From owner-freebsd-geom@FreeBSD.ORG  Thu Nov 15 07:53:44 2007
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To: Pawel Jakub Dawidek <pjd@FreeBSD.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Thu, 15 Nov 2007 08:46:47 +0100."
	<20071115074647.GB80222@garage.freebsd.pl> 
Date: Thu, 15 Nov 2007 07:53:41 +0000
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Cc: Eric Anderson <anderson@FreeBSD.org>, freebsd-geom@FreeBSD.org,
	Ivan Voras <ivoras@FreeBSD.org>, Gordon Tetlow <gordon@tetlows.org>
Subject: Re: Disk mounting in recent Linuxes 
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In message <20071115074647.GB80222@garage.freebsd.pl>, Pawel Jakub Dawidek writ
es:

>The problem is that when you have two colliding providers (with the same
>name) you are already in very bad position, because no matter what you
>do you may end-up with system not booted properly.

Originally, I thought about disabling all colliding providers,
provided none of them were open, simply as a matter of prudence.

But that doesn't work for N reasons, the most important one being
that you may not be able to correct the situation if you can't get
at at least one of the colliding providers.

So the current semantics, as implemented by GEOM and DEVFS is that
all colliding providers appear, but if you try to open the shared
name, you get the first one all the time.

-- 
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.