1 files changed, 41 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/kfunc_implicit_args.c b/tools/testing/selftests/bpf/progs/kfunc_implicit_args.c
new file mode 100644
index 000000000000..89b6a47e22dd
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/kfunc_implicit_args.c
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2026 Meta Platforms, Inc. and affiliates. */
+
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+extern int bpf_kfunc_implicit_arg(int a) __weak __ksym;
+extern int bpf_kfunc_implicit_arg_impl(int a, struct bpf_prog_aux *aux) __weak __ksym; /* illegal */
+extern int bpf_kfunc_implicit_arg_legacy(int a, int b) __weak __ksym;
+extern int bpf_kfunc_implicit_arg_legacy_impl(int a, int b, struct bpf_prog_aux *aux) __weak __ksym;
+
+char _license[] SEC("license") = "GPL";
+
+SEC("syscall")
+__retval(5)
+int test_kfunc_implicit_arg(void *ctx)
+{
+	return bpf_kfunc_implicit_arg(5);
+}
+
+SEC("syscall")
+__failure __msg("cannot find address for kernel function bpf_kfunc_implicit_arg_impl")
+int test_kfunc_implicit_arg_impl_illegal(void *ctx)
+{
+	return bpf_kfunc_implicit_arg_impl(5, NULL);
+}
+
+SEC("syscall")
+__retval(7)
+int test_kfunc_implicit_arg_legacy(void *ctx)
+{
+	return bpf_kfunc_implicit_arg_legacy(3, 4);
+}
+
+SEC("syscall")
+__retval(11)
+int test_kfunc_implicit_arg_legacy_impl(void *ctx)
+{
+	return bpf_kfunc_implicit_arg_legacy_impl(5, 6, NULL);
+}