From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: [PATCH 20 of 20] n2 MSR handling and capability
	exposure
Date: Thu, 02 Jun 2011 20:20:06 +0100
Message-ID: <CA0DA0F6.1B844%keir.xen@gmail.com>
References: <20110602151128.GQ5098@whitby.uk.xensource.com>
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To: Tim Deegan <Tim.Deegan@citrix.com>, Eddie Dong <eddie.dong@intel.com>
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On 02/06/2011 16:11, "Tim Deegan" <Tim.Deegan@citrix.com> wrote:

>> BTW, I don't really like defining all these REMOVED_* macros, each
>> of which is used only once a few lines from the definition (here and
>> elsewhere in the series).  It just adds clutter for no benefit.
>> 
> 
> Oh, I forgot to say: will this feature-blacklisting work over live
> migration to a machine with a different CPU?  There isn't an equivalnet
> of the CPUID masking feature to make all the machines in a cluster seem
> to have the same VMX features.
> 
> Elsewhere we use whitelisting for passsing hardware capability flags to
> HVM guests; I think we should use whitelists here too.

Blacklists create a total mess of doom. We should absolutely disallow the
creation of any new ones. I think HVM guests are currently clean in this
regard and should stay that way.

 -- Keir