diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt
index 9efceff51bfb..c25a53e69f1b 100644
--- a/Documentation/x86/boot.txt
+++ b/Documentation/x86/boot.txt
@@ -381,6 +381,7 @@ Protocol:	2.00+
 	A  Gujin
 	B  Qemu
 	C  Arcturus Networks uCbootloader
+	D  kexec-tools
 	E  Extended		(see ext_loader_type)
 	F  Special		(0xFF = undefined)
        10  Reserved