From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrea Arcangeli <aarcange@redhat.com>
Subject: Re: [PATCH v8 13/15] ARM: KVM: Handle guest faults in KVM
Date: Wed, 20 Jun 2012 19:49:27 +0200
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Cc: Avi Kivity <avi@redhat.com>, android-virt@lists.cs.columbia.edu,
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To: Christoffer Dall <c.dall@virtualopensystems.com>
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On Wed, Jun 20, 2012 at 11:13:36AM -0400, Christoffer Dall wrote:
> ah, we don't do things right, we use gfn_to_pfn() flat out and will
> always break the COW :)
> 
> I guess now, when change_pte is a nop, it's outright incorrect if
> anyone runs KSM.
> 
> This has just been added to my todo-list.

Great.

Either implement change_pte, or use gfn_to_pfn_async(write_fault=0)
for read faults.