From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pascal Bellard <pbellard@lucent.com>
Subject: Re: Elks Distribution
Date: Tue, 28 May 2002 16:30:48 +0000
Sender: linux-8086-owner@vger.kernel.org
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To: Javier Sedano <jsedano@dit.upm.es>
Cc: Linux 8086 <linux-8086@vger.kernel.org>

Javier Sedano wrote:
> 
> Pascal Bellard wrote:
> >
> > Yes. It can chain any boot-record and support FAT filesystem but
> > doesn't boot msdos kernel directly.
> >
> 
>         Can it also been "chained"? I mean... I've goot Minix monitor installed
> to boot Minix and MSDOS, and I'd like to install bootkit on bda3 and use
> Minix monitor to chain boot bootkit.

I don't know the Minix monitor.

Bootkit bootblock needs the drive number in DL register only.

Note that the partition offset (0 with floppy) is hardcoded in bootblock
by the installer. i.e. if you get the bootblock of partition 3,
(# dd if=/dev/hda3 of=/boot/bootminix bs=1024 count=1), /boot/bootminix
will always boot partition 3 assuming dl register is correct.

1- chained: Bootkit bootblock needs only DL register
2- chaining: Bootkit bootblock restores CX, DX, SI, DI, BP and set:
   CS=DS=ES=SS=0 IP=7C00 SP=7C00 FLAGS.D=0 FLAGS.I=1

-pascal