From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <jbeulich@novell.com>
Subject: Re: [PATCH] x86: machine check exception handling
Date: Fri, 22 Jun 2007 07:57:22 +0100
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To: xen-devel@lists.xensource.com, Keir Fraser <keir@xensource.com>
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> 3. Most contentious, I'm sure: removed VMX changes that would keep
>interrupts disabled across NMI/MCE. The reason is simply that SVM does =
not
>bother with this. If there is a requirement that NMI/MCE be called with
>particular constraints on EFLAGS, then we should make that clear and fix =
up
>both VMX and SVM in a separate patch. The pain of this is that it would
>probably require extra checks on critical vmexit paths. Is it *really* =
that
>bad for #MC to get interrupted?

Yes, I think it is bad - the machine is known to be a in bad condition =
already,
and by allowing external interrupts you make the situation even worse.
Consequently I think SVM should be fixed to only conditionally enable
interrupts, just like VMX does.

Jan