Merge branches 'slab/documentation', 'slab/fixes', 'slob/cleanups' and 'slub/fixes' into for-linus

mm/util.c

@@ -168,6 +168,10 @@ EXPORT_SYMBOL(krealloc);
  *
  * The memory of the object @p points to is zeroed before freed.
  * If @p is %NULL, kzfree() does nothing.
+ *
+ * Note: this function zeroes the whole allocated buffer which can be a good
+ * deal bigger than the requested buffer size passed to kmalloc(). So be
+ * careful when using this function in performance sensitive code.
  */
 void kzfree(const void *p)
 {