Show the precise rejected function name when attaching tracing to
__btf_id functions.
$ ./fentry
libbpf: prog 'migrate_disable': BPF program load failed: -EINVAL
libbpf: prog 'migrate_disable': -- BEGIN PROG LOAD LOG --
Attaching tracing to __btf_id function 'migrate_disable' is rejected.
Signed-off-by: KaFai Wan <mannkafai@xxxxxxxxx>
---
kernel/bpf/verifier.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 275d82fb1a1a..2779d63e1f8b 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -23938,6 +23938,8 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
return ret;
} else if (prog->type == BPF_PROG_TYPE_TRACING &&
btf_id_set_contains(&btf_id_deny, btf_id)) {
+ verbose(env, "Attaching tracing to __btf_id function '%s' is rejected.\n",
+ tgt_info.tgt_name);
return -EINVAL;
} else if ((prog->expected_attach_type == BPF_TRACE_FEXIT ||
prog->expected_attach_type == BPF_MODIFY_RETURN) &&
--
2.43.0
