if I 
try to use the loopback interface I see that my packet is send (I can 
see it in wireshark, all checksum are correct ), however the program the 
server never receives that packet. If I use netcat as a client to send 
to the server I see exactly the same data in wireshark as when I send it 
with XDP but in that case the packet arrives in the server.

My question is can you send over the loopback interface XDP TX to a 
standard udp socket or is this not possible ?Do I have to configure my 
loopback interface in a spacial way ?

All tips are welcome

Erik