Comment 40 for bug 1024383

On 5/17/2013 8:17 AM, Phillip Susi wrote:
> You don't seem to have understood the passage you quoted. Let me try
> rephrasing it: when you boot from the livecd and update grub, you
> first chroot into the hard drive, so you are running the update-grub
> version on the hd, not the cd.

True, looking back through it, I think I misinterpreted it. I took the
original idea to be "use the mode (UEFI vs BIOS) which was used for this
current boot session". You can generate a grub.cfg for another system
without needing to chroot. grub-mkconfig lets you redirect the output to
any file you want. So, what's to prevent a user from booting a recovery
CD and, without using chroot, using:

grub-mkconfig -o /media/MyRealUbuntuPartition/boot/grub/grub.cfg

> We're not going to support having both installed at the same time and
> using the same config. You need to pick which mode you want to use
> and stick with it, not flip flop every other boot. In addition,
> Windows can not be booted in bios mode on a GPT disk, so you have to
> use grub-efi anyhow.

But other OS's *can*. I can boot my linux partitions in UEFI or BIOS
mode. Furthermore, linux is what I turn to when I have trouble booting
any of my partitions. If I can just get to a linux prompt, with
fdisk/parted/grub/etc, then I can usually fix any other booting
problems. So, it would be helpful to be able to boot a linux partition
from BIOS mode if the EFI SP gets hosed. You can choose not to support
that; that's your choice, but I think there are scenarios wherein it
would be useful.