[LinuxBIOS] Using GRUB as a payload

Stefan Reinauer stepan at coresystems.de
Mon Sep 25 00:47:19 CEST 2006

* Al Boldi <a1426z at gawab.com> [060924 21:14]:
> > why would you want to "load an mbr" if you can easily read files from
> > all kinds of existing filesystems as well?
> Modularization.

With parsing filesystems you can load any modules directly from a

> So maybe leave the bootloader chainloaded as a separate module from the 
> block-driver.
In theory possible but fragile. Of course you can load any number of
intermediary loaders from disk.

> > No, "a simple MBR chainloader" is not all that is needed. The code that
> > you will find in an MBR will do bios callbacks, and you need to answer
> > those, or you will jump to nirvana.
> Ok, that's why we need a block-driver to chainload the MBR.
No, the block driver is there. It is Grub/LILO itself that calls 16bit
bios code. And LinuxBIOS doesnt have 16bit bios code.
This has nothing to do with a block driver.

> > What is your requirement? Loading Windows?
> Loading Linux, on an i440bx with a brain-dead AwardBIOS that can't boot USB, 
> nor can it boot disks >32GB.  

> Filo does the trick, but has its issues wrt 
> APM and its inability to remember boot commands like LiLo can.
How does APM come into play here?!?

So one requirement is: - remembering boot commands. 
So you want to choose which OS to boot on the next reset?

This is a 3 liner patch to FILO..

> Would chainloading LiLo be possible?

No, as I mentioned. Its a 16bit bootloader that requires a 16bit bios.
(Or ADLO.)

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