diff options
| -rw-r--r-- | mm/slab.c | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/mm/slab.c b/mm/slab.c index 00584dbbec0..d47d0e18697 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2096,6 +2096,15 @@ kmem_cache_create (const char *name, size_t size, size_t align, } else { ralign = BYTES_PER_WORD; } + + /* + * Redzoning and user store require word alignment. Note this will be + * overridden by architecture or caller mandated alignment if either + * is greater than BYTES_PER_WORD. + */ + if (flags & SLAB_RED_ZONE || flags & SLAB_STORE_USER) + ralign = BYTES_PER_WORD; + /* 2) arch mandated alignment: disables debug if necessary */ if (ralign < ARCH_SLAB_MINALIGN) { ralign = ARCH_SLAB_MINALIGN; @@ -2109,8 +2118,7 @@ kmem_cache_create (const char *name, size_t size, size_t align, flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); } /* - * 4) Store it. Note that the debug code below can reduce - * the alignment to BYTES_PER_WORD. + * 4) Store it. */ align = ralign; @@ -2122,20 +2130,19 @@ kmem_cache_create (const char *name, size_t size, size_t align, #if DEBUG cachep->obj_size = size; + /* + * Both debugging options require word-alignment which is calculated + * into align above. + */ if (flags & SLAB_RED_ZONE) { - /* redzoning only works with word aligned caches */ - align = BYTES_PER_WORD; - /* add space for red zone words */ cachep->obj_offset += BYTES_PER_WORD; size += 2 * BYTES_PER_WORD; } if (flags & SLAB_STORE_USER) { - /* user store requires word alignment and - * one word storage behind the end of the real - * object. + /* user store requires one word storage behind the end of + * the real object. */ - align = BYTES_PER_WORD; size += BYTES_PER_WORD; } #if FORCED_DEBUG && defined(CONFIG_DEBUG_PAGEALLOC) |