From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <jbeulich@novell.com>
Subject: Re: machine check support in HVM guests
Date: Mon, 27 Nov 2006 14:59:45 +0000
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To: Keir Fraser <keir@xensource.com>
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>No, I'm not saying that. I was simply expecting that it would be easy to
>fake out a very minimal machine-check emulation where nothing ever goes
>wrong. :-) If that involves GPFing on some MSR accesses, those are easy to
>inject into an HVM guest I believe.

That wasn't my concern, I know that's simple. But the guest may not be
prepared to handle a GP fault here - after all, if CPUID says MCA is
supported, there is no reason the guest should use recovery methods
around accessing the respective MSRs. Likewise, if returning zero, the
guest may BUG(), as it may (validly) assert there's at least one bank of
MSRs supported. And so on...

Jan