On 23/06/2024 15:35, Alexei Starovoitov wrote: > On Sun, Jun 23, 2024 at 6:52 AM Alan Maguire <alan.maguire@xxxxxxxxxx> wrote: >> >> Kernel test robot reports that kernel build fails with >> resilient split BTF changes. >> >> Examining the associated config and code we see that >> btf_relocate_id() is defined under CONFIG_DEBUG_INFO_BTF_MODULES. >> Moving it outside the #ifdef solves the issue. >> >> Reported-by: kernel test robot <lkp@xxxxxxxxx> >> Closes: https://lore.kernel.org/oe-kbuild-all/202406221742.d2srFLVI-lkp@xxxxxxxxx/ >> Signed-off-by: Alan Maguire <alan.maguire@xxxxxxxxxx> >> --- >> kernel/bpf/btf.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c >> index 8e12cb80ba73..4ff11779699e 100644 >> --- a/kernel/bpf/btf.c >> +++ b/kernel/bpf/btf.c >> @@ -6185,8 +6185,6 @@ struct btf *btf_parse_vmlinux(void) >> return btf; >> } >> >> -#ifdef CONFIG_DEBUG_INFO_BTF_MODULES >> - >> /* If .BTF_ids section was created with distilled base BTF, both base and >> * split BTF ids will need to be mapped to actual base/split ids for >> * BTF now that it has been relocated. >> @@ -6198,6 +6196,8 @@ static __u32 btf_relocate_id(const struct btf *btf, __u32 id) >> return btf->base_id_map[id]; >> } >> >> +#ifdef CONFIG_DEBUG_INFO_BTF_MODULES >> + > > It doesn't fix it all. The 32 build is still failing: > > ../kernel/bpf/btf.c: In function ‘btf_populate_kfunc_set’: > -../kernel/bpf/btf.c:8251:36: error: implicit declaration of function > ‘btf_relocate_id’; did you mean ‘btf_relocate’? > [-Wimplicit-function-declaration] > - 8251 | set->pairs[i].id = btf_relocate_id(btf, > set->pairs[i].id); > - | ^~~~~~~~~~~~~~~ > - | btf_relocate > - > > See build_32, build_clang, build_allmod failures in CI: > https://patchwork.kernel.org/project/netdevbpf/patch/20240623135224.27981-1-alan.maguire@xxxxxxxxxx/ I've been trying to reproduce this with no success I'm afraid. I may be misreading but it appears that the diff from baseline to new build is actually telling us the btf_relocate_id() issues went away https://netdev.bots.linux.dev/static/nipa/864622/13708618/build_clang/stderr shows (note the "-" in the diffs preceding the btf_relocate_id() complaints): New errors added --- /tmp/tmp.tLVKGCnz0N 2024-06-23 07:09:50.097720906 -0700 +++ /tmp/tmp.5jUDaRbbAY 2024-06-23 07:10:36.751715396 -0700 @@ -9,24 +9,846 @@ -../kernel/bpf/btf.c:8251:22: error: call to undeclared function 'btf_relocate_id'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration] - 8251 | set->pairs[i].id = btf_relocate_id(btf, set->pairs[i].id); - | ^ -../kernel/bpf/btf.c:8251:22: note: did you mean 'btf_relocate'? -../include/linux/btf.h:556:5: note: 'btf_relocate' declared here - 556 | int btf_relocate(struct btf *btf, const struct btf *base_btf, __u32 **map_ids); - | ^ -../kernel/bpf/btf.c:8376:37: error: call to undeclared function 'btf_relocate_id'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration] - 8376 | ret = btf_check_kfunc_protos(btf, btf_relocate_id(btf, kset->set->pairs[i].id), - | ^ -../kernel/bpf/btf.c:8440:17: error: call to undeclared function 'btf_relocate_id'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration] - 8440 | dtor_btf_id = btf_relocate_id(btf, dtors[i].kfunc_btf_id); - | ^ -../kernel/bpf/btf.c:8529:26: error: call to undeclared function 'btf_relocate_id'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration] - 8529 | tab->dtors[i].btf_id = btf_relocate_id(btf, tab->dtors[i].btf_id); - | ^ -4 errors generated. -make[5]: *** [../kernel/bpf/Makefile:60: kernel/bpf/btf.o] Error 1 -make[4]: *** [../scripts/Makefile.build:485: kernel/bpf] Error 2 -make[3]: *** [../scripts/Makefile.build:485: kernel] Error 2 -make[3]: *** Waiting for unfinished jobs.... -make[2]: *** [/home/nipa/bpf-next/wt-0/Makefile:1934: .] Error 2 -make[1]: *** [/home/nipa/bpf-next/wt-0/Makefile:240: __sub-make] Error 2 -make: *** [Makefile:240: __sub-make] Error 2 +WARNING: modpost: missing MODULE_DESCRIPTION() in vmlinux.o +WARNING: modpost: missing MODULE_DESCRIPTION() in arch/x86/kernel/cpu/mce/mce-inject.o +WARNING: modpost: missing MODULE_DESCRIPTION() in arch/x86/mm/testmmiotrace.o +WARNING: modpost: missing MODULE_DESCRIPTION() in arch/x86/crypto/crc32-pclmul.o +WARNING: modpost: missing MODULE_DESCRIPTION() in arch/x86/crypto/curve25519-x86_64.o ... ...and looking at https://github.com/linux-netdev/nipa/blob/main/tests/patch/build_32bit/build_32bit.sh ...that appears to be a diff between old and new build logs. The new issues all appear to be missing module license complaints in an allmodconfig build. I did find another issue in tools/lib/bpf/btf_relocate.c when compiling with clang that I'll send a patch for, and there's an existing issue in btf.c that generates a warning: tools/testing/selftests/kvm/settings: warning: ignored by one of the .gitignore files ../kernel/bpf/btf.c: In function ‘btf_seq_show’: ../kernel/bpf/btf.c:7544:29: warning: function ‘btf_seq_show’ might be a candidate for ‘gnu_printf’ format attribute [-Wsuggest-attribute=format] 7544 | seq_vprintf((struct seq_file *)show->target, fmt, args); | ^~~~~~~~ ../kernel/bpf/btf.c: In function ‘btf_snprintf_show’: ../kernel/bpf/btf.c:7581:9: warning: function ‘btf_snprintf_show’ might be a candidate for ‘gnu_printf’ format attribute [-Wsuggest-attribute=format] 7581 | len = vsnprintf(show->target, ssnprintf->len_left, fmt, args); | ^~~ ...but I can't see how this fix is still causing failures in finding btf_relocate_id(). There may be something I'm missing here of course. Thanks! Alan
