From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wei Huang <wei.huang2@amd.com>
Subject: Re: [PATCH] Fix save/restore of guest PAT table in HAP
 paging mode.
Date: Thu, 12 Apr 2012 01:14:59 -0500
Message-ID: <4F8672E3.80302@amd.com>
References: <CAKpvNa2wr3WUTEYuX9f5nKXGAEbxFxH1fgScS3z9iaCZ4Jdovg@mail.gmail.com>
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To: Gianluca Guida <glguida@gmail.com>
Cc: xen-devel@lists.xensource.com, Gianluca Guida <gianluca.guida@citrix.com>
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On 04/11/2012 06:04 PM, Gianluca Guida wrote:
> Hello,
>
> HAP paging mode guests use direct MSR read/write into the VMCS/VMCB
> for the guest PAT table, while the current  save/restore code was
> accessing only the pat_cr field in hvm_vcpu, used when intercepting
> the MSR mostly in shadow mode (the Intel scenario is a bit more
> complicated).
> This patch fixes this issue creating a new couple of hvm_funcs,
> get/set_guest_pat, that access the right PAT table based on the paging
> mode and guest configuration.
>
> As a major caveat, I haven't tested this patch on AMD, for lack of hardware.
I can test it on my AMD box tomorrow. BTW from my understanding, this 
patch doesn't have performance implication for nested paging mode, does it?

-Wei
>
> Signed-off-by: Gianluca Guida<gianluca.guida@citrix.com>