v4.19.13 snapshot.
diff --git a/include/linux/kernel-page-flags.h b/include/linux/kernel-page-flags.h
new file mode 100644
index 0000000..abd20ef
--- /dev/null
+++ b/include/linux/kernel-page-flags.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef LINUX_KERNEL_PAGE_FLAGS_H
+#define LINUX_KERNEL_PAGE_FLAGS_H
+
+#include <uapi/linux/kernel-page-flags.h>
+
+
+/* kernel hacking assistances
+ * WARNING: subject to change, never rely on them!
+ */
+#define KPF_RESERVED 32
+#define KPF_MLOCKED 33
+#define KPF_MAPPEDTODISK 34
+#define KPF_PRIVATE 35
+#define KPF_PRIVATE_2 36
+#define KPF_OWNER_PRIVATE 37
+#define KPF_ARCH 38
+#define KPF_UNCACHED 39
+#define KPF_SOFTDIRTY 40
+
+#endif /* LINUX_KERNEL_PAGE_FLAGS_H */