From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tim Deegan <tim@xen.org>
Subject: Re: [PATCH 7 of 7] x86/mm: When removing/adding a page
	from/to the physmap, keep in mind it could be shared
Date: Fri, 10 Feb 2012 15:38:08 +0000
Message-ID: <20120210153808.GC32107@ocelot.phlegethon.org>
References: <patchbomb.1328766345@xdev.gridcentric.ca>
	<667191f054c34b6c1e72.1328766352@xdev.gridcentric.ca>
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To: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Cc: george.dunlap@eu.citrix.com, andres@gridcentric.ca, xen-devel@lists.xensource.com, keir.xen@gmail.com, adin@gridcentric.ca
List-Id: xen-devel@lists.xenproject.org

At 00:45 -0500 on 09 Feb (1328748352), Andres Lagar-Cavilla wrote:
> When removing the m2p mapping it is unconditionally set to invalid, which
> breaks sharing.
> 
> When adding to the physmap, if the previous holder of that entry is a shared
> page, we unshare to default to normal case handling.
> 
> And, we cannot add a shared page directly to the physmap. Proper interfaces
> must be employed, otherwise book-keeping goes awry.
> 
> Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>

Acked-by: Tim Deegan <tim@xen.org>