Hey, I started trying out xdp programs recently and I was comparing what comes out of tcp dump and my test program. It seems like the first syn in the packet never appears in my logged out put, the rest of the packets do. I am using a vm and using the loopback interface and a virtual one created by docker, both will only start from the second outgoing packet. Tcpdump shows syn -> syn,ack -> ack. But the xdp program only starts from syn,ack then ack. Im logging using bpf_trace_printk and put the statement at the beginning of the section being loaded so something should at least print every time? Is there something Im over looking? Thanks and let me know if I can clarify anything. Matt
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