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From: rommel@Informatik.TU-Muenchen.DE (Kai-Uwe Rommel)
Newsgroups: comp.os.minix
Subject: Re: Small Boot Package from Rigid Disk (caution !!! bugs)
Keywords: IBM_PC, Hard Disk Boot
Message-ID: <1991May10.115809.7101@Informatik.TU-Muenchen.DE>
Date: 10 May 91 11:58:09 GMT
References: <1991May7.013515.14634@sobeco.com>
Sender: news@Informatik.TU-Muenchen.DE
Organization: Technische Universitaet Muenchen, Germany
Lines: 26

This harddisk boot package has two problems/bugs (I have just tried it
out).

1. insert was unable to insert the hd_image on my /dev/hd2 which is
   32000 blocks in size with 760 blocks left unused behind it on the
   partition. It said something of an negative value of sectors to skip.
   Probably an integer overflow. Inserting the hd_image into my /dev/hd3
   worked which is only 3840 blocks with 444 blocks unused behind it.

2. When booting, hd_boot said "Bad magic number" because it assumed the
   base of the partition to be less than 65536 (as documented in the
   source !!!) but my /dev/hd3 starts at 311472 (cylinder 618 with 14
   heads and 36 sectors/track, a 200MB IDE drive). Thus it read
   something out of my DOS partition :-) that did not look like a minix 
   file system.

I think these bugs are easy to fix, I will do it when returning from the
weekend. Otherwise the hd_boot can only used with the boot partition
within the first 32M of the disk and rather small partitions.

Kai Uwe Rommel

/* Kai Uwe Rommel, Munich ----- rommel@lan.informatik.tu-muenchen.dbp.de */

DOS ... is still a real mode only non-reentrant interrupt
handler, and always will be.                -Russell Williams