X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=mm%2Fslub.c;h=7277413ebc8b9a75806fba91103f57557b248cc3;hb=870d4b12ad15d21c5db67b373bdc2f62cfe2ec64;hp=9cde663bbb1096fe544fb710ed3287dc33666e68;hpb=becfda68abca673d61d5cc953e8e099816db99d9;p=karo-tx-linux.git diff --git a/mm/slub.c b/mm/slub.c index 9cde663bbb10..7277413ebc8b 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -124,6 +124,14 @@ static inline int kmem_cache_debug(struct kmem_cache *s) #endif } +static inline void *fixup_red_left(struct kmem_cache *s, void *p) +{ + if (kmem_cache_debug(s) && s->flags & SLAB_RED_ZONE) + p += s->red_left_pad; + + return p; +} + static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s) { #ifdef CONFIG_SLUB_CPU_PARTIAL @@ -163,6 +171,14 @@ static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s) #define DEBUG_DEFAULT_FLAGS (SLAB_CONSISTENCY_CHECKS | SLAB_RED_ZONE | \ SLAB_POISON | SLAB_STORE_USER) +/* + * These debug flags cannot use CMPXCHG because there might be consistency + * issues when checking or reading debug information + */ +#define SLAB_NO_CMPXCHG (SLAB_CONSISTENCY_CHECKS | SLAB_STORE_USER | \ + SLAB_TRACE) + + /* * Debugging flags that require metadata to be stored in the slab. These get * disabled when slub_debug=O is used and a cache's min order increases with @@ -224,24 +240,6 @@ static inline void stat(const struct kmem_cache *s, enum stat_item si) * Core slab cache functions *******************************************************************/ -/* Verify that a pointer has an address that is valid within a slab page */ -static inline int check_valid_pointer(struct kmem_cache *s, - struct page *page, const void *object) -{ - void *base; - - if (!object) - return 1; - - base = page_address(page); - if (object < base || object >= base + page->objects * s->size || - (object - base) % s->size) { - return 0; - } - - return 1; -} - static inline void *get_freepointer(struct kmem_cache *s, void *object) { return *(void **)(object + s->offset); @@ -256,11 +254,10 @@ static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) { void *p; -#ifdef CONFIG_DEBUG_PAGEALLOC + if (!debug_pagealloc_enabled()) + return get_freepointer(s, object); + probe_kernel_read(&p, (void **)(object + s->offset), sizeof(p)); -#else - p = get_freepointer(s, object); -#endif return p; } @@ -271,12 +268,14 @@ static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) /* Loop over all objects in a slab */ #define for_each_object(__p, __s, __addr, __objects) \ - for (__p = (__addr); __p < (__addr) + (__objects) * (__s)->size;\ - __p += (__s)->size) + for (__p = fixup_red_left(__s, __addr); \ + __p < (__addr) + (__objects) * (__s)->size; \ + __p += (__s)->size) #define for_each_object_idx(__p, __idx, __s, __addr, __objects) \ - for (__p = (__addr), __idx = 1; __idx <= __objects;\ - __p += (__s)->size, __idx++) + for (__p = fixup_red_left(__s, __addr), __idx = 1; \ + __idx <= __objects; \ + __p += (__s)->size, __idx++) /* Determine object index from a given position */ static inline int slab_index(void *p, struct kmem_cache *s, void *addr) @@ -434,6 +433,22 @@ static void get_map(struct kmem_cache *s, struct page *page, unsigned long *map) set_bit(slab_index(p, s, addr), map); } +static inline int size_from_object(struct kmem_cache *s) +{ + if (s->flags & SLAB_RED_ZONE) + return s->size - s->red_left_pad; + + return s->size; +} + +static inline void *restore_red_left(struct kmem_cache *s, void *p) +{ + if (s->flags & SLAB_RED_ZONE) + p -= s->red_left_pad; + + return p; +} + /* * Debug settings: */ @@ -467,6 +482,26 @@ static inline void metadata_access_disable(void) /* * Object debugging */ + +/* Verify that a pointer has an address that is valid within a slab page */ +static inline int check_valid_pointer(struct kmem_cache *s, + struct page *page, void *object) +{ + void *base; + + if (!object) + return 1; + + base = page_address(page); + object = restore_red_left(s, object); + if (object < base || object >= base + page->objects * s->size || + (object - base) % s->size) { + return 0; + } + + return 1; +} + static void print_section(char *text, u8 *addr, unsigned int length) { metadata_access_enable(); @@ -606,7 +641,9 @@ static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p) pr_err("INFO: Object 0x%p @offset=%tu fp=0x%p\n\n", p, p - addr, get_freepointer(s, p)); - if (p > addr + 16) + if (s->flags & SLAB_RED_ZONE) + print_section("Redzone ", p - s->red_left_pad, s->red_left_pad); + else if (p > addr + 16) print_section("Bytes b4 ", p - 16, 16); print_section("Object ", p, min_t(unsigned long, s->object_size, @@ -623,9 +660,9 @@ static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p) if (s->flags & SLAB_STORE_USER) off += 2 * sizeof(struct track); - if (off != s->size) + if (off != size_from_object(s)) /* Beginning of the filler is the free pointer */ - print_section("Padding ", p + off, s->size - off); + print_section("Padding ", p + off, size_from_object(s) - off); dump_stack(); } @@ -655,6 +692,9 @@ static void init_object(struct kmem_cache *s, void *object, u8 val) { u8 *p = object; + if (s->flags & SLAB_RED_ZONE) + memset(p - s->red_left_pad, val, s->red_left_pad); + if (s->flags & __OBJECT_POISON) { memset(p, POISON_FREE, s->object_size - 1); p[s->object_size - 1] = POISON_END; @@ -747,11 +787,11 @@ static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p) /* We also have user information there */ off += 2 * sizeof(struct track); - if (s->size == off) + if (size_from_object(s) == off) return 1; return check_bytes_and_report(s, page, p, "Object padding", - p + off, POISON_INUSE, s->size - off); + p + off, POISON_INUSE, size_from_object(s) - off); } /* Check the pad bytes at the end of a slab page */ @@ -795,6 +835,10 @@ static int check_object(struct kmem_cache *s, struct page *page, u8 *endobject = object + s->object_size; if (s->flags & SLAB_RED_ZONE) { + if (!check_bytes_and_report(s, page, object, "Redzone", + object - s->red_left_pad, val, s->red_left_pad)) + return 0; + if (!check_bytes_and_report(s, page, object, "Redzone", endobject, val, s->inuse - s->object_size)) return 0; @@ -906,14 +950,14 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search) max_objects = MAX_OBJS_PER_PAGE; if (page->objects != max_objects) { - slab_err(s, page, "Wrong number of objects. Found %d but " - "should be %d", page->objects, max_objects); + slab_err(s, page, "Wrong number of objects. Found %d but should be %d", + page->objects, max_objects); page->objects = max_objects; slab_fix(s, "Number of objects adjusted."); } if (page->inuse != page->objects - nr) { - slab_err(s, page, "Wrong object count. Counter is %d but " - "counted were %d", page->inuse, page->objects - nr); + slab_err(s, page, "Wrong object count. Counter is %d but counted were %d", + page->inuse, page->objects - nr); page->inuse = page->objects - nr; slab_fix(s, "Object count adjusted."); } @@ -1073,8 +1117,8 @@ static inline int free_consistency_checks(struct kmem_cache *s, if (unlikely(s != page->slab_cache)) { if (!PageSlab(page)) { - slab_err(s, page, "Attempt to free object(0x%p) " - "outside of slab", object); + slab_err(s, page, "Attempt to free object(0x%p) outside of slab", + object); } else if (!page->slab_cache) { pr_err("SLUB : no slab for object 0x%p.\n", object); @@ -1382,7 +1426,7 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) */ alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL; if ((alloc_gfp & __GFP_DIRECT_RECLAIM) && oo_order(oo) > oo_order(s->min)) - alloc_gfp = (alloc_gfp | __GFP_NOMEMALLOC) & ~__GFP_DIRECT_RECLAIM; + alloc_gfp = (alloc_gfp | __GFP_NOMEMALLOC) & ~(__GFP_RECLAIM|__GFP_NOFAIL); page = alloc_slab_page(s, alloc_gfp, node, oo); if (unlikely(!page)) { @@ -1437,7 +1481,7 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) set_freepointer(s, p, NULL); } - page->freelist = start; + page->freelist = fixup_red_left(s, start); page->inuse = page->objects; page->frozen = 1; @@ -1495,7 +1539,8 @@ static void __free_slab(struct kmem_cache *s, struct page *page) page_mapcount_reset(page); if (current->reclaim_state) current->reclaim_state->reclaimed_slab += pages; - __free_kmem_pages(page, order); + memcg_uncharge_slab(page, order, s); + __free_pages(page, order); } #define need_reserve_slab_rcu \ @@ -2191,8 +2236,8 @@ slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs)) return; - pr_warn("SLUB: Unable to allocate memory on node %d (gfp=0x%x)\n", - nid, gfpflags); + pr_warn("SLUB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", + nid, gfpflags, &gfpflags); pr_warn(" cache: %s, object size: %d, buffer size: %d, default order: %d, min order: %d\n", s->name, s->object_size, s->size, oo_order(s->oo), oo_order(s->min)); @@ -3266,7 +3311,7 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order) */ size += 2 * sizeof(struct track); - if (flags & SLAB_RED_ZONE) + if (flags & SLAB_RED_ZONE) { /* * Add some empty padding so that we can catch * overwrites from earlier objects rather than let @@ -3275,6 +3320,11 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order) * of the object. */ size += sizeof(void *); + + s->red_left_pad = sizeof(void *); + s->red_left_pad = ALIGN(s->red_left_pad, s->align); + size += s->red_left_pad; + } #endif /* @@ -3338,7 +3388,7 @@ static int kmem_cache_open(struct kmem_cache *s, unsigned long flags) #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) - if (system_has_cmpxchg_double() && (s->flags & SLAB_DEBUG_FLAGS) == 0) + if (system_has_cmpxchg_double() && (s->flags & SLAB_NO_CMPXCHG) == 0) /* Enable fast mode */ s->flags |= __CMPXCHG_DOUBLE; #endif @@ -3389,10 +3439,9 @@ static int kmem_cache_open(struct kmem_cache *s, unsigned long flags) free_kmem_cache_nodes(s); error: if (flags & SLAB_PANIC) - panic("Cannot create slab %s size=%lu realsize=%u " - "order=%u offset=%u flags=%lx\n", - s->name, (unsigned long)s->size, s->size, - oo_order(s->oo), s->offset, flags); + panic("Cannot create slab %s size=%lu realsize=%u order=%u offset=%u flags=%lx\n", + s->name, (unsigned long)s->size, s->size, + oo_order(s->oo), s->offset, flags); return -EINVAL; } @@ -4846,7 +4895,6 @@ static ssize_t red_zone_store(struct kmem_cache *s, s->flags &= ~SLAB_RED_ZONE; if (buf[0] == '1') { - s->flags &= ~__CMPXCHG_DOUBLE; s->flags |= SLAB_RED_ZONE; } calculate_sizes(s, -1); @@ -4867,7 +4915,6 @@ static ssize_t poison_store(struct kmem_cache *s, s->flags &= ~SLAB_POISON; if (buf[0] == '1') { - s->flags &= ~__CMPXCHG_DOUBLE; s->flags |= SLAB_POISON; } calculate_sizes(s, -1);