SLUB is the only remaining allocator. We can therefore get rid of the logic for allocator-specific flags: * Merge SLAB_CACHE_FLAGS into SLAB_CORE_FLAGS. * Remove CACHE_CREATE_MASK and instead mask out SLAB_DEBUG_FLAGS if !CONFIG_SLUB_DEBUG. SLAB_DEBUG_FLAGS is now defined unconditionally (no impact on existing code, which ignores it if !CONFIG_SLUB_DEBUG). * Define SLAB_FLAGS_PERMITTED in terms of SLAB_CORE_FLAGS and SLAB_DEBUG_FLAGS (no functional change). While at it also remove misleading comments that suggest that multiple allocators are available. Signed-off-by: Kevin Brodsky <kevin.brodsky@xxxxxxx> --- v1..v2: * Keep the SLAB_FLAGS_PERMITTED check and remove CACHE_CREATE_MASK instead. SLAB_DEBUG_FLAGS is now defined unconditionally and explicitly masked out. v1: https://lore.kernel.org/all/20250117113226.3484784-1-kevin.brodsky@xxxxxxx/ Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: Pekka Enberg <penberg@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Cc: Roman Gushchin <roman.gushchin@xxxxxxxxx> Cc: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx> --- mm/slab.h | 32 +++++--------------------------- mm/slab_common.c | 11 ++--------- 2 files changed, 7 insertions(+), 36 deletions(-) diff --git a/mm/slab.h b/mm/slab.h index e9fd9bf0bfa6..1a081f50f947 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -457,39 +457,17 @@ static inline bool is_kmalloc_normal(struct kmem_cache *s) return !(s->flags & (SLAB_CACHE_DMA|SLAB_ACCOUNT|SLAB_RECLAIM_ACCOUNT)); } -/* Legal flag mask for kmem_cache_create(), for various configurations */ #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \ SLAB_CACHE_DMA32 | SLAB_PANIC | \ - SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS ) + SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS | \ + SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ + SLAB_TEMPORARY | SLAB_ACCOUNT | \ + SLAB_NO_USER_FLAGS | SLAB_KMALLOC | SLAB_NO_MERGE) -#ifdef CONFIG_SLUB_DEBUG #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ SLAB_TRACE | SLAB_CONSISTENCY_CHECKS) -#else -#define SLAB_DEBUG_FLAGS (0) -#endif -#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ - SLAB_TEMPORARY | SLAB_ACCOUNT | \ - SLAB_NO_USER_FLAGS | SLAB_KMALLOC | SLAB_NO_MERGE) - -/* Common flags available with current configuration */ -#define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS) - -/* Common flags permitted for kmem_cache_create */ -#define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \ - SLAB_RED_ZONE | \ - SLAB_POISON | \ - SLAB_STORE_USER | \ - SLAB_TRACE | \ - SLAB_CONSISTENCY_CHECKS | \ - SLAB_NOLEAKTRACE | \ - SLAB_RECLAIM_ACCOUNT | \ - SLAB_TEMPORARY | \ - SLAB_ACCOUNT | \ - SLAB_KMALLOC | \ - SLAB_NO_MERGE | \ - SLAB_NO_USER_FLAGS) +#define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS) bool __kmem_cache_empty(struct kmem_cache *); int __kmem_cache_shutdown(struct kmem_cache *); diff --git a/mm/slab_common.c b/mm/slab_common.c index 69f2d19010de..50b9c6497171 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -298,6 +298,8 @@ struct kmem_cache *__kmem_cache_create_args(const char *name, static_branch_enable(&slub_debug_enabled); if (flags & SLAB_STORE_USER) stack_depot_init(); +#else + flags &= ~SLAB_DEBUG_FLAGS; #endif mutex_lock(&slab_mutex); @@ -307,20 +309,11 @@ struct kmem_cache *__kmem_cache_create_args(const char *name, goto out_unlock; } - /* Refuse requests with allocator specific flags */ if (flags & ~SLAB_FLAGS_PERMITTED) { err = -EINVAL; goto out_unlock; } - /* - * Some allocators will constraint the set of valid flags to a subset - * of all flags. We expect them to define CACHE_CREATE_MASK in this - * case, and we'll just provide them with a sanitized version of the - * passed flags. - */ - flags &= CACHE_CREATE_MASK; - /* Fail closed on bad usersize of useroffset values. */ if (!IS_ENABLED(CONFIG_HARDENED_USERCOPY) || WARN_ON(!args->usersize && args->useroffset) || base-commit: ab18b8fff124c9b76ea12692571ca822dcd92854 -- 2.47.0