Index: kernel/arch/amd64/src/mm/km.c
===================================================================
--- kernel/arch/amd64/src/mm/km.c	(revision 40c8c17482d672e755c855c6fd5664b0e933e483)
+++ kernel/arch/amd64/src/mm/km.c	(revision faba83975da4ba5bb605f70d4e02e065f9513e84)
@@ -34,4 +34,6 @@
 #include <mm/km.h>
 #include <config.h>
+#include <typedefs.h>
+#include <macros.h>
 
 void km_identity_arch_init(void)
@@ -47,4 +49,10 @@
 }
 
+bool km_is_non_identity_arch(uintptr_t addr)
+{
+	return iswithin(KM_AMD64_NON_IDENTITY_START,
+	    KM_AMD64_NON_IDENTITY_SIZE, addr, 1);
+}
+
 /** @}
  */