[PATCH V2 10/11] powerpc/mm/radix: Make max pfn bits a variable

[Paul Mackerras]

On Thu, Mar 16, 2017 at 04:02:08PM +0530, Aneesh Kumar K.V wrote:
> This makes max pysical address bits a variable so that hash and radix
> translation mode can choose what value to use. In this patch we also switch the
> radix translation mode to use 57 bits. This make it resilient to future changes
> to max pfn supported by platforms.
> 
> This patch is split from the previous one to make the review easier.
> 
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>

Why do we need to do this now?  It seems like this will add overhead
every time we set a PTE for no current benefit.

Paul.