update-grub hangs when starting with systemd

[Zenaan Harkness <zen@freedbms.net>]

Anyone know why update-grub would hang when started with systemd?

Here is a successful normal run after booting with sysvinit:
$ sudo update-grub
Generating grub.cfg ...
Found background image: /usr/share/images/desktop-base/desktop-grub.png
Found linux image: /boot/vmlinuz-3.11-2-amd64
Found initrd image: /boot/initrd.img-3.11-2-amd64
Found linux image: /boot/vmlinuz-3.9-1-amd64
Found initrd image: /boot/initrd.img-3.9-1-amd64
Found linux image: /boot/vmlinuz-3.8-2-rt-amd64
Found initrd image: /boot/initrd.img-3.8-2-rt-amd64
Found linux image: /boot/vmlinuz-3.2.0-4-amd64
Found initrd image: /boot/initrd.img-3.2.0-4-amd64
Found linux image: /boot/vmlinuz-3.2.0-3-amd64
Found initrd image: /boot/initrd.img-3.2.0-3-amd64
  No volume groups found
Found Windows 7 (loader) on /dev/sda1
Found Windows 7 (loader) on /dev/sda2
done


When booting with systemd, the last line of the above that I see is as follows:
  No volume groups found

Then a Ctrl-C causes a few more lines to be displayed, and I repeat
this 3 more times to finally get back to a command prompt. Here is how
it goes under systemd:

$ sudo update-grub
Generating grub.cfg ...
Found background image: /usr/share/images/desktop-base/desktop-grub.png
Found linux image: /boot/vmlinuz-3.11-2-amd64
Found initrd image: /boot/initrd.img-3.11-2-amd64
Found linux image: /boot/vmlinuz-3.9-1-amd64
Found initrd image: /boot/initrd.img-3.9-1-amd64
Found linux image: /boot/vmlinuz-3.8-2-rt-amd64
Found initrd image: /boot/initrd.img-3.8-2-rt-amd64
Found linux image: /boot/vmlinuz-3.2.0-4-amd64
Found initrd image: /boot/initrd.img-3.2.0-4-amd64
Found linux image: /boot/vmlinuz-3.2.0-3-amd64
Found initrd image: /boot/initrd.img-3.2.0-3-amd64
  No volume groups found
^Cgrep: /tmp/os-prober.kY4cAH/raided-map: No such file or directory
grep: /tmp/os-prober.kY4cAH/swaps-map: No such file or directory
grep: /tmp/os-prober.kY4cAH/mounted-map: No such file or directory
^Cgrep: /tmp/os-prober.kY4cAH/raided-map: No such file or directory
grep: /tmp/os-prober.kY4cAH/swaps-map: No such file or directory
grep: /tmp/os-prober.kY4cAH/mounted-map: No such file or directory
^Cgrep: /tmp/os-prober.kY4cAH/raided-map: No such file or directory
grep: /tmp/os-prober.kY4cAH/swaps-map: No such file or directory
grep: /tmp/os-prober.kY4cAH/mounted-map: No such file or directory
grep: /tmp/os-prober.kY4cAH/raided-map: No such file or directory
grep: /tmp/os-prober.kY4cAH/swaps-map: No such file or directory
grep: /tmp/os-prober.kY4cAH/mounted-map: No such file or directory
^Cgrep: /tmp/os-prober.kY4cAH/raided-map: No such file or directory
grep: /tmp/os-prober.kY4cAH/swaps-map: No such file or directory
grep: /tmp/os-prober.kY4cAH/mounted-map: No such file or directory

$

Any guidance appreciated,
Zenaan