Found this during debugging an other problem.  The issue was that
after ``sudo -i'' and a ``cd /usr/lib/systemd/system/'' followed
later by a shutdown may fail with (journalctl -b -1):

 systemd-exit.service: Failed at step CHDIR spawning: /usr/bin/kill

which then caused the subsequent fault that umounting the users
home directories done by automount are busy.

--- systemd-210/units/user/systemd-exit.service.in
+++ systemd-210/units/user/systemd-exit.service.in	2014-03-25 16:59:20.406235916 +0000
@@ -10,8 +10,9 @@ Description=Exit the Session
 Documentation=man:systemd.special(7)
 DefaultDependencies=no
 Requires=shutdown.target
-After=shutdown.target
+After=shutdown.target multi-user.target
 
 [Service]
 Type=oneshot
-ExecStart=@KILL@ -s 58 $MANAGERPID
+WorkingDirectory=/
+ExecStart=@KILL@ -s SIGRTMIN+24 $MANAGERPID