From a4d2682238cd2e2d70d06640e9fa80f44c13c16d Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <eelco.dolstra@logicblox.com>
Date: Thu, 3 Nov 2011 02:15:33 +0000
Subject: [PATCH] * Remove loopback devices during shutdown, since they may
 prevent   filesystems from being unmounted.

svn path=/nixos/trunk/; revision=30203
---
 modules/system/upstart-events/shutdown.nix | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/modules/system/upstart-events/shutdown.nix b/modules/system/upstart-events/shutdown.nix
index cf06ba10d08b..32966f03cdba 100644
--- a/modules/system/upstart-events/shutdown.nix
+++ b/modules/system/upstart-events/shutdown.nix
@@ -88,6 +88,13 @@ with pkgs.lib;
               tryAgain=
               failed= # list of mount points that couldn't be unmounted/remounted
 
+              # Get rid of loopback devices.
+              loDevices=$(losetup -a | sed 's#^\(/dev/loop[0-9]\+\).*#\1#')
+              if [ -n "$loDevices" ]; then
+                  echo "removing loopback devices $loDevices..."
+                  losetup -d $loDevices
+              fi
+
               cp /proc/mounts /dev/.mounts # don't read /proc/mounts while it's changing
               exec 4< /dev/.mounts
               while read -u 4 device mp fstype options rest; do