From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: [PATCH] retry instruction on svm emulation failure
Date: Wed, 18 May 2011 11:08:30 +0100
Message-ID: <C9F9592E.1A832%keir.xen@gmail.com>
References: <8605c877b972c82a3859.1305708728@yakj.usersys.redhat.com>
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To: Paolo Bonzini <pbonzini@redhat.com>, xen-devel@lists.xensource.com
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On 18/05/2011 10:05, "Paolo Bonzini" <pbonzini@redhat.com> wrote:

> retry instruction on svm emulation failure
> 
> Upon emulation failure, Xen injects a #GP into the guest on AMD machines.
> However, this kind of #GP does not happen in hardware.  It is possible
> (and was observed in practice) that the failure is transient.  It will
> go away naturally if the instruction is retried, because the guest will
> be executing other code and will not exit.

It begs the question why we were emulating the instruction in the first
place. I'd like to see further explanation, with a concrete example, before
applying this patch. Or get an Ack from an AMD maintainer.

 -- Keir