[SeaBIOS] [PATCH] vcpu hotplug: Setup vcpu add/remove infrastructure

[Liu, Jinsong]

Gleb Natapov wrote:
> On Sat, Jan 30, 2010 at 12:52:54AM +0800, Liu, Jinsong wrote:
>> Gleb Natapov wrote:
>>> On Fri, Jan 29, 2010 at 11:34:24PM +0800, Liu, Jinsong wrote:
>>>> Gleb Natapov wrote:
>>>>> On Thu, Jan 28, 2010 at 10:54:48PM +0800, Liu, Jinsong wrote:
>>>>>> Connor and Gleb,
>>>>>> 
>>>>>> I updated my patch according to our discussion:
>>>>>> 1. simplify scan loop according to 'maxvcpus';
>>>>>> 2. remove unecessary global variables;
>>>>>> 3. change hardcode address to bios use only area '0x514';
>>>>>> 4. remove simple \_PR scope from ssdt;
>>>>>> 
>>>>> I still don't see that ACPI NVS issue is addressed.
>>>> 
>>>> Gleb,
>>>> 
>>>> I'm not quite sure Win7 BSOD issue you mentioned last email, anyway
>>>> I update my patch, define ACPI NVS per my understanding.
>>> You need checked build of Windows 7. This is not regular Win7 this
>>> is debug version that you can download from MSDN. Here is the bug
>>> report about the crash:
>>> http://sourceforge.net/tracker/?func=detail&aid=2902983&group_id=180599&atid=893831
>>> 
>>> Anyway according to ACPI spec ACPI DATA area can be reused by an OS
>>> after reading ACPI tables so it is wrong to access this memory
>>> after an OS boot. 
>>> 
>> 
>> Yes, it's safer to define ACPI NVS, although it's bios use only area.
>> 
> APCI DATA is explicitly not defined by ACPI spec as "bios use only
> area".

Yes, it's not defined by ACPI spec, but from default x86 memory layout, refer to Documentation/x86/boot.txt:
001000  +------------------------+
        |  Reserved for MBR/BIOS |
000800  +------------------------+
        |  Typically used by MBR |
000600  +------------------------+
        |  BIOS use only         |
000000  +------------------------+


Thanks,
Jinsong