From: Andi Kleen <ak@suse.de>
To: Zachary Amsden <zach@vmware.com>
Subject: Re: [RFC, PATCH 17/24] i386 Vmi msr patch
Date: Tue, 14 Mar 2006 18:43:23 +0100
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On Tuesday 14 March 2006 17:32, Zachary Amsden wrote:

> There aren't really any.  There are some unexpected ones - such as
> setting SYSENTER_CS during a context switch, but only if leaving v8086
> mode, which isn't a common case.  But most importantly, the MSR
> functions were challenging to get correct, because they combine two
> novel elements - 64 bit values, as well as non-C calling conventions.
> They were actually some of the first functions I inlined, because I knew
> there would be problems, and the solutions would yield more powerful
> inlining macros.

That doesn't seem like a good rationale to add it to the kernel.

>
> > And I don't think it's a good idea to virtualize the TSC
> > without CPU support.
>
> We currently don't support configurations without a TSC.  But we're not
> trying to virtualize the TSC without CPU support.  It is possible.  But
> I have no idea _why_ you would want to do such a thing.

Don't change it then?

BTW I think it will be pretty tough to find enough competent reviewers
for your patchkit.

And is the spec still in flux or are you trying to implement an interface
for an specification that is already put into stone? 

-Andi
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