From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH] x86 emulator: Add 'push/pop sreg' instructions
Date: Wed, 19 Aug 2009 16:03:54 +0300
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References: <1250655104-437-1-git-send-email-m.gamal005@gmail.com>	 <4A8BB8AA.5020401@redhat.com> <52d4a3890908190552y51f0d38fnbb2919d5581fb931@mail.gmail.com>
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Cc: kvm@vger.kernel.org
To: Mohammed Gamal <m.gamal005@gmail.com>
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On 08/19/2009 03:52 PM, Mohammed Gamal wrote:
>
>>> +static void emulate_push_sreg(struct x86_emulate_ctxt *ctxt, int seg)
>>> +{
>>> +       struct decode_cache *c =&ctxt->decode;
>>> +       struct kvm_segment segment;
>>> +
>>> +       if (ctxt->mode == X86EMUL_MODE_PROT64&&    (seg != VCPU_SREG_FS ||
>>> +                                                  seg != VCPU_SREG_GS)) {
>>> +               kvm_queue_exception(ctxt->vcpu, UD_VECTOR);
>>> +               return;
>>> +       }
>>>
>>>        
>> It's better to check at the callsite, in case the opcode is ever reused for
>> a new instruction.  Or even better, add a new decode flag No64 so we can do
>> this during the decode stage.
>>      
> Good idea, but I believe it'd be better to introduce it in a separate
> patch so that we can update all instructions incompatible with long
> mode in one go. I'll move the checks to the call site for the time
> being.
>    

Sure.  Or do the No64 patch first.

-- 
error compiling committee.c: too many arguments to function