2012/9/29 Andrey Borzenkov <arvidjaar@gmail.com>

> Attached are suggested implementation for UEFI support. Because ESP can
> contain arbitrary number of boot entries, it is itself implemented as
> extensible framework.
>
> 1. /usr/lib/os-prober/mounted/05efi
>
> Makes basic plausibility checks (FAT and /EFI exists) and calls scripts
> from /usr/lib/os-prober/mounted/efi/* to perform OS detection. Returns
> detected bootladers in the form ${device}@${path}:${long}:${short}:efi
>
> 2. patch for /etc/grub.d/30_os-prober
>
> creates "chainloader ${path}" entry from the above
>
> 3. Patch for /usr/lib/os-prober/mounted/20microsoft
>
> It seems that on UEFI systems Windows sometimes installs both legacy and
> UEFI bootloader. In this case os-prober adds menu entries for legacy
> Windows boot which do not work from within UEFI GRUB bootloader. Patch
> detects UEFI platform and skips running there.
>
> 4. /usr/lib/os-prober/mounted/efi/20microsoft
>
> Suggested implementation for Microsoft bootloader. We have no way to
> create entries for individual OSes here (this would involve parsing BCD
> store at the very least), so entry is titled as "Windows Boot Manager",
> the same as is automatically added to UEFI boot menu.
>
> This is successfully tested on VM with Windows 7/openSUSE 12.2 dual
> boot. As openSUSE 12.2 comes with GRUB2 as default bootloader, this
> issue seems to be hit by quite a number of users.
>
> Comments?
>
> -andrey
>

Thanks Andrey for working on this.
- I confirm that Windows sometimes installs both Legacy and UEFI bootloader.
Example: http://paste.ubuntu.com/1248333
- For information, here is a report you may be interested in:
https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1024383

Regards
Yann