The patch titled Subject: kasan: test: improve failure message in KUNIT_EXPECT_KASAN_FAIL() has been removed from the -mm tree. Its filename was kasan-test-improve-failure-message-in-kunit_expect_kasan_fail.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: David Gow <davidgow@xxxxxxxxxx> Subject: kasan: test: improve failure message in KUNIT_EXPECT_KASAN_FAIL() The KUNIT_EXPECT_KASAN_FAIL() macro currently uses KUNIT_EXPECT_EQ() to compare fail_data.report_expected and fail_data.report_found. This always gave a somewhat useless error message on failure, but the addition of extra compile-time checking with READ_ONCE() has caused it to get much longer, and be truncated before anything useful is displayed. Instead, just check fail_data.report_found by hand (we've just set report_expected to 'true'), and print a better failure message with KUNIT_FAIL(). Because of this, report_expected is no longer used anywhere, and can be removed. Beforehand, a failure in: KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)area)[3100]); would have looked like: [22:00:34] [FAILED] vmalloc_oob [22:00:34] # vmalloc_oob: EXPECTATION FAILED at lib/test_kasan.c:991 [22:00:34] Expected ({ do { extern void __compiletime_assert_705(void) __attribute__((__error__("Unsupported access size for {READ,WRITE}_ONCE()."))); if (!((sizeof(fail_data.report_expected) == sizeof(char) || sizeof(fail_data.repp [22:00:34] not ok 45 - vmalloc_oob With this change, it instead looks like: [22:04:04] [FAILED] vmalloc_oob [22:04:04] # vmalloc_oob: EXPECTATION FAILED at lib/test_kasan.c:993 [22:04:04] KASAN failure expected in "((volatile char *)area)[3100]", but none occurred [22:04:04] not ok 45 - vmalloc_oob Also update the example failure in the documentation to reflect this. Link: https://lkml.kernel.org/r/20210606005531.165954-1-davidgow@xxxxxxxxxx Signed-off-by: David Gow <davidgow@xxxxxxxxxx> Reviewed-by: Andrey Konovalov <andreyknvl@xxxxxxxxx> Reviewed-by: Marco Elver <elver@xxxxxxxxxx> Acked-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx> Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Daniel Axtens <dja@xxxxxxxxxx> Cc: David Gow <davidgow@xxxxxxxxxx> Cc: Jonathan Corbet <corbet@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- Documentation/dev-tools/kasan.rst | 9 ++++----- include/linux/kasan.h | 1 - lib/test_kasan.c | 11 +++++------ 3 files changed, 9 insertions(+), 12 deletions(-) --- a/Documentation/dev-tools/kasan.rst~kasan-test-improve-failure-message-in-kunit_expect_kasan_fail +++ a/Documentation/dev-tools/kasan.rst @@ -447,11 +447,10 @@ When a test fails due to a failed ``kmal When a test fails due to a missing KASAN report:: - # kmalloc_double_kzfree: EXPECTATION FAILED at lib/test_kasan.c:629 - Expected kasan_data->report_expected == kasan_data->report_found, but - kasan_data->report_expected == 1 - kasan_data->report_found == 0 - not ok 28 - kmalloc_double_kzfree + # kmalloc_double_kzfree: EXPECTATION FAILED at lib/test_kasan.c:974 + KASAN failure expected in "kfree_sensitive(ptr)", but none occurred + not ok 44 - kmalloc_double_kzfree + At the end the cumulative status of all KASAN tests is printed. On success:: --- a/include/linux/kasan.h~kasan-test-improve-failure-message-in-kunit_expect_kasan_fail +++ a/include/linux/kasan.h @@ -17,7 +17,6 @@ struct task_struct; /* kasan_data struct is used in KUnit tests for KASAN expected failures */ struct kunit_kasan_expectation { - bool report_expected; bool report_found; }; --- a/lib/test_kasan.c~kasan-test-improve-failure-message-in-kunit_expect_kasan_fail +++ a/lib/test_kasan.c @@ -55,7 +55,6 @@ static int kasan_test_init(struct kunit multishot = kasan_save_enable_multi_shot(); kasan_set_tagging_report_once(false); fail_data.report_found = false; - fail_data.report_expected = false; kunit_add_named_resource(test, NULL, NULL, &resource, "kasan_data", &fail_data); return 0; @@ -94,20 +93,20 @@ static void kasan_test_exit(struct kunit !kasan_async_mode_enabled()) \ migrate_disable(); \ KUNIT_EXPECT_FALSE(test, READ_ONCE(fail_data.report_found)); \ - WRITE_ONCE(fail_data.report_expected, true); \ barrier(); \ expression; \ barrier(); \ - KUNIT_EXPECT_EQ(test, \ - READ_ONCE(fail_data.report_expected), \ - READ_ONCE(fail_data.report_found)); \ + if (!READ_ONCE(fail_data.report_found)) { \ + KUNIT_FAIL(test, KUNIT_SUBTEST_INDENT "KASAN failure " \ + "expected in \"" #expression \ + "\", but none occurred"); \ + } \ if (IS_ENABLED(CONFIG_KASAN_HW_TAGS)) { \ if (READ_ONCE(fail_data.report_found)) \ kasan_enable_tagging_sync(); \ migrate_enable(); \ } \ WRITE_ONCE(fail_data.report_found, false); \ - WRITE_ONCE(fail_data.report_expected, false); \ } while (0) #define KASAN_TEST_NEEDS_CONFIG_ON(test, config) do { \ _ Patches currently in -mm which might be from davidgow@xxxxxxxxxx are