diff --git a/lib/libc/i386/sys/i386_get_ldt.2 b/lib/libc/i386/sys/i386_get_ldt.2
index 8db81b3d8fe5..5aec1bf56a19 100644
--- a/lib/libc/i386/sys/i386_get_ldt.2
+++ b/lib/libc/i386/sys/i386_get_ldt.2
@@ -69,6 +69,10 @@ can be either segment_descriptor or gate_descriptor and are defined in
 .Fd <i386/segments.h> .
 These structures are defined by the architecture
 as disjoint bit-fields, so care must be taken in constructing them.
+.Pp
+Note that you must have
+.Dq options USER_LDT
+in your kernel configuration file to use these functions.
 .Sh RETURN VALUES
 Upon successful completion,
 .Fn i386_get_ldt