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From: Kumar Gala <kumar.gala@freescale.com>
Date: Wed, 6 Apr 2005 12:58:53 -0500
To: "Chris Friesen" <cfriesen@nortel.com>
Cc: linux-ppc-embedded list <linuxppc-embedded@ozlabs.org>,
	Paul Mackerras <paulus@samba.org>,
	linuxppc-dev list <linuxppc-dev@ozlabs.org>
Subject: Re: pte_update and 64-bit PTEs on PPC32?
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On Apr 6, 2005, at 12:20 PM, Chris Friesen wrote:

> Kumar Gala wrote:
>
> > static inline pte_t ptep_get_and_clear(struct mm_struct *mm, =
unsigned
>  > long addr,
>  >=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=
=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 pte_t *ptep)
>  > {
>  >=A0=A0=A0=A0=A0=A0=A0=A0 pte_t tmp =3D *ptep;
>  >=A0=A0=A0=A0=A0=A0=A0=A0 pte_update(ptep, ~_PAGE_HASHPTE, 0);
>  >=A0=A0=A0=A0=A0=A0=A0=A0 return tmp;
>  > }
>
> Doesn't work.=A0 The update and storing of the old value must be =
atomic.
> The value of the pte can change between storing the tmp value and
> calling pte_update().

Thanks, realized this after a bit more thought, and some discussion on=20=

lkml :)

Guess, I need to write a 64-bit pte version of pte_update, foo!

- kumar