Re: Starting grub 2 from grub legacy?

[Pavel Roskin <proski@gnu.org>]

On Tue, 2008-02-19 at 15:14 +0800, Bean wrote:

> That's because core.img is a.out format multiboot kernel, but the
> current multiboot loader can only handle elf format. My bsd patch add
> a.out support for multiboot. with that, you can load core.img
> successfully.

It's working, thanks!  Just one minor issue - the new core.img is
confused about the root device:

Welcome to GRUB!

error: unknown device
Entering into rescue mode...
grub rescue> set
prefix=(fd0,1,a)/boot/grub
root=fd0,1,a
grub rescue>


That's qemu with one hard drive and no floppies.  By the way, "Entering
into rescue mode" should be "Entering rescue mode".

> > grub> multiboot /boot/grub/stage2
> > alloc magic is broken at 0x93c50
> > Aborted. Press any key to exit.
> 
> stage2 is not multiboot format, actually, it's not of any format. The
> alloc magic broken is caused by a bug in the multiboot loader, my bsd
> also fit this, it will print the error message: "currently only ELF is
> supported"

Yes, it's better now.

Actually, GRUB 2 modules still confuse multiboot.  Loading _bsd.mod or
affs.mod would cause GRUB to hand.  But "multiboot configfile.mod"
actually crashed qemu 0.9.1 with "qemu: fatal: triple fault"!

> however, it's still possible to load GRUB Legacy with my grubutil
> package. It contain several header file which you can use to load
> various boot loader from any loader that support linux kernel. For
> example, the header for grub legacy is ldgrub.bin, you can use it like
> this:
> 
> linux ldgrub.bin
> initrd stage2

I'm thinking maybe the final GRUB 1 should make stage2 multiboot
compliant, if we are going to release it one day.

-- 
Regards,
Pavel Roskin