Thank you Mulyadi,

On 7/10/08, Mulyadi Santosa <[EMAIL PROTECTED]> wrote:
>  >
>  > If default mapping (via cr3/pgd mechanism) is ZONE_NORMAL, then how do
>  > we allocate memory in the ZONE_HIGHMEM region?   (ie, does
>  > __get_free_pages() or alloc_pages() return us anything in those
>  > region?)
>  >
>
> Don't get confused, alloc_pages() has no problem "touching" highmem
>  pages. The problem is, when you need to address those pages (I am sure
>  you realize this issue too), you need to map them into kernel address
>  space. That's where kmap() or kmap_atomic() comes into rescue.
>

Ok, to summarize:

1.   __get_free_pages(GFP_HIGHMEM, order)---> it will be from ZONE_HIGHMEM

2.   Or alloc_pages(GFP_HIGHMEM, order).

3.   After these just kmap() them to get the virtual address, right?

Thank you very much.

-- 
Regards,
Peter Teoh

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