1 files changed, 5 insertions, 1 deletions

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index c9c4a81b9767..a507f43ad221 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1151,13 +1151,17 @@ struct mem_section {
 #define SECTION_ROOT_MASK       (SECTIONS_PER_ROOT - 1)
 
 #ifdef CONFIG_SPARSEMEM_EXTREME
-extern struct mem_section *mem_section[NR_SECTION_ROOTS];
+extern struct mem_section **mem_section;
 #else
 extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
 #endif
 
 static inline struct mem_section *__nr_to_section(unsigned long nr)
 {
+#ifdef CONFIG_SPARSEMEM_EXTREME
+        if (!mem_section)
+                return NULL;
+#endif
         if (!mem_section[SECTION_NR_TO_ROOT(nr)])
                 return NULL;
         return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];