diff --git a/arch/x86/kernel/memory.c b/arch/x86/kernel/memory.c
index a1bf7eb1..03239e6b 100644
--- a/arch/x86/kernel/memory.c
+++ b/arch/x86/kernel/memory.c
@@ -683,7 +683,7 @@ void ihk_mc_reserve_arch_pages(unsigned long start, unsigned long end,
 
 void ihk_mc_set_page_allocator(struct ihk_mc_pa_ops *ops)
 {
-	last_page = NULL;
+	last_page = (void *)-1;
 	pa_ops = ops;
 }