From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: Interaction between Xen and XFS: stray RW mappings
Date: Mon, 22 Oct 2007 11:32:57 -0700
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To: dean gaudet <dean@arctic.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>, Xen-devel <xen-devel@lists.xensource.com>, =?ISO-8859-1?Q?Morten_?=, David Chinner <dgc@sgi.com>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, =?ISO-8859-1?Q?B=F8geskov?= <xen-users@morten.bogeskov.dk>, xfs@oss.sgi.com, xfs-masters@oss.sgi.com, Mark Williamson <mark.williamson@cl.cam.ac.uk>
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dean gaudet wrote:
> sounds like a bug in xen to me :)
>   

I explained at the head of this thread how and why Xen works in this
manner.  It's certainly a change from native execution; whether you
consider it to be a bug is a different matter.

But it turns out that leaving stray mappings around on pages which get
later used in special ways is a bad idea, and can manifest in all kinds
of random unpleasant ways.  Getting a clear error out of Xen is probably
nicest way to discover and debug this problem.

    J