Re: [PATCH V2 5/6] virtio: introduce dirty page tracking facility

["Zhu, Lingshan" <lingshan.zhu@intel.com>]

On 11/3/2023 7:35 PM, Parav Pandit wrote:
> Hi Jason,
>
> > From: Zhu Lingshan <lingshan.zhu@intel.com>
> > Sent: Friday, November 3, 2023 4:05 PM
> > This commit introduce a new virtio facility to track device dirty pages, a typical
> > use case is live migration.
> >
> > The implementation of this facility is transport specific.
> >
> > Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>
> > Signed-off-by: Jason Wang <jasowang@redhat.com>
> In my series of dirty page tracking (aka write recording), you kept insisting until Thu, that it is optional, and platform will do it.
> Why do you propose this facility now?
> Can you please explain as commit log says typical use case is "live migration"? :)
You misunderstood us.

If you remember, it is you challenge our config space proposal (v1) is 
incomplete without dirty page tracking facility.

This is to answer your challenge, as an optional backup.

We still believe dirty page tracking should be better done by platform 
facilities, like vt-d.