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Re: [Xen-devel] memory_reservation bug?: memory holes

To: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] memory_reservation bug?: memory holes
From: Mick Jordan <Mick.Jordan@xxxxxxx>
Date: Wed, 11 Mar 2009 12:50:33 -0700
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On 03/11/09 11:08, Keir Fraser wrote:

Just because you called decrease_reservation() doesn't mean the pages
necessarily really got freed. If you still have mappings to them squirrelled
away then the free can be deferred.
A related question. I assume it is ok to have holes in the physical memory, i.e. call decrease_reservation with a range << max_pfn. In this case, what are the rules for the value in the P2M table? Does Xen zero out the slot or is it the guest's responsibility? save/restore must be able to determine that a hole exists.


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