From owner-freebsd-current@FreeBSD.ORG  Thu Oct 20 06:51:36 2005
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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, 20 Oct 2005 08:33:03 +0200."
	<20051020063303.GA19624@garage.freebsd.pl> 
Date: Thu, 20 Oct 2005 08:51:33 +0200
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Cc: Brian Fundakowski Feldman <green@FreeBSD.org>,
	FreeBSD current mailing list <current@FreeBSD.org>,
	"Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net>
Subject: Re: mount memory modified after free 
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In message <20051020063303.GA19624@garage.freebsd.pl>, Pawel Jakub Dawidek writ
es:

>Bascially there is only one place to store mount-point's
>vnode in device structure (IIRC) and if you mount the same provider twice,
>it will be overwritten and you'll not be able to unmount first file system
>without panicing.

There is more, you also need to cope with the UFS snapshot data hung
off the cdev etc.


-- 
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.