Thank you for responding so quickly ;-) On Sat, May 20, 2023 at 3:01 AM Martin KaFai Lau <martin.lau@xxxxxxxxx> wrote: > > On 5/19/23 5:07 AM, Zhouyi Zhou wrote: > > Dear developers: > > I compiled bpftool and bpf tests in mainline (2d1bcbc6cd70), > > but when I invoke: > > bpftool struct_ops register bpf_cubic.bpf.o > > > > the command line fail with: > > libbpf: struct_ops init_kern: struct tcp_congestion_ops data is not > > found in struct bpf_struct_ops_tcp_congestion_ops > > At the machine trying to register the bpf_cubic, please dump the vmlinux btf and > search for bpf_struct_ops_tcp_congestion_ops and paste it here: > > For example: > #> bpftool btf dump file /sys/kernel/btf/vmlinux > > ... > > [74578] STRUCT 'bpf_struct_ops_tcp_congestion_ops' size=256 vlen=3 > 'refcnt' type_id=145 bits_offset=0 > 'state' type_id=74569 bits_offset=32 > 'data' type_id=6241 bits_offset=512 OK [214398] STRUCT 'bpf_struct_ops_tcp_congestion_ops' size=256 vlen=3 'refcnt' type_id=298 bits_offset=0 'state' type_id=214224 bits_offset=32 'data' type_id=213704 bits_offset=512 Please tell me if I could provide any further information. You are of great help Thank you very much Zhouyi >