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Subject: Re: [RFC PATCH 4/7] mm/follow_page_mask: Add support for hugepage
 directory entry
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>,
 benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au
References: <1491314675-15787-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com>
 <1491314675-15787-4-git-send-email-aneesh.kumar@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Date: Fri, 7 Apr 2017 17:07:02 +0530
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On 04/04/2017 07:34 PM, Aneesh Kumar K.V wrote:
> The defaul implementation prints warning and returns NULL. We will add ppc64
> support in later patches.

The description is not sufficient. The patch makes the entire follow
page mask function aware of hugepd based implementation at PGD, PUD
and PMD level. It also provides default follow_huge_pd() function
which in absence of architecture support prints warning and returns
NULL. The commit description should contain all these details.