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From: Wei Huang <wei.huang2@amd.com>
To: Gianluca Guida <glguida@gmail.com>
Cc: xen-devel@lists.xensource.com,
	Gianluca Guida <gianluca.guida@citrix.com>
Subject: Re: [PATCH] Fix save/restore of guest PAT table in HAP paging mode.
Date: Thu, 12 Apr 2012 01:14:59 -0500	[thread overview]
Message-ID: <4F8672E3.80302@amd.com> (raw)
In-Reply-To: <CAKpvNa2wr3WUTEYuX9f5nKXGAEbxFxH1fgScS3z9iaCZ4Jdovg@mail.gmail.com>

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>

  reply	other threads:[~2012-04-12  6:14 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-04-11 23:04 [PATCH] Fix save/restore of guest PAT table in HAP paging mode Gianluca Guida
2012-04-12  6:14 ` Wei Huang [this message]
2012-04-12  7:32   ` Gianluca Guida
2012-04-13 16:29     ` Huang2, Wei
2012-04-13 17:08       ` Gianluca Guida
2012-04-13 17:51         ` Tim Deegan
2012-04-13 18:42         ` Wei Huang

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