[parisc-linux] MAX_ADDRESS.

[James Bottomley]

On Tue, 2003-09-30 at 07:24, Naresh wrote:
> MAX_ADDRESS has nothing to do with DISCONTIGMEM. Its definition is generic(
> pgtable.h), although it is not used anywhere. I just happened to see the comment in
> the DISCONTIGMEM code. Even if DISCONTIGMEM is turned off, there is no check for
> MAX_ADDRESS before the call to 'map_pages()' in 'pagetable_init( )', which is why I
> would like to know if MAX_ADDRESS can be ignored.

No.  It does represent the highest virtual address possible.

Linux has 3 levels of page tables, so on a 64 bit kernel (8 bytes per
pte and 8 bytes per pte page pointer etc), we can address a maximum of
512GB with 4k pages.

James