From c446fdacb10dcb3b9a9ed3b91d91e72d71d94b03 Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Tue, 25 Jan 2022 16:13:40 -0800 Subject: [PATCH] bpf: fix register_btf_kfunc_id_set for !CONFIG_DEBUG_INFO_BTF Commit dee872e124e8 ("bpf: Populate kfunc BTF ID sets in struct btf") breaks loading of some modules when CONFIG_DEBUG_INFO_BTF is not set. register_btf_kfunc_id_set returns -ENOENT to the callers when there is no module btf. Let's return 0 (success) instead to let those modules work in !CONFIG_DEBUG_INFO_BTF cases. Acked-by: Kumar Kartikeya Dwivedi Fixes: dee872e124e8 ("bpf: Populate kfunc BTF ID sets in struct btf") Signed-off-by: Stanislav Fomichev Link: https://lore.kernel.org/r/20220126001340.1573649-1-sdf@google.com Signed-off-by: Alexei Starovoitov --- kernel/bpf/btf.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index a1c44c17..b2a2489 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -6740,8 +6740,19 @@ int register_btf_kfunc_id_set(enum bpf_prog_type prog_type, int ret; btf = btf_get_module_btf(kset->owner); - if (IS_ERR_OR_NULL(btf)) - return btf ? PTR_ERR(btf) : -ENOENT; + 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; + } + return 0; + } + if (IS_ERR(btf)) + return PTR_ERR(btf); hook = bpf_prog_type_to_kfunc_hook(prog_type); ret = btf_populate_kfunc_set(btf, hook, kset); -- 2.7.4