From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mick Jordan <Mick.Jordan@sun.com>
Subject: Re: memory_reservation bug?: memory holes
Date: Wed, 11 Mar 2009 12:50:33 -0700
Message-ID: <49B81609.8070305@Sun.COM>
References: <C5DDAE97.4D02%keir.fraser@eu.citrix.com>
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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.

Mick