diff --git a/mm/page_ext.c b/mm/page_ext.c
index a3616f7a0e9e..de36d5f6ca71 100644
--- a/mm/page_ext.c
+++ b/mm/page_ext.c
@@ -131,6 +131,7 @@ struct page_ext *lookup_page_ext(const struct page *page)
 					MAX_ORDER_NR_PAGES);
 	return get_entry(base, index);
 }
+EXPORT_SYMBOL_GPL(lookup_page_ext);
 
 static int __init alloc_node_page_ext(int nid)
 {
@@ -201,6 +202,7 @@ struct page_ext *lookup_page_ext(const struct page *page)
 		return NULL;
 	return get_entry(section->page_ext, pfn);
 }
+EXPORT_SYMBOL_GPL(lookup_page_ext);
 
 static void *__meminit alloc_page_ext(size_t size, int nid)
 {