On 3/24/25 11:07 AM, Ihor Solodrai wrote: > On 3/23/25 4:11 AM, Alan Maguire wrote: >> [...] >> >> hi Ihor, I took a look at the series and merged it with latest next >> branch; results are in >> >> https://web.git.kernel.org/pub/scm/devel/pahole/pahole.git/log/?h=next.attributes-v4 >> >> ...if you want to take a look. >> >> There are a few small things I think that it would be good to resolve >> before landing this. >> >> First, when testing this with -DLIBBPF_EMBEDDED=OFF and a packaged >> libbpf 1.5 - which means we wouldn't have the latest attributes-related >> libbpf function; I saw: >> >> BTF .tmp_vmlinux1.btf.o >> btf__add_type_attr is not available, is libbpf < 1.6? >> error: failed to encode function 'bbr_cwnd_event': invalid proto >> Failed to encode BTF >> NM .tmp_vmlinux1.syms > > Hi Alan. Thanks for testing. This is my mistake, I should've checked > for attributes feature here: > > @@ -731,6 +812,10 @@ static int32_t btf_encoder__add_func_proto(struct btf_encoder *encoder, struct f > > assert(ftype != NULL || state != NULL); > > + if (is_kfunc_state(state) && encoder->tag_kfuncs) > + if (btf__add_bpf_arena_type_tags(encoder->btf, state) < 0) > + return -1; Actually, I added this check in a different patch so the failure must have happened in a different place. In any case, the point remains that it's better to check for feature availability (hence for API availability) in one place. Your suggestion to add a feature check makes sense to me. Thank you. > [...]
