diff --git a/src/userprog/exception.h b/src/userprog/exception.h
new file mode 100644
index 0000000000000000000000000000000000000000..f83e615bb1e010c8723510a99abb01d714c0f275
--- /dev/null
+++ b/src/userprog/exception.h
@@ -0,0 +1,12 @@
+#ifndef USERPROG_EXCEPTION_H
+#define USERPROG_EXCEPTION_H
+
+/* Page fault error code bits that describe the cause of the exception.  */
+#define PF_P 0x1    /* 0: not-present page. 1: access rights violation. */
+#define PF_W 0x2    /* 0: read, 1: write. */
+#define PF_U 0x4    /* 0: kernel, 1: user process. */
+
+void exception_init (void);
+void exception_print_stats (void);
+
+#endif /* userprog/exception.h */