From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [V3 PATCH 7/9] x86/hvm: pkeys,
 add pkeys support for guest_walk_tables
Date: Thu, 10 Dec 2015 18:59:11 +0000
Message-ID: <5669CB7F.8080206@citrix.com>
References: <1449479780-19146-1-git-send-email-huaitong.han@intel.com>
	<1449479780-19146-8-git-send-email-huaitong.han@intel.com>
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To: Huaitong Han <huaitong.han@intel.com>, jbeulich@suse.com, jun.nakajima@intel.com, eddie.dong@intel.com, kevin.tian@intel.com, george.dunlap@eu.citrix.com, ian.jackson@eu.citrix.com, stefano.stabellini@eu.citrix.com, ian.campbell@citrix.com, wei.liu2@citrix.com, keir@xen.org
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On 07/12/15 09:16, Huaitong Han wrote:
> +
> +    /* PKRU dom0 is always zero */
> +    if ( likely(!pte_pkeys) )
> +        return 0;

This is not an architectural restriction (as far as I can tell).  Xen
must never make assumptions about how a guest chooses to use a feature.

~Andrew