minidump size on amd64

[Alan Cox]

Andriy Gapon wrote:
> on 03/11/2010 20:44 Alan Cox said the following:
> [snip]
>
> Thank you for the confirmation!
>
>   
>> Andriy Gapon wrote:
>>     
>>> P.S. is there a macro for extracting frame address from PDPE?
>>>       
>> To a lower level page table page or to a 1GB physical page?  For the latter, you
>> can use PG_PS_FRAME.
>>     
>
> To a 1GB page.
> I see in the architecture manual that the lower bits are marked as MBZ, so this
> macro should work.  Actually, it seems that even PG_FRAME should work in place of
> PG_PS_FRAME for exactly the same reason (MBZ) on amd64.
>   

There is actually a point to using PG_PS_FRAME.  The PAT bit for a 2MB 
page mapping occupies a bit that is a part of the physical page number 
with PG_FRAME.  I suspect that the same is true of 1GB page mappings, 
but I haven't double checked the manual.

Alan