diff --git a/xen/common/page_alloc.c b/xen/common/page_alloc.c
index 629fbc97a5..28963d1419 100644
--- a/xen/common/page_alloc.c
+++ b/xen/common/page_alloc.c
@@ -89,7 +89,11 @@ PAGE_LIST_HEAD(page_broken_list);
  * BOOT-TIME ALLOCATOR
  */
 
-static unsigned long __initdata first_valid_mfn = ~0UL;
+/*
+ * first_valid_mfn is exported because it is use in ARM specific NUMA
+ * helpers. See comment in asm-arm/numa.h.
+ */
+unsigned long first_valid_mfn = ~0UL;
 
 static struct bootmem_region {
     unsigned long s, e; /* MFNs @s through @e-1 inclusive are free */
diff --git a/xen/include/asm-arm/numa.h b/xen/include/asm-arm/numa.h
index a2c1a3476d..7e0b69413d 100644
--- a/xen/include/asm-arm/numa.h
+++ b/xen/include/asm-arm/numa.h
@@ -12,9 +12,15 @@ static inline __attribute__((pure)) nodeid_t phys_to_nid(paddr_t addr)
     return 0;
 }
 
+/*
+ * TODO: make first_valid_mfn static when NUMA is supported on Arm, this
+ * is required because the dummy helpers are using it.
+ */
+extern unsigned long first_valid_mfn;
+
 /* XXX: implement NUMA support */
-#define node_spanned_pages(nid) (total_pages)
-#define node_start_pfn(nid) (pdx_to_pfn(frametable_base_pdx))
+#define node_spanned_pages(nid) (max_page - first_valid_mfn)
+#define node_start_pfn(nid) (first_valid_mfn)
 #define __node_distance(a, b) (20)
 
 static inline unsigned int arch_get_dma_bitsize(void)