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[Xen-devel] Re: [PATCH] [HVM] Fix lmsw handling

To: Trolle Selander <trolle.selander@xxxxxxxxx>, xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: [Xen-devel] Re: [PATCH] [HVM] Fix lmsw handling
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Fri, 27 Jun 2008 17:23:57 +0100
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I applied it, but then realised that additionally LMSW can only affect bits 0-3 of CR0. Additionally SMSW emulation is wrong because it is only limited to 16-bit operation when the destination operand is memory. So I’ve fixed up these things in a subsequent changeset.

 -- Keir

On 27/6/08 14:11, "Trolle Selander" <trolle.selander@xxxxxxxxx> wrote:

The lmsw instruction can be used to set CR0_PE, but can never clear it, once set. Currently, as far as I can see, there is no provision to keep lmsw from clearing CR0_PE, either in the vmx code or in x86_emulate code (which is used by SVM to emulate lmsw). This patch fixes this issue.

Signed-off-by: Trolle Selander <trolle.selander@xxxxxxxxxxxxx>


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