1 files changed, 23 insertions, 19 deletions

diff --git a/mm/slab.c b/mm/slab.c
index 5920a412b377..1115e2065bfc 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -148,10 +148,11 @@
  * Usually, the kmalloc caches are cache_line_size() aligned, except when
  * DEBUG and FORCED_DEBUG are enabled, then they are BYTES_PER_WORD aligned.
  * Some archs want to perform DMA into kmalloc caches and need a guaranteed
- * alignment larger than BYTES_PER_WORD. ARCH_KMALLOC_MINALIGN allows that.
- * Note that this flag disables some debug features.
+ * alignment larger than the alignment of a 64-bit integer.
+ * ARCH_KMALLOC_MINALIGN allows that.
+ * Note that increasing this value may disable some debug features.
  */
-#define ARCH_KMALLOC_MINALIGN 0
+#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
 #endif
 
 #ifndef ARCH_SLAB_MINALIGN
@@ -536,19 +537,22 @@ static int obj_size(struct kmem_cache *cachep)
         return cachep->obj_size;
 }
 
-static unsigned long *dbg_redzone1(struct kmem_cache *cachep, void *objp)
+static unsigned long long *dbg_redzone1(struct kmem_cache *cachep, void *objp)
 {
         BUG_ON(!(cachep->flags & SLAB_RED_ZONE));
-        return (unsigned long*) (objp+obj_offset(cachep)-BYTES_PER_WORD);
+        return (unsigned long long*) (objp + obj_offset(cachep) -
+                                      sizeof(unsigned long long));
 }
 
-static unsigned long *dbg_redzone2(struct kmem_cache *cachep, void *objp)
+static unsigned long long *dbg_redzone2(struct kmem_cache *cachep, void *objp)
 {
         BUG_ON(!(cachep->flags & SLAB_RED_ZONE));
         if (cachep->flags & SLAB_STORE_USER)
-                return (unsigned long *)(objp + cachep->buffer_size -
-                                         2 * BYTES_PER_WORD);
-        return (unsigned long *)(objp + cachep->buffer_size - BYTES_PER_WORD);
+                return (unsigned long long *)(objp + cachep->buffer_size -
+                                              sizeof(unsigned long long) -
+                                              BYTES_PER_WORD);
+        return (unsigned long long *) (objp + cachep->buffer_size -
+                                       sizeof(unsigned long long));
 }
 
 static void **dbg_userword(struct kmem_cache *cachep, void *objp)
@@ -561,8 +565,8 @@ static void **dbg_userword(struct kmem_cache *cachep, void *objp)
 
 #define obj_offset(x)                   0
 #define obj_size(cachep)                (cachep->buffer_size)
-#define dbg_redzone1(cachep, objp)      ({BUG(); (unsigned long *)NULL;})
-#define dbg_redzone2(cachep, objp)      ({BUG(); (unsigned long *)NULL;})
+#define dbg_redzone1(cachep, objp)      ({BUG(); (unsigned long long *)NULL;})
+#define dbg_redzone2(cachep, objp)      ({BUG(); (unsigned long long *)NULL;})
 #define dbg_userword(cachep, objp)      ({BUG(); (void **)NULL;})
 
 #endif
@@ -1776,7 +1780,7 @@ static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines)
         char *realobj;
 
         if (cachep->flags & SLAB_RED_ZONE) {
-                printk(KERN_ERR "Redzone: 0x%lx/0x%lx.\n",
+                printk(KERN_ERR "Redzone: 0x%llx/0x%llx.\n",
                         *dbg_redzone1(cachep, objp),
                         *dbg_redzone2(cachep, objp));
         }
@@ -2239,7 +2243,7 @@ kmem_cache_create (const char *name, size_t size, size_t align,
          * is greater than BYTES_PER_WORD.
          */
         if (flags & SLAB_RED_ZONE || flags & SLAB_STORE_USER)
-                ralign = BYTES_PER_WORD;
+                ralign = __alignof__(unsigned long long);
 
         /* 2) arch mandated alignment */
         if (ralign < ARCH_SLAB_MINALIGN) {
@@ -2250,7 +2254,7 @@ kmem_cache_create (const char *name, size_t size, size_t align,
                 ralign = align;
         }
         /* disable debug if necessary */
-        if (ralign > BYTES_PER_WORD)
+        if (ralign > __alignof__(unsigned long long))
                 flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
         /*
          * 4) Store it.
@@ -2271,8 +2275,8 @@ kmem_cache_create (const char *name, size_t size, size_t align,
          */
         if (flags & SLAB_RED_ZONE) {
                 /* add space for red zone words */
-                cachep->obj_offset += BYTES_PER_WORD;
-                size += 2 * BYTES_PER_WORD;
+                cachep->obj_offset += sizeof(unsigned long long);
+                size += 2 * sizeof(unsigned long long);
         }
         if (flags & SLAB_STORE_USER) {
                 /* user store requires one word storage behind the end of
@@ -2833,7 +2837,7 @@ static void kfree_debugcheck(const void *objp)
 
 static inline void verify_redzone_free(struct kmem_cache *cache, void *obj)
 {
-        unsigned long redzone1, redzone2;
+        unsigned long long redzone1, redzone2;
 
         redzone1 = *dbg_redzone1(cache, obj);
         redzone2 = *dbg_redzone2(cache, obj);
@@ -2849,7 +2853,7 @@ static inline void verify_redzone_free(struct kmem_cache *cache, void *obj)
         else
                 slab_error(cache, "memory outside object was overwritten");
 
-        printk(KERN_ERR "%p: redzone 1:0x%lx, redzone 2:0x%lx.\n",
+        printk(KERN_ERR "%p: redzone 1:0x%llx, redzone 2:0x%llx.\n",
                         obj, redzone1, redzone2);
 }
 
@@ -3065,7 +3069,7 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,
                         slab_error(cachep, "double free, or memory outside"
                                                 " object was overwritten");
                         printk(KERN_ERR
-                                "%p: redzone 1:0x%lx, redzone 2:0x%lx\n",
+                                "%p: redzone 1:0x%llx, redzone 2:0x%llx\n",
                                 objp, *dbg_redzone1(cachep, objp),
                                 *dbg_redzone2(cachep, objp));
                 }