From 7fa46cdfffd29459f9ebf6ed891a4c721db06a33 Mon Sep 17 00:00:00 2001 From: Harry Yoo Date: Tue, 18 Mar 2025 10:59:26 +0900 Subject: [PATCH] mm/kasan: use SLAB_NO_MERGE flag instead of an empty constructor Use SLAB_NO_MERGE flag to prevent merging instead of providing an empty constructor. Using an empty constructor in this manner is an abuse of slab interface. The SLAB_NO_MERGE flag should be used with caution, but in this case, it is acceptable as the cache is intended solely for debugging purposes. No functional changes intended. Link: https://lkml.kernel.org/r/20250318015926.1629748-1-harry.yoo@oracle.com Signed-off-by: Harry Yoo Reviewed-by: Alexander Potapenko Reviewed-by: Andrey Konovalov Acked-by: Andrey Ryabinin Cc: Dmitriy Vyukov Cc: Vincenzo Frascino Signed-off-by: Andrew Morton --- mm/kasan/kasan_test_c.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/mm/kasan/kasan_test_c.c b/mm/kasan/kasan_test_c.c index 59d673400085..3ea317837c2d 100644 --- a/mm/kasan/kasan_test_c.c +++ b/mm/kasan/kasan_test_c.c @@ -1073,14 +1073,11 @@ static void kmem_cache_rcu_uaf(struct kunit *test) kmem_cache_destroy(cache); } -static void empty_cache_ctor(void *object) { } - static void kmem_cache_double_destroy(struct kunit *test) { struct kmem_cache *cache; - /* Provide a constructor to prevent cache merging. */ - cache = kmem_cache_create("test_cache", 200, 0, 0, empty_cache_ctor); + cache = kmem_cache_create("test_cache", 200, 0, SLAB_NO_MERGE, NULL); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); kmem_cache_destroy(cache); KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_destroy(cache)); -- 2.50.1