From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xensource.com>
Subject: Re: [PATCH] Proper use of VMX execution controls MSR.
Date: Thu, 29 Mar 2007 10:11:58 +0100
Message-ID: <C231416E.C779%keir@xensource.com>
References: <B30DA1341B0CFA4893EF8A36B40B5C5DF223D5@pdsmsx411.ccr.corp.intel.com>
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To: "Li, Xin B" <xin.b.li@intel.com>, xen-devel@lists.xensource.com
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On 29/3/07 09:37, "Li, Xin B" <xin.b.li@intel.com> wrote:

> if we have the feature support in Xen, we should set the input control
> bit, and expect the adjusted value to be 1;
> if we don't have the feature support in Xen, we should clear the input
> control bit, and expect adjusted value to be 0;
> That's meaning the adjusted output is determined by the input control.
> So the expression should be "AND (msr_hi XOR msr_lo)".

The subsequent AND with msr_hi and the OR with msr_lo has exactly the same
effect. So the AND (msr_hi XOR msr_lo) is not incorrect, but it is
redundant.

 -- Keir