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Re: [Xen-devel] Readonly memory for guest domain


  • To: <xen-devel@xxxxxxxxxxxxxxxxxxx>
  • From: "Peter Teoh" <htmldeveloper@xxxxxxxxx>
  • Date: Wed, 12 Sep 2007 11:15:02 +0800
  • Delivery-date: Tue, 11 Sep 2007 20:15:41 -0700
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  • List-id: Xen developer discussion <xen-devel.lists.xensource.com>

Sorry, I think may have found the answer.   The real answer is because the guest should be hidden from the real physical PTE page table mapping.   And since all the guest page table are faked, a mechanism is needed to inform the hypervisor to remap to the real physical mapping.   The mechanism present used to do this is setting the table to readonly, so as to trigger an exception whenever writing is attempted.
 
Not sure if my analysis is correct?
 
Thanks.
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