[PATCH bpf-next v2 09/15] selftests/bpf: verify struct_ops autoload/autocreate sync

[Eduard Zingerman <eddyz87@xxxxxxxxx>]

Check that autocreate flag set to false for struct_ops map causes
autoload flag set to false for corresponding program.

Check that struct_ops program not referenced from any map fails to load.

Signed-off-by: Eduard Zingerman <eddyz87@xxxxxxxxx>
---
 .../selftests/bpf/prog_tests/bad_struct_ops.c | 32 +++++++++++++++++++
 .../bpf/prog_tests/struct_ops_autocreate.c    | 11 ++++---
 .../selftests/bpf/progs/bad_struct_ops2.c     | 14 ++++++++
 3 files changed, 52 insertions(+), 5 deletions(-)
 create mode 100644 tools/testing/selftests/bpf/progs/bad_struct_ops2.c

diff --git a/tools/testing/selftests/bpf/prog_tests/bad_struct_ops.c b/tools/testing/selftests/bpf/prog_tests/bad_struct_ops.c
index 9f5dbefa0dd9..6a707213e46b 100644
--- a/tools/testing/selftests/bpf/prog_tests/bad_struct_ops.c
+++ b/tools/testing/selftests/bpf/prog_tests/bad_struct_ops.c
@@ -2,6 +2,7 @@
 
 #include <test_progs.h>
 #include "bad_struct_ops.skel.h"
+#include "bad_struct_ops2.skel.h"
 
 static void invalid_prog_reuse(void)
 {
@@ -28,8 +29,39 @@ static void invalid_prog_reuse(void)
 	bad_struct_ops__destroy(skel);
 }
 
+static void unused_program(void)
+{
+	struct bad_struct_ops2 *skel;
+	char *log = NULL;
+	int err;
+
+	skel = bad_struct_ops2__open();
+	if (!ASSERT_OK_PTR(skel, "bad_struct_ops2__open"))
+		return;
+
+	/* struct_ops programs not referenced from any maps are open
+	 * with autoload set to true.
+	 */
+	ASSERT_TRUE(bpf_program__autoload(skel->progs.foo), "foo autoload == true");
+
+	if (start_libbpf_log_capture())
+		goto cleanup;
+
+	err = bad_struct_ops2__load(skel);
+	ASSERT_ERR(err, "bad_struct_ops2__load should fail");
+	log = stop_libbpf_log_capture();
+	ASSERT_HAS_SUBSTR(log, "prog 'foo': failed to load",
+			  "message about 'foo' failing to load");
+
+cleanup:
+	free(log);
+	bad_struct_ops2__destroy(skel);
+}
+
 void test_bad_struct_ops(void)
 {
 	if (test__start_subtest("invalid_prog_reuse"))
 		invalid_prog_reuse();
+	if (test__start_subtest("unused_program"))
+		unused_program();
 }
diff --git a/tools/testing/selftests/bpf/prog_tests/struct_ops_autocreate.c b/tools/testing/selftests/bpf/prog_tests/struct_ops_autocreate.c
index c67d0b32b9dc..765b0ec6383a 100644
--- a/tools/testing/selftests/bpf/prog_tests/struct_ops_autocreate.c
+++ b/tools/testing/selftests/bpf/prog_tests/struct_ops_autocreate.c
@@ -35,18 +35,19 @@ static void cant_load_full_object(void)
 
 static void can_load_partial_object(void)
 {
-	LIBBPF_OPTS(bpf_object_open_opts, opts);
 	struct struct_ops_autocreate *skel;
 	struct bpf_link *link = NULL;
 	int err;
 
-	skel = struct_ops_autocreate__open_opts(&opts);
+	skel = struct_ops_autocreate__open();
 	if (!ASSERT_OK_PTR(skel, "struct_ops_autocreate__open_opts"))
 		return;
 
-	err = bpf_program__set_autoload(skel->progs.test_2, false);
-	if (!ASSERT_OK(err, "bpf_program__set_autoload"))
-		goto cleanup;
+	/* struct_ops programs referenced from maps are open with
+	 * autoload set to false.
+	 */
+	ASSERT_FALSE(bpf_program__autoload(skel->progs.test_1), "test_1 autoload == false");
+	ASSERT_FALSE(bpf_program__autoload(skel->progs.test_2), "test_2 autoload == false");
 
 	err = bpf_map__set_autocreate(skel->maps.testmod_2, false);
 	if (!ASSERT_OK(err, "bpf_map__set_autocreate"))
diff --git a/tools/testing/selftests/bpf/progs/bad_struct_ops2.c b/tools/testing/selftests/bpf/progs/bad_struct_ops2.c
new file mode 100644
index 000000000000..64a95f6be86d
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/bad_struct_ops2.c
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+char _license[] SEC("license") = "GPL";
+
+/* This is an unused struct_ops program, it lacks corresponding
+ * struct_ops map, which provides attachment information.
+ * W/o additional configuration attempt to load such
+ * BPF object file would fail.
+ */
+SEC("struct_ops/foo")
+void foo(void) {}
-- 
2.43.0