alloc_empty_sheaf() allocates sheafs from SLAB_KMALLOC caches using __GFP_NO_OBJ_EXT to avoid recursion, however it does not mark their allocation tags empty before freeing, which results in a warning when CONFIG_MEM_ALLOC_PROFILING_DEBUG is set. Fix this by marking allocation tags for such allocations as empty. Reported-by: David Wang <00107082@163.com> Closes: https://lore.kernel.org/all/20260223155128.3849-1-00107082@163.com/ Analyzed-by: Harry Yoo Signed-off-by: Suren Baghdasaryan --- mm/slab.h | 4 ++-- mm/slub.c | 17 ++++++++++------- 2 files changed, 12 insertions(+), 9 deletions(-) diff --git a/mm/slab.h b/mm/slab.h index 71c7261bf822..f6ef862b60ef 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -290,14 +290,14 @@ static inline void *nearest_obj(struct kmem_cache *cache, /* Determine object index from a given position */ static inline unsigned int __obj_to_index(const struct kmem_cache *cache, - void *addr, void *obj) + void *addr, const void *obj) { return reciprocal_divide(kasan_reset_tag(obj) - addr, cache->reciprocal_size); } static inline unsigned int obj_to_index(const struct kmem_cache *cache, - const struct slab *slab, void *obj) + const struct slab *slab, const void *obj) { if (is_kfence_address(obj)) return 0; diff --git a/mm/slub.c b/mm/slub.c index 862642c165ed..3ddbe654cd56 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2041,18 +2041,18 @@ static inline void dec_slabs_node(struct kmem_cache *s, int node, #ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG -static inline void mark_objexts_empty(struct slabobj_ext *obj_exts) +static inline void mark_objexts_empty(const void *obj) { - struct slab *obj_exts_slab; + struct slab *obj_slab; unsigned long slab_exts; - obj_exts_slab = virt_to_slab(obj_exts); - slab_exts = slab_obj_exts(obj_exts_slab); + obj_slab = virt_to_slab(obj); + slab_exts = slab_obj_exts(obj_slab); if (slab_exts) { get_slab_obj_exts(slab_exts); - unsigned int offs = obj_to_index(obj_exts_slab->slab_cache, - obj_exts_slab, obj_exts); - struct slabobj_ext *ext = slab_obj_ext(obj_exts_slab, + unsigned int offs = obj_to_index(obj_slab->slab_cache, + obj_slab, obj); + struct slabobj_ext *ext = slab_obj_ext(obj_slab, slab_exts, offs); if (unlikely(is_codetag_empty(&ext->ref))) { @@ -2783,6 +2783,9 @@ static inline struct slab_sheaf *alloc_empty_sheaf(struct kmem_cache *s, static void free_empty_sheaf(struct kmem_cache *s, struct slab_sheaf *sheaf) { + if (s->flags & SLAB_KMALLOC) + mark_objexts_empty(sheaf); + kfree(sheaf); stat(s, SHEAF_FREE); base-commit: 7dff99b354601dd01829e1511711846e04340a69 -- 2.53.0.371.g1d285c8824-goog