diff --git a/Documentation/sysrq.txt b/Documentation/sysrq.txt
index 10a0263..56b53e0 100644
--- a/Documentation/sysrq.txt
+++ b/Documentation/sysrq.txt
@@ -114,6 +114,8 @@
 
 'x'	- Used by xmon interface on ppc/powerpc platforms.
 
+'z'	- Dump the ftrace buffer
+
 '0'-'9' - Sets the console log level, controlling which kernel messages
           will be printed to your console. ('0', for example would make
           it so that only emergency messages like PANICs or OOPSes would