Re: [PATCH 03/14] kunit: Add test cases for backtrace warning suppression

2024-03-12 Thread Kees Cook
On Tue, Mar 12, 2024 at 10:02:58AM -0700, Guenter Roeck wrote:
> Add unit tests to verify that warning backtrace suppression works.
> 
> If backtrace suppression does _not_ work, the unit tests will likely
> trigger unsuppressed backtraces, which should actually help to get
> the affected architectures / platforms fixed.
> 
> Signed-off-by: Guenter Roeck 

Reviewed-by: Kees Cook 

-- 
Kees Cook


[PATCH 03/14] kunit: Add test cases for backtrace warning suppression

2024-03-12 Thread Guenter Roeck
Add unit tests to verify that warning backtrace suppression works.

If backtrace suppression does _not_ work, the unit tests will likely
trigger unsuppressed backtraces, which should actually help to get
the affected architectures / platforms fixed.

Signed-off-by: Guenter Roeck 
---
 lib/kunit/Makefile |   3 +-
 lib/kunit/backtrace-suppression-test.c | 104 +
 2 files changed, 106 insertions(+), 1 deletion(-)
 create mode 100644 lib/kunit/backtrace-suppression-test.c

diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile
index 545b57c3be48..6a44d2b54ea9 100644
--- a/lib/kunit/Makefile
+++ b/lib/kunit/Makefile
@@ -19,7 +19,8 @@ endif
 obj-y +=   hooks.o \
bug.o
 
-obj-$(CONFIG_KUNIT_TEST) +=kunit-test.o
+obj-$(CONFIG_KUNIT_TEST) +=kunit-test.o \
+   backtrace-suppression-test.o
 
 # string-stream-test compiles built-in only.
 ifeq ($(CONFIG_KUNIT_TEST),y)
diff --git a/lib/kunit/backtrace-suppression-test.c 
b/lib/kunit/backtrace-suppression-test.c
new file mode 100644
index ..47c619283802
--- /dev/null
+++ b/lib/kunit/backtrace-suppression-test.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit test for suppressing warning tracebacks
+ *
+ * Copyright (C) 2024, Guenter Roeck
+ * Author: Guenter Roeck 
+ */
+
+#include 
+#include 
+
+static void backtrace_suppression_test_warn_direct(struct kunit *test)
+{
+   DEFINE_SUPPRESSED_WARNING(backtrace_suppression_test_warn_direct);
+
+   START_SUPPRESSED_WARNING(backtrace_suppression_test_warn_direct);
+   WARN(1, "This backtrace should be suppressed");
+   END_SUPPRESSED_WARNING(backtrace_suppression_test_warn_direct);
+
+   KUNIT_EXPECT_EQ(test, 
SUPPRESSED_WARNING_COUNT(backtrace_suppression_test_warn_direct), 1);
+}
+
+static void trigger_backtrace_warn(void)
+{
+   WARN(1, "This backtrace should be suppressed");
+}
+
+static void backtrace_suppression_test_warn_indirect(struct kunit *test)
+{
+   DEFINE_SUPPRESSED_WARNING(trigger_backtrace_warn);
+
+   START_SUPPRESSED_WARNING(trigger_backtrace_warn);
+   trigger_backtrace_warn();
+   END_SUPPRESSED_WARNING(trigger_backtrace_warn);
+
+   KUNIT_EXPECT_EQ(test, SUPPRESSED_WARNING_COUNT(trigger_backtrace_warn), 
1);
+}
+
+static void backtrace_suppression_test_warn_multi(struct kunit *test)
+{
+   DEFINE_SUPPRESSED_WARNING(trigger_backtrace_warn);
+   DEFINE_SUPPRESSED_WARNING(backtrace_suppression_test_warn_multi);
+
+   START_SUPPRESSED_WARNING(backtrace_suppression_test_warn_multi);
+   START_SUPPRESSED_WARNING(trigger_backtrace_warn);
+   WARN(1, "This backtrace should be suppressed");
+   trigger_backtrace_warn();
+   END_SUPPRESSED_WARNING(trigger_backtrace_warn);
+   END_SUPPRESSED_WARNING(backtrace_suppression_test_warn_multi);
+
+   KUNIT_EXPECT_EQ(test, 
SUPPRESSED_WARNING_COUNT(backtrace_suppression_test_warn_multi), 1);
+   KUNIT_EXPECT_EQ(test, SUPPRESSED_WARNING_COUNT(trigger_backtrace_warn), 
1);
+}
+
+static void backtrace_suppression_test_warn_on_direct(struct kunit *test)
+{
+   DEFINE_SUPPRESSED_WARNING(backtrace_suppression_test_warn_on_direct);
+
+   if (!IS_ENABLED(CONFIG_DEBUG_BUGVERBOSE) && 
!IS_ENABLED(CONFIG_KALLSYMS))
+   kunit_skip(test, "requires CONFIG_DEBUG_BUGVERBOSE or 
CONFIG_KALLSYMS");
+
+   START_SUPPRESSED_WARNING(backtrace_suppression_test_warn_on_direct);
+   WARN_ON(1);
+   END_SUPPRESSED_WARNING(backtrace_suppression_test_warn_on_direct);
+
+   KUNIT_EXPECT_EQ(test,
+   
SUPPRESSED_WARNING_COUNT(backtrace_suppression_test_warn_on_direct), 1);
+}
+
+static void trigger_backtrace_warn_on(void)
+{
+   WARN_ON(1);
+}
+
+static void backtrace_suppression_test_warn_on_indirect(struct kunit *test)
+{
+   DEFINE_SUPPRESSED_WARNING(trigger_backtrace_warn_on);
+
+   if (!IS_ENABLED(CONFIG_DEBUG_BUGVERBOSE))
+   kunit_skip(test, "requires CONFIG_DEBUG_BUGVERBOSE");
+
+   START_SUPPRESSED_WARNING(trigger_backtrace_warn_on);
+   trigger_backtrace_warn_on();
+   END_SUPPRESSED_WARNING(trigger_backtrace_warn_on);
+
+   KUNIT_EXPECT_EQ(test, 
SUPPRESSED_WARNING_COUNT(trigger_backtrace_warn_on), 1);
+}
+
+static struct kunit_case backtrace_suppression_test_cases[] = {
+   KUNIT_CASE(backtrace_suppression_test_warn_direct),
+   KUNIT_CASE(backtrace_suppression_test_warn_indirect),
+   KUNIT_CASE(backtrace_suppression_test_warn_multi),
+   KUNIT_CASE(backtrace_suppression_test_warn_on_direct),
+   KUNIT_CASE(backtrace_suppression_test_warn_on_indirect),
+   {}
+};
+
+static struct kunit_suite backtrace_suppression_test_suite = {
+   .name = "backtrace-suppression-test",
+   .test_cases = backtrace_suppression_test_cases,
+};
+kunit_test_suites(&backtrace_suppression_test_suite);
+
+