Merge remote-tracking branch 'remotes/origin/pr/113'

diff --cc grml-debootstrap
index 1a3cda5,4670144..ab7c577
--- 1/grml-debootstrap
--- 2/grml-debootstrap
+++ b/grml-debootstrap
@@@ -1517,13 -1519,18 +1522,23 @@@ f
    umount "${MNTPOINT}"/sys
    umount "${MNTPOINT}"/dev/pts
    try_umount 3 "${MNTPOINT}"/dev
+ 
+ }
+ # }}}
+ 
+ # unmount VM image {{{
+ umount_target() {
+   if [ -z "${VIRTUAL}" ] ; then
+      return 0
+   fi
+ 
    umount "${MNTPOINT}"
    kpartx -d "${ORIG_TARGET}" >/dev/null
 +  # Workaround for a bug in kpartx which doesn't clean up properly,
 +  # see Debian Bug #891077 and Github-PR grml/grml-debootstrap#112
 +  if dmsetup ls | grep -q "^${LOOP_PART} "; then
 +    kpartx -d "/dev/${LOOP_DISK}" >/dev/null
 +  fi
  }
  # }}}