diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2ad2ad168efe930bb75391848e71f4ac8c61099b..4ba5e37127fca863af15fe3090f068ac295c0386 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5978,8 +5978,15 @@ int alloc_contig_range(unsigned long start, unsigned long end,
 
 void free_contig_range(unsigned long pfn, unsigned nr_pages)
 {
-	for (; nr_pages--; ++pfn)
-		__free_page(pfn_to_page(pfn));
+	unsigned int count = 0;
+
+	for (; nr_pages--; pfn++) {
+		struct page *page = pfn_to_page(pfn);
+
+		count += page_count(page) != 1;
+		__free_page(page);
+	}
+	WARN(count != 0, "%d pages are still in use!\n", count);
 }
 #endif