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To: msch@snafu.de
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Sat, 10 May 2003 12:25:53 +0200."
             <200305101225.53877.msch@snafu.de> 
Date: Sat, 10 May 2003 15:45:01 +0200
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cc: freebsd-current@freebsd.org
Subject: Re: GEOM loose end? 
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In message <200305101225.53877.msch@snafu.de>, Matthias Schuendehuette writes:
>Hello phk,
>
>On Friday 09 May 2003 22:14, Poul-Henning Kamp wrote:
>> [...]
>> The very reason why you need to set a debug flag in geom is that
>> libdisk sneaks under the entire GEOM stack when it writes its changes
>> to the disk, and the kernel/GEOM has not been and will not be bloated
>> with code to detect this hack.
>> [...]
>> Unfortunately, I don't have time to work much on this issue, just
>> getting the kernel side and the basic tools (bsdlabel(8), sunlabel(8)
>> etc in shape takes most of the time I have.
>
>Perhaps a side issue - is it possible to tell the GRUB-people how to 
>deal with GEOM correctly?

I think the most compact clue I can offer is this:  The "trick" centers
on the rawoffset variable in the g_bsd_modify() routine in geom_bsd.c

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.