Index: head/share/man/man9/contigmalloc.9
===================================================================
--- head/share/man/man9/contigmalloc.9
+++ head/share/man/man9/contigmalloc.9
@@ -25,7 +25,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 19, 2007
+.Dd January 29, 2015
 .Dt CONTIGMALLOC 9
 .Os
 .Sh NAME
@@ -100,6 +100,13 @@
 .Dv M_NOWAIT
 is specified, it may select a page for reclamation that must first be
 written to backing storage, causing it to sleep.
+.Pp
+The
+.Fn contigfree
+function does not accept
+.Dv NULL
+as an address input, unlike
+.Xr free 9 .
 .Sh RETURN VALUES
 The
 .Fn contigmalloc