From: George Dunlap <george.dunlap@eu.citrix.com>
To: Jan Beulich <JBeulich@suse.com>
Cc: xen-devel <xen-devel@lists.xenproject.org>,
Eddie Dong <eddie.dong@intel.com>,
Jun Nakajima <jun.nakajima@intel.com>, Tim Deegan <tim@xen.org>
Subject: Re: PVH and mtrr/PAT.........
Date: Fri, 22 Nov 2013 12:16:42 +0000 [thread overview]
Message-ID: <528F4B2A.1010109@eu.citrix.com> (raw)
In-Reply-To: <528F496F0200007800105BFF@nat28.tlf.novell.com>
On 22/11/13 11:09, Jan Beulich wrote:
>>>> On 22.11.13 at 11:43, George Dunlap <george.dunlap@eu.citrix.com> wrote:
>> I'm not incredibly familiar with the PAT / MTRR stuff, either from a
>> hardware level or a Xen level, so sorry if this is a dumb question. It
>> sounds like you're saying, because we have virtual MTRRs that are
>> already translated into EPT types, we should disable virtual MTRRs and
>> use PAT instead. That doesn't make any kind of sense to me. (I didn't
>> understand it when Jan said it either.)
> The underlying observation is that MTRRs aren't really needed -
> all they can do can be done with PAT. They pre-date PAT though,
> hence hardware vendors can't easily drop them. But in a model
> like PVH I just don't see the value of allowing their use, considering
> that this adds unnecessary complexity.
OK -- so when we move forward with the plan of "PVH mode is HVM mode
with a couple of tweaks", you think that we should have an "enable
virtual MTRR" flag, and disable this for PVH mode?
-George
next prev parent reply other threads:[~2013-11-22 12:17 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-20 2:11 PVH and mtrr/PAT Mukesh Rathor
2013-11-20 7:22 ` Xu, Dongxiao
2013-11-20 8:42 ` Jan Beulich
2013-11-20 18:12 ` George Dunlap
2013-11-20 22:24 ` Mukesh Rathor
2013-11-21 15:47 ` George Dunlap
2013-11-21 23:41 ` Mukesh Rathor
2013-11-22 10:43 ` George Dunlap
2013-11-22 11:09 ` Jan Beulich
2013-11-22 12:16 ` George Dunlap [this message]
2013-11-22 12:30 ` Jan Beulich
2013-11-22 10:29 ` Jan Beulich
2013-12-03 7:20 ` Xu, Dongxiao
2013-12-03 13:54 ` George Dunlap
2013-11-21 2:42 ` Mukesh Rathor
2013-11-21 7:50 ` konrad wilk
2013-11-21 11:40 ` Jan Beulich
2013-11-22 0:42 ` Mukesh Rathor
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