diff --git a/src/logind.h b/src/logind.h
index be8bb1d389..5c513b4021 100644
--- a/src/logind.h
+++ b/src/logind.h
@@ -39,6 +39,7 @@
  * direct client API
  * D-Bus method: AttachDevices(seat, devices[]);
  * D-Bus method: SetLinger(user, bool b);
+ * kill cgroup immediately when fd is EOF.
  *
  * non-local X11 server
  * reboot/shutdown halt management