[v7,08/10] selftests/harness: Share _metadata between forked processes

Commit Message

Mickaël Salaün May 11, 2024, 5:14 p.m. UTC

Unconditionally share _metadata between all forked processes, which
enables to actually catch errors which were previously ignored.

This is required for a following commit replacing vfork() with clone3()
and CLONE_VFORK (i.e. not sharing the full memory) .  It should also be
useful to share _metadata to extend expectations to test process's
forks.  For instance, this change identified a wrong expectation in
pidfd_setns_test.

Because this _metadata is used by the new XFAIL_ADD(), use a global
pointer initialized in TEST_F().  This is OK because only XFAIL_ADD()
use it, and XFAIL_ADD() already depends on TEST_F().

Cc: Jakub Kicinski <[e-mail]>
Cc: Shuah Khan <[e-mail]>
Cc: Will Drewry <[e-mail]>
Reviewed-by: Kees Cook <[e-mail]>
Signed-off-by: Mickaël Salaün <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
---

Changes since v6:
* Use a global pointer per TEST_F() and complete build of the
  __test_xfail object in the xfail constructor to fix XFAIL_ADD():
  https://lore.kernel.org/r/[e-mail]/

Changes since v4:
* Reset _metadata's aborted and setup_completed fields.

Changes since v1:
* Extract change from a bigger patch (suggested by Kees).
---
 tools/testing/selftests/kselftest_harness.h | 26 ++++++++++++---------
 1 file changed, 15 insertions(+), 11 deletions(-)

Patch

diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index 201040207c85..28415798fa60 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -430,19 +430,19 @@  static inline pid_t clone3_vfork(void)
 			kill(getpid(), WTERMSIG(status)); \
 		__test_check_assert(_metadata); \
 	} \
-	static struct __test_metadata \
-		      _##fixture_name##_##test_name##_object = { \
-		.name = #test_name, \
-		.fn = &wrapper_##fixture_name##_##test_name, \
-		.fixture = &_##fixture_name##_fixture_object, \
-		.termsig = signal, \
-		.timeout = tmout, \
-		.teardown_parent = false, \
-	 }; \
+	static struct __test_metadata *_##fixture_name##_##test_name##_object; \
 	static void __attribute__((constructor)) \
 			_register_##fixture_name##_##test_name(void) \
 	{ \
-		__register_test(&_##fixture_name##_##test_name##_object); \
+		struct __test_metadata *object = mmap(NULL, sizeof(*object), \
+			PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0); \
+		object->name = #test_name; \
+		object->fn = &wrapper_##fixture_name##_##test_name; \
+		object->fixture = &_##fixture_name##_fixture_object; \
+		object->termsig = signal; \
+		object->timeout = tmout; \
+		_##fixture_name##_##test_name##_object = object; \
+		__register_test(object); \
 	} \
 	static void fixture_name##_##test_name( \
 		struct __test_metadata __attribute__((unused)) *_metadata, \
@@ -850,11 +850,12 @@  struct __test_xfail {
 	{ \
 		.fixture = &_##fixture_name##_fixture_object, \
 		.variant = &_##fixture_name##_##variant_name##_object, \
-		.test = &_##fixture_name##_##test_name##_object, \
 	}; \
 	static void __attribute__((constructor)) \
 		_register_##fixture_name##_##variant_name##_##test_name##_xfail(void) \
 	{ \
+		_##fixture_name##_##variant_name##_##test_name##_xfail.test = \
+			_##fixture_name##_##test_name##_object; \
 		__register_xfail(&_##fixture_name##_##variant_name##_##test_name##_xfail); \
 	}
 
@@ -1181,6 +1182,9 @@  void __run_test(struct __fixture_metadata *f,
 	/* reset test struct */
 	t->exit_code = KSFT_PASS;
 	t->trigger = 0;
+	t->aborted = false;
+	t->setup_completed = false;
+	memset(t->env, 0, sizeof(t->env));
 	memset(t->results->reason, 0, sizeof(t->results->reason));
 
 	if (asprintf(&test_name, "%s%s%s.%s", f->name,