On Tue, 2002-07-16 at 10:43, Joe George wrote:
> I'll disagree with both of you so I may learn from the flames. :-)
> First it's true the patch wasn't formatted for oss and should have
> been rejected on that basis. At least my patches would be. :)
Well, my agreement with Ralf was that the patch wasn't formatted for the
oss tree, not that it's not applicable.
> But Vivien Chappelier said it fixed his X server problem in mips64.
> CONFIG_64BIT_PHYS_ADDR is applicable to both 36 and 64
> bit code, I think.
>
> So the crux of my question is, if an unsigned long long pte is
> and'ed with an unsigned long PAGE_CHG_MASK what happens
> to the upper 32 bits of pte. On a 64 bit processor is PAGE_CHG_MASK
> sign extended so everything is fine, or does it zero the upper
> 32 bits?
I think the upper 32 bits get zeroed out. The fact that it fixed Vivien's
problem confirms this (he was running oss, right?)
Pete
> Joe
>
>
> Pete Popov wrote:
> > On Tue, 2002-07-16 at 08:07, Ralf Baechle wrote:
> >
> >>On Mon, Jul 15, 2002 at 03:29:10PM -0700, Pete Popov wrote:
> >>
> >>
> >>>--- include/asm-mips/pgtable.h.old Fri Jul 12 17:25:19 2002
> >>>+++ include/asm-mips/pgtable.h Fri Jul 12 17:25:36 2002
> >>>@@ -332,7 +332,9 @@
> >>>
> >>> static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
> >>> {
> >>>- return __pte(((pte).pte_low & _PAGE_CHG_MASK) | pgprot_val(newprot));
> >>>+ pte.pte_low &= _PAGE_CHG_MASK;
> >>>+ pte.pte_low |= pgprot_val(newprot);
> >>>+ return pte;
> >>> }
> >>>
> >>This patch certainly doesn't apply to oss. Seems somebody did copy all
> >>the x86 pte_t and stuff into your tree without too much thinking ...
> >>
> >
> > That's right, I forgot you don't have the 36 bit code that uses pte_low
> > and pte_high.
> >
> > Pete
> >
>
>
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