On Mon, Jun 26, 2023 at 06:11:20PM +0000, SeongJae Park wrote: > __register_btf_kfunc_id_set() assumes .BTF to be part of the module's > .ko file if CONFIG_DEBUG_INFO_BTF is enabled. If that's not the case, > the function prints an error message and return an error. As a result, > such modules cannot be loaded. > > However, the section could be stripped out during a build process. It > would be better to let the modules loaded, because their basic > functionalities have no problem[1], though the BTF functionalities will > not be supported. Make the function to lower the level of the message > from error to warn, and return no error. > > [1] https://lore.kernel.org/bpf/20220219082037.ow2kbq5brktf4f2u@apollo.legion/ > > Reported-by: Alexander Egorenkov <Alexander.Egorenkov@xxxxxxx> > Link: https://lore.kernel.org/bpf/87y228q66f.fsf@xxxxxxxxxxxxxxxxxxxx/ > Suggested-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx> > Link: https://lore.kernel.org/bpf/20220219082037.ow2kbq5brktf4f2u@apollo.legion/ > Fixes: dee872e124e8 ("bpf: Populate kfunc BTF ID sets in struct btf") should it be this one in Fixes instead? c446fdacb10d bpf: fix register_btf_kfunc_id_set for !CONFIG_DEBUG_INFO_BTF other than that looks good Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx> jirka > Cc: <stable@xxxxxxxxxxxxxxx> # 5.17.x > Signed-off-by: SeongJae Park <sj@xxxxxxxxxx> > --- > kernel/bpf/btf.c | 12 ++++-------- > 1 file changed, 4 insertions(+), 8 deletions(-) > > diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c > index 6b682b8e4b50..d683f034996f 100644 > --- a/kernel/bpf/btf.c > +++ b/kernel/bpf/btf.c > @@ -7848,14 +7848,10 @@ static int __register_btf_kfunc_id_set(enum btf_kfunc_hook hook, > > btf = btf_get_module_btf(kset->owner); > if (!btf) { > - if (!kset->owner && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) { > - pr_err("missing vmlinux BTF, cannot register kfuncs\n"); > - return -ENOENT; > - } > - if (kset->owner && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES)) { > - pr_err("missing module BTF, cannot register kfuncs\n"); > - return -ENOENT; > - } > + if (!kset->owner && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) > + pr_warn("missing vmlinux BTF, cannot register kfuncs\n"); > + if (kset->owner && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES)) > + pr_warn("missing module BTF, cannot register kfuncs\n"); > return 0; > } > if (IS_ERR(btf)) > -- > 2.25.1 > >
