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Message-ID: <1360701185.2035.10.camel@pasglop>
Subject: Re: [PATCH 2/2] powerpc: Make context bits depend on virtual addr
 size.
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Date: Wed, 13 Feb 2013 07:33:05 +1100
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On Wed, 2013-02-13 at 00:01 +0530, Aneesh Kumar K.V wrote:
> + * Be careful with this value. This determines the VSID_MODULUS_*  and that
> + * need to be co-prime with VSID_MULTIPLIER*
> + */
> +#if defined(CONFIG_POWER6_CPU) || defined(CONFIG_POWER7_CPU)
> +/*
> + * Even if cpu support 68 bits, we limit this to 66 because
> + * we support only 2^19 context.
> + */
> +#define MAX_VIRTUAL_ADDR_BITS 66
> +#else
> +/* power4,power 5 and cell is 65 */
> +#define MAX_VIRTUAL_ADDR_BITS 65
> +#endif
> +

A compile option ? Really ? Ugh...

Ben.