When handling 'BPF_JMP | BPF_CALL' in the x86 do_jit() for entry_tc, three cases arise: 1. bpf_get_smp_processor_id() 2. subprog_tc1() 3. subprog_tc2() At this point in x86 do_jit() for entry_tc, entry_tc is considered tail_call_reachable. The check 'bool pseudo_call = src_reg == BPF_PSEUDO_CALL' is used to determine whether to call a subprogram. The question is: when should tailcall info be propagated? Should it be when entry_tc is tail_call_reachable, even if subprog_tc2 is called, or when subprog_tc1 is specifically tail_call_reachable? I believe it is better to propagate the tailcall info when subprog_tc1 is tail_call_reachable. Thanks, Leon
