1 files changed, 4 insertions, 2 deletions

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index a8140a9a65e8..9a5d5590bd39 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -748,7 +748,7 @@ extern struct zone *next_zone(struct zone *zone);
 #define PAGE_SECTION_MASK       (~(PAGES_PER_SECTION-1))
 
 #define SECTION_BLOCKFLAGS_BITS \
-                ((SECTION_SIZE_BITS - (MAX_ORDER-1)) * NR_PAGEBLOCK_BITS)
+                ((1 << (PFN_SECTION_SHIFT - (MAX_ORDER-1))) * NR_PAGEBLOCK_BITS)
 
 #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
 #error Allocator MAX_ORDER exceeds SECTION_SIZE
@@ -769,7 +769,9 @@ struct mem_section {
          * before using it wrong.
          */
         unsigned long section_mem_map;
-        DECLARE_BITMAP(pageblock_flags, SECTION_BLOCKFLAGS_BITS);
+
+        /* See declaration of similar field in struct zone */
+        unsigned long *pageblock_flags;
 };
 
 #ifdef CONFIG_SPARSEMEM_EXTREME