From mboxrd@z Thu Jan  1 00:00:00 1970
From: George Dunlap <George.Dunlap@eu.citrix.com>
Subject: Re: mem_sharing: summarized problems when domain is dying
Date: Fri, 21 Jan 2011 16:41:47 +0000
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To: Jui-Hao Chiang <juihaochiang@gmail.com>
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Tim / Xiaoyun, do you think something like this might work?

 -George

On Fri, Jan 21, 2011 at 4:32 PM, George Dunlap <dunlapg@umich.edu> wrote:
> [sorry, accidentally sent too early]
>
> On Fri, Jan 21, 2011 at 4:29 PM, George Dunlap <dunlapg@umich.edu> wrote:
>> I'm not sure the exact rationale behind the "cannot fail" flag; but it
>> looks like in grant_table.c, both callers of gfn_to_mfn_unshare()
>> handle the case where the returned p2m entry is just
>
> ...invalid. =A0I wonder if "unsharing" the page, but marking the entry
> invalid during death would help.
>
> I suppose the problem there is that if you're keeping the VM around
> but paused for analysis, you'll have holes in your address space. =A0But
> just returning an invalid entry to the callers who try to unshare
> pages might work.
>
> =A0-George
>

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