Re: [PATCH 0 of 4] x86: some more patches

Andi Kleen
2008-01-16T14:44:28Z

> Index: linux-x86.q/include/asm-x86/page.h
> ===================================================================
> --- linux-x86.q.orig/include/asm-x86/page.h
> +++ linux-x86.q/include/asm-x86/page.h
> @@ -11,7 +11,7 @@
> #ifdef __KERNEL__
>
> #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.

> -#define PTE_MASK PHYSICAL_PAGE_MASK
> +#define PTE_MASK (_AT(long, PHYSICAL_PAGE_MASK))

That would mean it is 32bit again because 32bit long is 32bit, but on 32bit
PAE PTE_MASK definitely needs to be 64bit.

So I would be surprised if the patch works.

The problem seems to be rather that PAGE_MASK does not include the bits above 32bit.
Something like

#define PHYSICAL_PAGE_MASK (__PHYSICAL_MASK & ~(phys_addr_t)(PAGE_SIZE-1))

should work (untested)

-Andi