diff --git a/arch/x86/kernel/memory.c b/arch/x86/kernel/memory.c
index f2e8adc9..fe6077fe 100644
--- a/arch/x86/kernel/memory.c
+++ b/arch/x86/kernel/memory.c
@@ -10,7 +10,7 @@
 static char *last_page;
 extern char _head[], _end[];
 
-struct ihk_mc_pa_ops *pa_ops;
+static struct ihk_mc_pa_ops *pa_ops;
 
 extern unsigned long x86_kernel_phys_base;