Re: [PATCH 0 of 4] x86: some more patches
From: Ingo Molnar
Date: Wed Jan 16 2008 - 09:54:55 EST
* Andi Kleen <ak@xxxxxxx> wrote:
> > #define PHYSICAL_PAGE_MASK (PAGE_MASK & __PHYSICAL_MASK)
>
>
> I haven't tested yet, but we looked at that one earlier and I thought
> it was ok because
>
> #define __PHYSICAL_MASK _AT(phys_addr_t, (_AC(1,ULL) << __PHYSICAL_MASK_SHIFT) - 1)
>
> and
>
> typedef u64 phys_addr_t;
>
> for PAE. So the expression above should have been already 64bit.
no. The problem is that PAGE_MASK is:
#define PAGE_MASK (~(PAGE_SIZE-1))
#define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT)
that's u32 on PAE, and __PHYSICAL_MASK is u64. So PAGE_MASK gets
zero-extended to u64. So the combined mask:
#define PHYSICAL_PAGE_MASK (PAGE_MASK & __PHYSICAL_MASK)
has the high bits chopped off. Please try my patch.
(PHYSICAL_PAGE_MASK is broken too in the same way, i just fixed that in
my tree - but it's not used by anything on 32-bit PAE but by PAGE_MASK)
> So I would be surprised if the patch works.
try it ...
Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/