diff -Nur linux-4.14.6_orig/lib/ioremap.c linux-4.14.6/lib/ioremap.c
--- linux-4.14.6_orig/lib/ioremap.c	2017-12-14 09:53:15.000000000 +0100
+++ linux-4.14.6/lib/ioremap.c	2017-12-14 17:20:45.906872824 +0100
@@ -179,3 +179,5 @@
 
 	return err;
 }
+
+EXPORT_SYMBOL_GPL(ioremap_page_range);