Testing needed for GRUB EFI support

Colin Watson cjwatson at ubuntu.com
Tue Jun 8 22:41:37 BST 2010

This mail is part of the work laid out in

Supporting EFI (including UEFI) firmware properly in Ubuntu may need to
involve delivering CD images that boot properly using both BIOS and EFI.
The way to do this is to use the support in the El Torito CD
specification for what are called "multi-catalog" images: booting with
EFI support if it's available, otherwise with BIOS support.

The corresponding Fedora specification says that, when they tried to do
this, they discovered problems on a number of quite current BIOS-based
systems which refused to boot from multi-catalog CDs.  I'd like to try
to find out a bit more about how widespread this is, and what kinds of
machines are affected, with the aim of deciding whether we can ship
multi-catalog Ubuntu CDs or whether we have to come up with some other
way to support EFI systems.

As such, I've put together a multi-catalog CD image using GRUB.  This
just contains GRUB images and modules for i386-pc, i386-efi, and
x86_64-efi, plus the example GRUB configuration file.  It doesn't
contain any kernels or anything like that, so none of the menu entries
will work.

What I'd like people to do is to download and burn to CD the following


First and foremost, I'd like to know whether it boots far enough to show
you the GRUB menu.  Secondly, please confirm which platform it used:
press 'c' at the GRUB menu, type 'echo $prefix', and show me the output.
After that, remove the CD and reboot back to your normal system.

I am interested in results from all of the following general categories
of x86 systems, both 32-bit and 64-bit:

 * BIOS (if you don't know, it's BIOS)
 * Intel-based Mac
 * Other EFI system

Please report results in the following format so that I can collate them

  System: [brief description of your system, with manufacturer and model]
  Boots from CD: [yes/no]
  $prefix when booted from CD: [result of 'echo $prefix']

Please e-mail results to me directly (cjwatson at ubuntu.com) and NOT to
the mailing list.  I'll post a summary of results after a while.


Colin Watson                                       [cjwatson at ubuntu.com]

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