From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xensource.com>
Subject: Re: Re: [PATCH] make ballooning up to maxmem work
Date: Wed, 22 Nov 2006 11:18:39 +0000
Message-ID: <C189E28F.4DF0%keir@xensource.com>
References: <20061122104021.GA2496@redhat.com>
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To: Glauber de Oliveira Costa <gcosta@redhat.com>, Rik van Riel <riel@redhat.com>
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On 22/11/06 10:40, "Glauber de Oliveira Costa" <gcosta@redhat.com> wrote:

>>      case XENMEM_current_reservation:
>>      case XENMEM_maximum_reservation:
>> +    case XENMEM_maximum_memory:
>>          if ( copy_from_guest(&domid, arg, 1) )
>>              return -EFAULT;
> 
> This still makes use of d->max_pages in return. Isn't it supposed to
> change in the future too? IIRC, according to Keir, max_pages will track
> the _current_ number of pages, differing from tot_pages only in a brief
> timeframe in which you balloon, but tot_pages was not yet updated.

This adds a level of indirection at least, but really we may as well
implement the XENMEM_memory_map hypercall. Then there is no guest
modification required.

 -- Keir