On Wed, Sep 22, 2010 at 03:16:24PM -0400, Patrick Doyle wrote: > I don't know where to turn here. It seems that every thread I've > found that describes this ends with "and now it works", but I can't > seem to get there. > > I have installed 64-bit Ubuntu 10.04 on a Macbook5,2. I would like to > boot this without the acpi=off parameter that is currently required. > Once, in the past, I installed grub-efi in the /efi folder and was > able to boot a 32-bit Ubuntu installation on this hardware. But I > have since installed the 64-bit version and can no longer get it to > boot. It gets as far as displaying the message about loading initrd > and stops there.
Unlike on BIOS systems, on EFI systems the bit length of the kernel must match the bit length of the firmware (at least on Linux; Vladimir tells me that the XNU kernel in Darwin does some horrible things to work around this restriction). Thus there are two possibilities: 1) You have 32-bit EFI, and won't be able to boot a 64-bit kernel from it. 2) You have 64-bit EFI, and your previous 32-bit kernel was actually silently falling back to BIOS compatibility mode. In either case, I'd recommend trying an ordinary BIOS version of GRUB instead (i.e. the grub-pc package); you'll need to create a BIOS Boot Partition (http://grub.enbug.org/BIOS_Boot_Partition), install GRUB to that partition rather than to the MBR, and tell rEFIt to boot from that partition. -- Colin Watson [cjwat...@ubuntu.com] _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org http://lists.gnu.org/mailman/listinfo/grub-devel