bpf: improve error message for unsupported helper

BPF verifier emits "unknown func" message when given BPF program type does not support BPF helper. This message may be confusing for users, as important context that helper is unknown only to current program type is not provided. This patch changes message to "program of this type cannot use helper " and aligns dependent code in libbpf and tests. Any suggestions on improving/changing this message are welcome. Signed-off-by: Mykyta Yatsenko <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Acked-by: Quentin Monnet <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>
libbpf · Apr 2, 2024 · 9a40292 · 9a40292
1 parent 91360ab
commit 9a40292
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/src/feature.c b/src/feature.c
@@ -664,7 +664,8 @@ probe_helper_ifindex(enum bpf_func_id id, enum bpf_prog_type prog_type,
 
 	probe_prog_load_ifindex(prog_type, insns, ARRAY_SIZE(insns), buf,
 				sizeof(buf), ifindex);
-	res = !grep(buf, "invalid func ") && !grep(buf, "unknown func ");
+	res = !grep(buf, "invalid func ") && !grep(buf, "unknown func ") &&
+		!grep(buf, "program of this type cannot use helper ");
 
 	switch (get_vendor_id(ifindex)) {
 	case 0x19ee: /* Netronome specific */