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Date: Thu, 19 Oct 2017 01:01:49 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Dan Williams <dan.j.williams@intel.com>
Cc: Stefan Hajnoczi <stefanha@gmail.com>,
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Subject: Re: [Qemu-devel] [RFC 2/2] KVM: add virtio-pmem driver
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On Wed, Oct 18, 2017 at 08:51:37AM -0700, Dan Williams wrote:
> This use case is not "Persistent Memory". Persistent Memory is
> something you can map and make persistent with CPU instructions.
> Anything that requires a driver call is device driver managed "Shared
> Memory".

How is this any different than the existing nvdimm_flush()? If you
really care about the not driver thing it could easily be a write
to a doorbell page or a hypercall, but in the end that's just semantics.