diff --git a/include/asm-ia64/page.h b/include/asm-ia64/page.h
index 9dd9da1..5e6362a 100644
--- a/include/asm-ia64/page.h
+++ b/include/asm-ia64/page.h
@@ -110,8 +110,9 @@
 # define pfn_to_page(pfn)	(mem_map + (pfn))
 #elif defined(CONFIG_DISCONTIGMEM)
 extern struct page *vmem_map;
+extern unsigned long min_low_pfn;
 extern unsigned long max_low_pfn;
-# define pfn_valid(pfn)		(((pfn) < max_low_pfn) && ia64_pfn_valid(pfn))
+# define pfn_valid(pfn)		(((pfn) >= min_low_pfn) && ((pfn) < max_low_pfn) && ia64_pfn_valid(pfn))
 # define page_to_pfn(page)	((unsigned long) (page - vmem_map))
 # define pfn_to_page(pfn)	(vmem_map + (pfn))
 #endif