Re: [PATCH v2 0/2] kvm "fake DAX" device

[Dan Williams]

On Fri, Oct 12, 2018 at 10:00 PM Pankaj Gupta <pagupta@xxxxxxxxxx> wrote:
>
>  This patch series has implementation for "fake DAX".
>  "fake DAX" is fake persistent memory(nvdimm) in guest
>  which allows to bypass the guest page cache. This also
>  implements a VIRTIO based asynchronous flush mechanism.

Can we stop calling this 'fake DAX', because it isn't 'DAX' and it's
starting to confuse people. This enabling is effectively a
host-page-cache-passthrough mechanism not DAX. Let's call the whole
approach virtio-pmem, and leave DAX out of the name to hopefully
prevent people from wondering why some DAX features are disabled with
this driver. For example MAP_SYNC is not compatible with this
approach.

Additional enabling is need to disable MAP_SYNC in the presence of a
virtio-pmem device. See the rough proposal here:

    https://lkml.org/lkml/2018/4/25/756