grub-macbless does not create a bootable system

[John Paul Adrian Glaubitz]

Hello!

I have been toying around with grub-macbless in order to switch the GRUB
partition for PowerMacs running Debian from HFS to HFS+.

Currently, I we're stuck to HFS because the available »hattrib« tool for
blessing a bootloader for NewWorld Macs supports HFS only. »hatttrib« is
part of the hfsutils package [1].

In order to boot GRUB on an Apple PowerMac, it's first necessary to create
an HFS filesystem, then run »grub-install« and then bless the bootloader
directory [2]:

# mkfs.hfs /dev/sda2
# mkdir /boot/grub
# mount -thfs /dev/sda2 /boot/grub
# grub-install --macppc-directory=/boot/grub
# umount /dev/sda2
# hmount /dev/sda2
# hattrib -c UNIX -t tbxi :System:Library:CoreServices:BootX
# hattrib -b :System:Library:CoreServices
# humount

Supposedly, »grub-macbless« should be able to bless a boot directory as
well, but the following command will not create a bootable system:

# grub-macbless --ppc /boot/grub/System/Library/CoreServices

However, an HFS boot partition treated like this with »grub-macbless« does
not create a bootable system, even when running the »hattrib« command to
set the »tbxi« attribute on the »BootX« flag. So, it's currently not possible
to create a bootable GRUB partition on Apple PowerMac using just 
»grub-macbless«.

Also, in order to be able to replace »hattrib« from »hfsutils«, »grub-macbless«
should support both blessing a system directory as well as setting the »tbxi«
attribute on the stage1 bootloader »BootX«.

Adrian

> [1] https://www.mars.org/home/rob/proj/hfs/
> [2] 
> https://salsa.debian.org/installer-team/grub-installer/-/blob/a8b85210dfa37b894714e269ae323c2af2f23858/grub-installer#L1030

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer
`. `'   Physicist
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