Commit a285909f authored by Hyeonggon Yoo's avatar Hyeonggon Yoo Committed by Vlastimil Babka
Browse files

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: default avatarVlastimil Babka <vbabka@suse.cz>
Signed-off-by: default avatarHyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: default avatarVlastimil Babka <vbabka@suse.cz>
Link: https://lore.kernel.org/r/Yk0sY9yoJhFEXWOg@hyeyoo
parent 1e703d05

include/linux/slab.h

+7 −0
Original line number Diff line number Diff line
@@ -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)

lib/slub_kunit.c

+5 −5
Original line number Diff line number Diff line
@@ -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();

mm/slab.h

+3 −2
Original line number Diff line number Diff line
@@ -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 *);

mm/slub.c

+3 −0
Original line number Diff line number Diff line
@@ -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,