Re: [RFT] kvm with Windows optimization

Avi Kivity
2007-10-30T04:03:08Z

Anthony Liguori wrote:
> Dong, Eddie wrote:
>> Anthony Liguori wrote:
>>
>>> Dong, Eddie wrote:
>>>
>>>>> BTW, is it wise to enable this by default for all guests?
>>>>> Ignoring the
>>>>> fact that we're modifying guest's memory without its knowledge, if a
>>>>> guest unmaps the VA mappings for the BIOS then all sorts of
>>>>> problems could occur.
>>>>>
>>>>>
>>>> Good movement!
>>>>
>>>> But, Vista won't work with patching. The memory guard in vista
>>>> will make the system refuse to service. Maybe we need a option to
>>>> check if it is vista.
>>>>
>>> FWIW, I successfully installed and booted Vista Enterprise Edition
>>> with the TPR optimization patch.
>>>
>>>
>> 32 bits or 64 bits?
>> See
>> http://blogs.msdn.com/windowsvistasecurity/archive/2006/08/11/695993.asp
>> x
>>
>> It says:
>>
>> There are many brand new security features in Windows Vista, but Kernel
>> Patch Protection is actually not one of them. Kernel Patch Protection
>> was first supported on x64 (AMD64 and Intel EMT64T) CPU architecture
>> versions of Microsoft Windows including Microsoft Windows Server 2003
>> SP1 and Windows XP Microsoft Windows XP Professional x64 Edition. (Patch
>> protection is currently not supported on x86 or ia64 architectures.)
>> Though, as the use of 64-bit computers is increasing, Windows Vista
>> users will end up benefiting most from this technology.
>> Seems Vista 32 is not using patchguard yet, not sure about next SP.
>> If above is true, it looks like we are OK for current stage.
>> thx,eddie
>>
>
> I tested 32-bit Vista. We'll have to try 64-bit Vista and see if it
> gets upset.
>

btw, it may have not triggered because the hack didn't recognize Vista's
memory map.

--
Any sufficiently difficult bug is indistinguishable from a feature.