From a285909f471d6703a04b2b3942c352e27131c92b Mon Sep 17 00:00:00 2001 From: Hyeonggon Yoo <42.hyeyoo@gmail.com> Date: Wed, 6 Apr 2022 15:00:03 +0900 Subject: [PATCH] mm/slub, kunit: Make slub_kunit unaffected by user specified flags slub_kunit does not expect other debugging flags to be set when running tests. When SLAB_RED_ZONE flag is set globally, test fails because the flag affects number of errors reported. To make slub_kunit unaffected by user specified debugging flags, introduce SLAB_NO_USER_FLAGS to ignore them. With this flag, only flags specified in the code are used and others are ignored. Suggested-by: Vlastimil Babka Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka Link: https://lore.kernel.org/r/Yk0sY9yoJhFEXWOg@hyeyoo --- include/linux/slab.h | 7 +++++++ lib/slub_kunit.c | 10 +++++----- mm/slab.h | 5 +++-- mm/slub.c | 3 +++ 4 files changed, 18 insertions(+), 7 deletions(-) diff --git a/include/linux/slab.h b/include/linux/slab.h index 373b3ef99f4e..11ceddcae9f4 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -112,6 +112,13 @@ #define SLAB_KASAN 0 #endif +/* + * Ignore user specified debugging flags. + * Intended for caches created for self-tests so they have only flags + * specified in the code and other flags are ignored. + */ +#define SLAB_NO_USER_FLAGS ((slab_flags_t __force)0x10000000U) + /* The following flags affect the page allocator grouping pages by mobility */ /* Objects are reclaimable */ #define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U) diff --git a/lib/slub_kunit.c b/lib/slub_kunit.c index 8662dc6cb509..7a0564d7cb7a 100644 --- a/lib/slub_kunit.c +++ b/lib/slub_kunit.c @@ -12,7 +12,7 @@ static int slab_errors; static void test_clobber_zone(struct kunit *test) { struct kmem_cache *s = kmem_cache_create("TestSlub_RZ_alloc", 64, 0, - SLAB_RED_ZONE, NULL); + SLAB_RED_ZONE|SLAB_NO_USER_FLAGS, NULL); u8 *p = kmem_cache_alloc(s, GFP_KERNEL); kasan_disable_current(); @@ -30,7 +30,7 @@ static void test_clobber_zone(struct kunit *test) static void test_next_pointer(struct kunit *test) { struct kmem_cache *s = kmem_cache_create("TestSlub_next_ptr_free", 64, 0, - SLAB_POISON, NULL); + SLAB_POISON|SLAB_NO_USER_FLAGS, NULL); u8 *p = kmem_cache_alloc(s, GFP_KERNEL); unsigned long tmp; unsigned long *ptr_addr; @@ -75,7 +75,7 @@ static void test_next_pointer(struct kunit *test) static void test_first_word(struct kunit *test) { struct kmem_cache *s = kmem_cache_create("TestSlub_1th_word_free", 64, 0, - SLAB_POISON, NULL); + SLAB_POISON|SLAB_NO_USER_FLAGS, NULL); u8 *p = kmem_cache_alloc(s, GFP_KERNEL); kmem_cache_free(s, p); @@ -90,7 +90,7 @@ static void test_first_word(struct kunit *test) static void test_clobber_50th_byte(struct kunit *test) { struct kmem_cache *s = kmem_cache_create("TestSlub_50th_word_free", 64, 0, - SLAB_POISON, NULL); + SLAB_POISON|SLAB_NO_USER_FLAGS, NULL); u8 *p = kmem_cache_alloc(s, GFP_KERNEL); kmem_cache_free(s, p); @@ -106,7 +106,7 @@ static void test_clobber_50th_byte(struct kunit *test) static void test_clobber_redzone_free(struct kunit *test) { struct kmem_cache *s = kmem_cache_create("TestSlub_RZ_free", 64, 0, - SLAB_RED_ZONE, NULL); + SLAB_RED_ZONE|SLAB_NO_USER_FLAGS, NULL); u8 *p = kmem_cache_alloc(s, GFP_KERNEL); kasan_disable_current(); diff --git a/mm/slab.h b/mm/slab.h index fd7ae2024897..f7d018100994 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -331,7 +331,7 @@ static inline slab_flags_t kmem_cache_flags(unsigned int object_size, SLAB_ACCOUNT) #elif defined(CONFIG_SLUB) #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ - SLAB_TEMPORARY | SLAB_ACCOUNT) + SLAB_TEMPORARY | SLAB_ACCOUNT | SLAB_NO_USER_FLAGS) #else #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE) #endif @@ -350,7 +350,8 @@ static inline slab_flags_t kmem_cache_flags(unsigned int object_size, SLAB_NOLEAKTRACE | \ SLAB_RECLAIM_ACCOUNT | \ SLAB_TEMPORARY | \ - SLAB_ACCOUNT) + SLAB_ACCOUNT | \ + SLAB_NO_USER_FLAGS) bool __kmem_cache_empty(struct kmem_cache *); int __kmem_cache_shutdown(struct kmem_cache *); diff --git a/mm/slub.c b/mm/slub.c index 74d92aa4a3a2..4c78f5919356 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1584,6 +1584,9 @@ slab_flags_t kmem_cache_flags(unsigned int object_size, slab_flags_t block_flags; slab_flags_t slub_debug_local = slub_debug; + if (flags & SLAB_NO_USER_FLAGS) + return flags; + /* * If the slab cache is for debugging (e.g. kmemleak) then * don't store user (stack trace) information by default,