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Subject: Re: 1M hugepage size being registered on Linux
From: Benjamin Herrenschmidt <benh@au1.ibm.com>
Reply-To: benh@au1.ibm.com
To: Michael Ellerman <mpe@ellerman.id.au>, victora
 <victora@linux.vnet.ibm.com>, alistair@popple.id.au, jk@ozlabs.org
Cc: victora@br.ibm.com, mauricfo@linux.vnet.ibm.com, linuxppc-dev@ozlabs.org
Date: Thu, 22 Jun 2017 03:09:31 -0500
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References: <322aa4a1a11ca79008a8c894c12a80d5@linux.vnet.ibm.com>
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On Thu, 2017-06-22 at 13:59 +1000, Michael Ellerman wrote:
> It's unsupported in Linux because it doesn't match the page table
> geometry.
> 
> We merged a patch from Aneesh to filter it out in 4.12-rc1:
> 
>   a525108cf1cc ("powerpc/mm/hugetlb: Filter out hugepage size not supported by page table layout")
> 
> I guess we should probably send that patch to stable et. al.

It's also not supported in HW afaik, why is it there ?

Cheers,
Ben.