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Subject: Re: [HMM v14 05/16] mm/ZONE_DEVICE/unaddressable: add support for
 un-addressable device memory
To: =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= <jglisse@redhat.com>,
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 <1481215184-18551-6-git-send-email-jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Ross Zwisler <ross.zwisler@linux.intel.com>
From: Dave Hansen <dave.hansen@intel.com>
Message-ID: <be2861b4-d830-fbd7-e9eb-ebc8e4d913a2@intel.com>
Date: Thu, 8 Dec 2016 08:21:28 -0800
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On 12/08/2016 08:39 AM, Jérôme Glisse wrote:
> Architecture that wish to support un-addressable device memory should make
> sure to never populate the kernel linar mapping for the physical range.

Does the platform somehow provide a range of physical addresses for this
unaddressable area?  How do we know no memory will be hot-added in a
range we're using for unaddressable device memory, for instance?