kern/72812: GBDE, problems using gbde_swap

[Jean-Yves Lefort]

The following reply was made to PR kern/72812; it has been noted by GNATS.

From: Jean-Yves Lefort <jylefort at brutele.be>
To: freebsd-gnats-submit at FreeBSD.org, bln at deprese.net
Cc:  
Subject: Re: kern/72812: GBDE, problems using gbde_swap
Date: Tue, 26 Oct 2004 11:30:29 +0200

 Exactly the same problem here (5.3-BETA6).
 
 However, I managed to make the system bootable again by booting with
 the fixit floppy and issuing "disklabel -B ad0s1".
 
 Apparently the bde swap partition overwrote the bootstrap code of the
 slice. This problem is severe, /etc/rc.d/gbde_swap should *REFUSE* to
 enable a bde swap until it is fixed.
 
 --- output of "fdisk ad0" -----------------------------------------------------
 ******* Working on device /dev/ad0 *******
 parameters extracted from in-core disklabel are:
 cylinders=26354 heads=16 sectors/track=63 (1008 blks/cyl)
 
 Figures below won't work with BIOS for partitions not in cyl 1
 parameters to be used for BIOS calculations are:
 cylinders=26354 heads=16 sectors/track=63 (1008 blks/cyl)
 
 Media sector size is 512
 Warning: BIOS sector numbering starts with sector 1
 Information from DOS bootblock is:
 The data for partition 1 is:
 sysid 165 (0xa5),(FreeBSD/NetBSD/386BSD)
     start 63, size 26564769 (12971 Meg), flag 80 (active)
 	beg: cyl 0/ head 1/ sector 1;
 	end: cyl 1023/ head 223/ sector 63
 The data for partition 2 is:
 <UNUSED>
 The data for partition 3 is:
 <UNUSED>
 The data for partition 4 is:
 <UNUSED>
 --- end -----------------------------------------------------------------------
 
 --- output of "disklabel ad0s1" -----------------------------------------------
 # /dev/ad0s1:
 8 partitions:
 #        size   offset    fstype   [fsize bsize bps/cpg]
   a: 22370465  4194304    4.2BSD     1024  8192    16 
   b:  1048576        0      swap                    
   c: 26564769        0    unused        0     0         # "raw" part, don't edit
   e:  3145728  1048576    4.2BSD        0     0     0 
 --- end -----------------------------------------------------------------------
 
 Mounts:
 	ad0s1a as /
 	ad0s1e as /var
 
 -- 
 Jean-Yves Lefort
 
 jylefort at brutele.be
 http://lefort.be.eu.org/