Comment 29 for bug 1237519

Igor: Thanks for your suggested grub-installer patches. There were a few problems with it, mainly misunderstandings about exactly what semantics were expected of various code paths, and the patch would have mishandled /dev/fiob* and later devices. I've uploaded a corrected (I think) version to https://launchpad.net/~cjwatson/+archive/grub/+packages for trusty.

Narinder: The use of "dummy" is correct. The problem you were encountering was because you dropped a grub-installer version from precise directly into a raring installer, and as a result you reverted the fix for bug 1054323 along the way. Needless to say I don't recommend this approach. :-)

Kent: The reason that regex is failing is that patching grub-installer isn't enough; it's also necessary to patch GRUB itself to handle probing these devices. grub2 2.00-19ubuntu4~ppa1 in https://launchpad.net/~cjwatson/+archive/grub/+packages should have the necessary patch.

There is now the slightly fiddly question of how to test all this. I'd very much like to test this on trusty before uploading backported patches to precise. However, this will only work if you've resolved the issues with newer kernels. If not, please let me know and I'll prepare versions for precise. If you can manage to use trusty, then the simplest way to test it is probably to do the following:

 * Boot the installer with the following in its preseed file:

  d-i apt-setup/local0/repository string http://ppa.launchpad.net/cjwatson/grub/ubuntu trusty main
  d-i apt-setup/local0/key string http://keyserver.ubuntu.com/pks/lookup?op=get&search=0x6A547A8B977102C0

 * Run through the installer until after the "Loading additional components" stage.

 * Switch to tty2 (Alt-F2), run "nano /usr/bin/grub-installer", and manually apply the grub-installer part of the change in https://launchpadlibrarian.net/156124415/grub-installer_1.78ubuntu8_1.78ubuntu9~ppa1.diff.gz to that file; the change is short enough that you can do this in place with a bit of care. Save (Ctrl-o) and exit (Ctrl-x).

 * Switch back to tty1 (Alt-F1) and continue installation.