EFI-dualbooting OSX and Linux on iMac with T7400-CPU

[Eeri Kask <Eeri.Kask@inf.tu-dresden.de>]

Hello,

After creating 4 partitions with MacOSX installation CD (and installing
OSX) I installed Gentoo 2006.1 x86_64 onto the 4th partition (i.e.
/dev/sda5; in OSX invisible FAT32 partition counts as /dev/sda1).
Now I am kindly looking for help in making linux EFI-bootable using grub2.

In short, what I did so far is (following instructions at
http://grub.enbug.org/TestingOnEFI as closely as I could):

running on CD-booted 64-bit Linux (on /dev/sda5 as root filesystem):

1) cvs -d:pserver:anonymous@cvs.savannah.gnu.org:/sources/grub checkout
grub2
2) cd grub2
3) ./configure --with-platform=efi
4) make
5) ./grub-mkimage -d . -o grub.efi gpt hfsplus fat ext2
6) cp grub.efi *.mod fs.lst command.lst  /boot/grub/
7) cp grub.efi *.mod fs.lst command.lst  /media/usbdisk/
8) I compiled 2.6.18.3 kernel as /boot/vmlinuz

Then I booted MacOS and as root-user:

9) mkdir /Volumes/something/efi/grub
10) Copied  usbstick/*  to  /Volumes/something/efi/grub/
11) bless --folder=/Volumes/something
--file=/Volumes/something/efi/grub/grub.efi --setBoot

12) Then I created  /Volumes/something/efi/grub/grub.cfg  as

set timeout=10
menuentry "GNU/Linux"
{
  search --set /boot/vmlinuz
  set root=(hd0,5)
  linux /boot/vmlinuz root=/dev/sda5
}
menuentry "MacOSX"
{
  set root=(hd0,2)
  chainloader /usr/standalone/i386/boot.efi


In fact 'something' is 'Macintosh HD part2', OSX formatted HFS+
journaled partition /dev/disk0s3.


Now if holding down the 'alt' key while powering on I can choose between
disk0s2 with installed OSX and 'EFI_boot' (disk0s3) which loads and
starts grub if selected.

Grub comes and gives lots of errors:

(line 2-2)
syntax error
Incorrect command
...
(line 12-12)
Press any key to continue...

Then grub shows command line interface:

grub> set root=(hd0,5)
grub> linux /boot/vmlinuz root=/dev/sda5
grub> boot
grub> _

is what I entered and now nothing happens.  However grub reads the
ext3-formatted /dev/sda5 partition as typing TAB completes path- and
filenames.

I am very thankful if someone could point out what is wrong I have done
above.  I have zero experience in using MacOSX but I think the 'bless'
was successful as OSX presents boot device where grub was copied.
Second, I suspect I probably can't boot "MacOSX"-entry above because I
could not figure out if grub can read files in HFS+ journaled partitions
(maybe this is why grub shows syntax errors?); but I can happily live
with pressing 'alt' key while turning power on.

Greetings  (I am sorry for the long post),

    Eeri Kask