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Date: Fri, 06 May 2016 10:43:37 +0530
From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
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To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>,
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CC: mikey@neuling.org, oohall@gmail.com
Subject: Re: [PATCH 0/2] Enable ZONE_DEVICE on POWER
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On 05/05/2016 08:18 PM, Aneesh Kumar K.V wrote:
> Anshuman Khandual <khandual@linux.vnet.ibm.com> writes:
> 
>> This enables base ZONE_DEVICE support on POWER. This series depends on
>> the following patches posted by Oliver.
>>
>> https://patchwork.ozlabs.org/patch/618867/
>> https://patchwork.ozlabs.org/patch/618868/
>>
>> Anshuman Khandual (2):
>>   powerpc/mm: Make vmemmap_populate accommodate ZONE_DEVICE memory
>>   powerpc/mm: Enable support for ZONE_DEVICE on PPC_BOOK3S_64 platforms
>>
>>  arch/powerpc/mm/init_64.c | 4 +++-
>>  mm/Kconfig                | 2 +-
>>  2 files changed, 4 insertions(+), 2 deletions(-)
>>
> 
> What is the use case ? Who will use ZONE_DEVICE on ppc64. This should be
> be merged along with the patch series that use this. 

IIUC, Oliver has been looking at using ZONE_DEVICE for the NVDIMM (or
some other persistent memory) drivers. I have been following Dan William's
work on this front and want to explore more details about it's functioning
on ppc64. This enablement will just help us little bit in that direction.