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Re: [Xen-devel] [PATCH][VT] No DISALLOW pte bit check for VMX domain

To: "Li, Chengyuan" <chengyuan.li@xxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH][VT] No DISALLOW pte bit check for VMX domain
From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
Date: Mon, 12 Sep 2005 15:15:19 +0100
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On 12 Sep 2005, at 14:55, Li, Chengyuan wrote:

You are right. For VMX guest, we need care PAT bit, though we needn't care GLOBAL bit.

Not sure what you mean -- maybe that the GLOBAL bit is ignored in guest VMCS, or that global entries are automatically flushed when transitioning?

Well, for now I would just apply the DISALLOW_MASK before calling get_page_from_l1e. Missing the global bit cannot harm performance since we need to transition into Xen (and hence flush global entries) when the guest switches its %cr3 anyway.

 -- Keir


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