ubiquity is trying to unmount /cdrom when committing changes to the partition table

I think this check is generally correct, as if you actually need to commit real changes to that partition table then the kernel will be unable to do so while /cdrom is mounted from a partition within it. However, I'll add a preseedable question to let you skip this in special cases.

The fix I've committed is a workaround; Evan, if you have more you're looking at that's still relevant when you get back from holiday, feel free to reopen this. I'm conscious that if this is going to work at all then something in the partitioner's busy/changed detection must be wrong!

This bug was fixed in the package ubiquity - 1.9.8

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ubiquity (1.9.8) intrepid; urgency=low

  [ Mario Limonciello ]
  * Remove xmltv and dvbutils options, as they will be installed across
    all boxen now.
  * debian/control:
    - Drop depends for guidance on mythbuntu package.
  * Install custom mythbuntu recipe - only applicable for Mythbuntu
    frontend.
  * Add support for additional mythbuntu plugin, apple trailers.

  [ Colin Watson ]
  * When copying files, remove regular files and symlinks if they exist
    already on the target; this can happen legitimately if installing over
    an existing system and /boot wasn't erased.
  * Make the Back button insensitive on the first page rather than hiding it
    (LP: #186953).
  * Rename main Cancel button to Quit, and adjust the quit dialog text
    slightly so that we consistently use "quit" as the action verb and
    "cancel" clearly means to cancel the dialog (LP: #45690).
  * Fix format string substitution error in _abstract method.
  * Allow skipping the unmounting of busy partitions by preseeding
    ubiquity/partman-skip-unmount to true (LP: #252667).
  * Automatic update of included source packages: debian-installer-utils
    1.59ubuntu2, grub-installer 1.32ubuntu2, partman-target 55ubuntu2.

  [ Evan Dandrea ]
  * Also remove the langlevel file if it exists before we start
    localechooser.

 -- Colin Watson <email address hidden> Fri, 08 Aug 2008 16:10:49 +0100