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Date:   Mon, 12 Aug 2019 20:20:58 +0530
From:   Bharata B Rao <bharata@linux.ibm.com>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Dan Williams <dan.j.williams@intel.com>,
        Jason Gunthorpe <jgg@mellanox.com>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org
Subject: Re: [PATCH 5/5] memremap: provide a not device managed memremap_pages
Reply-To: bharata@linux.ibm.com
References: <20190811081247.22111-1-hch@lst.de>
 <20190811081247.22111-6-hch@lst.de>
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On Sun, Aug 11, 2019 at 10:12:47AM +0200, Christoph Hellwig wrote:
> The kvmppc ultravisor code wants a device private memory pool that is
> system wide and not attached to a device.  Instead of faking up one
> provide a low-level memremap_pages for it.  Note that this function is
> not exported, and doesn't have a cleanup routine associated with it to
> discourage use from more driver like users.

The kvmppc secure pages management code will be part of kvm-hv which
can be built as module too. So it would require memremap_pages() to be
exported.

Additionally, non-dev version of the cleanup routine
devm_memremap_pages_release() or equivalent would also be requried.
With device being present, put_device() used to take care of this
cleanup.

Regards,
Bharata.