From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH] KVM: x86: Add instruction length to VCPU event state
Date: Sat, 13 Feb 2010 12:21:47 +0200
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Cc: Marcelo Tosatti <mtosatti@redhat.com>, kvm <kvm@vger.kernel.org>
To: Jan Kiszka <jan.kiszka@web.de>
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On 02/13/2010 11:51 AM, Jan Kiszka wrote:
> From: Jan Kiszka<jan.kiszka@siemens.com>
>
> VMX requires a properly set instruction length VM entry field when
> trying to inject soft exception and interrupts. We have to preserve this
> state across VM save/restore to avoid breaking the re-injection of such
> events on Intel. So add it to the new VCPU event state.
>
>    

Can't we fake it?  set instruction length to 1 and rewind rip by 1.

The only case where I think this can fail is if we have a fault during 
the soft exception injection.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.