diff --git a/arch/x86/um/syscalls_64.c b/arch/x86/um/syscalls_64.c
index adb08eb5c22a..e6552275320b 100644
--- a/arch/x86/um/syscalls_64.c
+++ b/arch/x86/um/syscalls_64.c
@@ -6,6 +6,7 @@
  */
 
 #include <linux/sched.h>
+#include <linux/uaccess.h>
 #include <asm/prctl.h> /* XXX This should get the constants from libc */
 #include <os.h>