diff --git a/Documentation/i386/boot.txt b/Documentation/i386/boot.txt
index 10312be..c51314b 100644
--- a/Documentation/i386/boot.txt
+++ b/Documentation/i386/boot.txt
@@ -181,6 +181,7 @@
 	5  ELILO
 	7  GRuB
 	8  U-BOOT
+	9  Xen
 
 	Please contact <hpa@zytor.com> if you need a bootloader ID
 	value assigned.
diff --git a/Documentation/i386/zero-page.txt b/Documentation/i386/zero-page.txt
index df28c74..c04a421 100644
--- a/Documentation/i386/zero-page.txt
+++ b/Documentation/i386/zero-page.txt
@@ -63,6 +63,10 @@
 				2 for bootsect-loader
 				3 for SYSLINUX
 				4 for ETHERBOOT
+				5 for ELILO
+				7 for GRuB
+				8 for U-BOOT
+				9 for Xen
 				V = version
 0x211	char		loadflags:
 			bit0 = 1: kernel is loaded high (bzImage)