Re: [PATCH v2 bpf-next 16/17] libbpf: Add support for attaching BPF programs to other BPF programs

@@ -3924,6 +3965,14 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
  		bpf_program__set_type(prog, prog_type);
  		bpf_program__set_expected_attach_type(prog, attach_type);
  		if (prog_type == BPF_PROG_TYPE_TRACING) {
+			if (attach_prog_fd) {
+				err = libbpf_get_prog_btf_id(attach_prog_fd, prog->section_name + 6);
+				if (err > 0) {
+					btf_id = err;
+					err = 0;
+					prog->attach_prog_fd = attach_prog_fd;
+				}
+			} else
  			err = libbpf_attach_btf_id_by_name(prog->section_name,