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Subject: RE: [PATCH -V10 10/15] powerpc: Prevent gcc to re-read the pagetables
Date: Wed, 5 Jun 2013 16:41:45 +0100
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From: "David Laight" <David.Laight@ACULAB.COM>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>,
 <benh@kernel.crashing.org>, <paulus@samba.org>
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>  	ptep =3D pte_offset_kernel(&pmd, addr);
>  	do {
> -		pte_t pte =3D *ptep;
> +		pte_t pte =3D ACCESS_ONCE(*ptep);

Why not just define ptep as a 'pointer to volatile'?

	David