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Date: Wed, 18 Nov 2009 16:21:34 +0200
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] Stack corruption problem with SeaBIOS/gPXE under QEMU
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To: Gleb Natapov <gleb@redhat.com>
Cc: qemu-devel@nongnu.org, Glauber Costa <glommer@redhat.com>, Kevin O'Connor <kevin@koconnor.net>, gpxe@etherboot.org, Naphtali Sprei <nsprei@redhat.com>

On 11/18/2009 04:19 PM, Gleb Natapov wrote:
>>>
>>> Do we have the same problem with tpr patching rom (vapic,bin)? It modifies
>>> itself too.
>>>        
>> But a reset will reload it.
>>
>>      
> Correct, but Kevin says "sendkey ctrl-alt-delete" jumps to SeaBIOS's
> reboot vector without issuing system reset. I am talking about this situation.
>    

That's only if we're in the bios.  If an OS has taken over, it will 
issue a proper reset.  If an OS has not taken over (DOS won't, probably) 
then it isn't Windows and the vapic payload hasn't had a chance to 
modify itself.

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