[PATCH v6 3/5] init: main: add KUnit to kernel init

[Brendan Higgins <brendanhiggins@xxxxxxxxxx>]

Although we have not seen any actual examples where KUnit doesn't work
because it runs in the late init phase of the kernel, it has been a
concern for some time that this could potentially be an issue in the
future. So, remove KUnit from init calls entirely, instead call directly
from kernel_init() so that KUnit runs after late init.

Co-developed-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
Signed-off-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
Signed-off-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
Reviewed-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Reviewed-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
---
 include/kunit/test.h | 9 +++++++++
 init/main.c          | 4 ++++
 lib/kunit/executor.c | 4 +---
 3 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/include/kunit/test.h b/include/kunit/test.h
index f3e86c3953a2b..795039d9f1917 100644
--- a/include/kunit/test.h
+++ b/include/kunit/test.h
@@ -228,6 +228,15 @@ int __kunit_test_suites_init(struct kunit_suite * const * const suites);
 
 void __kunit_test_suites_exit(struct kunit_suite **suites);
 
+#if IS_BUILTIN(CONFIG_KUNIT)
+int kunit_run_all_tests(void);
+#else
+static inline int kunit_run_all_tests(void)
+{
+	return 0;
+}
+#endif /* IS_BUILTIN(CONFIG_KUNIT) */
+
 /**
  * kunit_test_suites() - used to register one or more &struct kunit_suite
  *			 with KUnit.
diff --git a/init/main.c b/init/main.c
index 0ead83e86b5aa..d3101d8874dea 100644
--- a/init/main.c
+++ b/init/main.c
@@ -106,6 +106,8 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/initcall.h>
 
+#include <kunit/test.h>
+
 static int kernel_init(void *);
 
 extern void init_IRQ(void);
@@ -1504,6 +1506,8 @@ static noinline void __init kernel_init_freeable(void)
 
 	do_basic_setup();
 
+	kunit_run_all_tests();
+
 	console_on_rootfs();
 
 	/*
diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
index 7015e7328dce7..4aab7f70a88c3 100644
--- a/lib/kunit/executor.c
+++ b/lib/kunit/executor.c
@@ -11,7 +11,7 @@ extern struct kunit_suite * const * const __kunit_suites_end[];
 
 #if IS_BUILTIN(CONFIG_KUNIT)
 
-static int kunit_run_all_tests(void)
+int kunit_run_all_tests(void)
 {
 	struct kunit_suite * const * const *suites;
 
@@ -23,6 +23,4 @@ static int kunit_run_all_tests(void)
 	return 0;
 }
 
-late_initcall(kunit_run_all_tests);
-
 #endif /* IS_BUILTIN(CONFIG_KUNIT) */
-- 
2.28.0.163.g6104cc2f0b6-goog