Re: bisected boot regression post 2.6.25-rc3.. please revert

From: Ingo Molnar
Date: Sun Mar 09 2008 - 14:58:53 EST



* Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:

> So I would *very* strongly instead argue:
>
> - "unsigned long" is the native kernel type for all address manipulation,
> and thus "PAGE_SIZE" and "PAGE_MASK" should continue to have that type.
>
> - anything that uses any other type without explicitly making sure it's
> safe is mis-using those macros. IOW, PAGE_MASk was *never* a type that
> had anything what-so-ever to do with page table entry bits, and this is
> purely a page table entry issue!
>
> So my suggested patch would:
>
> - make the page table code use a specific mask that it builds up itself,
> and makes sure it's of the right type and has the rigth value in
> whatever type "struct pte_entry" is. The fact that "pte_val()" is
> larger than "unsigned long" on x86-32 is very clearly a PTE issue,
> *not* an issue for PAGE_SIZE or PAGE_MASK.

yeah, indeed my patch was sloppy, i didnt think it through - i fell for
the lure of the easy-looking 'PAGE_SIZE is small, sign-extend it' hack.

Will do it cleanly and will also clean up all the pte/address/pgprot
type mixing that currently goes on in this maze of macros.

Ingo
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