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From:   Vitaly Kuznetsov <vkuznets@redhat.com>
To:     Jim Mattson <jmattson@google.com>
Cc:     kvm list <kvm@vger.kernel.org>
Subject: Re: What's with all of the hardcoded instruction lengths in svm.c?
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References: <CALMp9eQ4k71ox=0xQKM+CfOkFe6Vqp+0znJ3Ju4ZmyL9fgjm=w@mail.gmail.com> <87d0jhegjj.fsf@vitty.brq.redhat.com> <CALMp9eTe_iSgn5ihod_B=H1JzXwc_=CW22u+5sQCyPT=EJuLPQ@mail.gmail.com>
Date:   Fri, 14 Jun 2019 19:01:48 +0200
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Jim Mattson <jmattson@google.com> writes:

> On Thu, Jun 13, 2019 at 6:55 AM Vitaly Kuznetsov <vkuznets@redhat.com> wrote:
>
>> I can try sending a patch removing the manual advancement to see if
>> anyone has any objections.
>
> That would be great!
>

Turns out this is harder than I initially thought, in the emulator we
don't emulate everything (e.g. XSETVB) and emulating some instructions
(even with EMULTYPE_SKIP) gives us some unintended side-effects,
e.g. I'm currently observing a hang when trying to apply
kvm_emulate_instruction() to HLT.  

Overall, I still think this is the right approach, we just need to make
EMULTYPE_SKIP skip correctly. Stay tuned...

-- 
Vitaly