On Tue, 25 Jul 2017 16:15:47 -0700, Jakub Kicinski wrote: > On Wed, 26 Jul 2017 00:59:49 +0200, Daniel Borkmann wrote: > > > @@ -418,6 +420,8 @@ static void test_bpf_obj_id(void) > > > nr_id_found++; > > > > > > err = bpf_obj_get_info_by_fd(prog_fd, &prog_info, > > > &info_len); > > > + prog_infos[i].jited_prog_insns = 0; > > > + prog_infos[i].xlated_prog_insns = 0; > > > > Can you elaborate why this one above is needed? > > Ah, I removed the comment about it at the last minute. The check below > compares the info we get here with info we got reading the programs in > the earlier loop - using memcmp(). This call, however, doesn't fill in > the pointers for jited and xlated images, so the memcmp() would fail. > > It used to work when bpf_obj_get_info_by_fd() was zeroing info, since > the pointers would be cleared by it, and no dump ever returned, it > didn't matter that the call sites differ.
FWIW the comment was this: + /* Clear the insns pointers, we're not requesting dumps here. + * Otherwise the byte-by-byte comparison below would fail. + */ > > > CHECK(err || info_len != sizeof(struct bpf_prog_info) || > > > memcmp(&prog_info, &prog_infos[i], info_len), > > > "get-prog-info(next_id->fd)", >
