[PATCH v2 09/11] kunit: uapi: Add example for UAPI tests

["Thomas Weißschuh" <thomas.weissschuh@linutronix.de>]

Extend the example to show how to run a userspace executable.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
 lib/kunit/.kunitconfig         |  2 ++
 lib/kunit/Makefile             |  9 ++++++++-
 lib/kunit/kunit-example-test.c | 15 +++++++++++++++
 lib/kunit/kunit-example-uapi.c | 22 ++++++++++++++++++++++
 4 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/lib/kunit/.kunitconfig b/lib/kunit/.kunitconfig
index 9235b7d42d389d2c7bf912546c7bb084eae99235..b7433e691563a3a8442db69874dea88f3b607332 100644
--- a/lib/kunit/.kunitconfig
+++ b/lib/kunit/.kunitconfig
@@ -1,3 +1,5 @@
 CONFIG_KUNIT=y
+CONFIG_SHMEM=y
+CONFIG_TMPFS=y
 CONFIG_KUNIT_TEST=y
 CONFIG_KUNIT_EXAMPLE_TEST=y
diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile
index 989933dab9ad2267f376db470b876ce2a88711b4..1b6be12676f89cafa34f0093d8136b36f4cf5532 100644
--- a/lib/kunit/Makefile
+++ b/lib/kunit/Makefile
@@ -30,4 +30,11 @@ obj-$(CONFIG_KUNIT_TEST) +=		string-stream-test.o
 obj-$(CONFIG_KUNIT_TEST) +=		assert_test.o
 endif
 
-obj-$(CONFIG_KUNIT_EXAMPLE_TEST) +=	kunit-example-test.o
+userprogs +=				kunit-example-uapi
+kunit-example-uapi-userccflags :=	-static
+kunit-example-uapi-nolibc :=		$(CONFIG_ARCH_HAS_NOLIBC)
+blobs +=				kunit-example-uapi.blob.o
+
+obj-$(CONFIG_KUNIT_EXAMPLE_TEST) +=	kunit-example-mod.o
+kunit-example-mod-y +=			kunit-example-test.o
+kunit-example-mod-$(CONFIG_KUNIT_UAPI) += kunit-example-uapi.blob.o
diff --git a/lib/kunit/kunit-example-test.c b/lib/kunit/kunit-example-test.c
index 3056d6bc705d0a8f196f0f4412e679dbb0e03114..b2681a6e047dfd6fea4a7cca60e81651d09c2eae 100644
--- a/lib/kunit/kunit-example-test.c
+++ b/lib/kunit/kunit-example-test.c
@@ -6,8 +6,11 @@
  * Author: Brendan Higgins <brendanhiggins@google.com>
  */
 
+#include <linux/blob.h>
+
 #include <kunit/test.h>
 #include <kunit/static_stub.h>
+#include <kunit/uapi.h>
 
 /*
  * This is the most fundamental element of KUnit, the test case. A test case
@@ -277,6 +280,17 @@ static void example_slow_test(struct kunit *test)
 	KUNIT_EXPECT_EQ(test, 1 + 1, 2);
 }
 
+/*
+ * This test shows the usage of UAPI tests.
+ */
+static void example_uapi_test(struct kunit *test)
+{
+	if (IS_ENABLED(CONFIG_KUNIT_UAPI))
+		kunit_uapi_run_kselftest(test, BLOB(kunit_example_uapi));
+	else
+		kunit_skip(test, "CONFIG_KUNIT_UAPI is not enabled");
+}
+
 /*
  * Here we make a list of all the test cases we want to add to the test suite
  * below.
@@ -297,6 +311,7 @@ static struct kunit_case example_test_cases[] = {
 	KUNIT_CASE(example_priv_test),
 	KUNIT_CASE_PARAM(example_params_test, example_gen_params),
 	KUNIT_CASE_SLOW(example_slow_test),
+	KUNIT_CASE(example_uapi_test),
 	{}
 };
 
diff --git a/lib/kunit/kunit-example-uapi.c b/lib/kunit/kunit-example-uapi.c
new file mode 100644
index 0000000000000000000000000000000000000000..4ce657050dd4a576632a41ca0309c4cb5134ce14
--- /dev/null
+++ b/lib/kunit/kunit-example-uapi.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit Userspace example test.
+ *
+ * Copyright (C) 2025, Linutronix GmbH.
+ * Author: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
+ *
+ * This is *userspace* code.
+ */
+
+#include "../../tools/testing/selftests/kselftest.h"
+
+int main(void)
+{
+	ksft_print_header();
+	ksft_set_plan(4);
+	ksft_test_result_pass("userspace test 1\n");
+	ksft_test_result_pass("userspace test 2\n");
+	ksft_test_result_skip("userspace test 3: some reason\n");
+	ksft_test_result_pass("userspace test 4\n");
+	ksft_finished();
+}

-- 
2.49.0