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Tsirkin" , Dave Gilbert , Juan Quintela Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=2607:f8b0:4864:20::b2f; envelope-from=stefanha@gmail.com; helo=mail-yb1-xb2f.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Wed, 8 Feb 2023 at 10:58, Hanna Czenczek wrote: > > On 08.02.23 15:32, Stefan Hajnoczi wrote: > > On Tue, 7 Feb 2023 at 07:29, Stefan Hajnoczi wrote= : > >> On Tue, 7 Feb 2023 at 04:08, Hanna Czenczek wrote: > >>> On 06.02.23 17:27, Stefan Hajnoczi wrote: > >>>> On Mon, 6 Feb 2023 at 07:36, Hanna Czenczek wrot= e: > >>>> Should we schedule a call with Jason, Michael, Juan, David, etc to > >>>> discuss further? That way there's less chance of spending weeks > >>>> working on something only to be asked to change the approach later. > >>> Sure, sounds good! I=E2=80=99ve taken a look into what state we=E2= =80=99ll need to > >>> migrate already, but I=E2=80=99ll take a more detailed look now so th= at it=E2=80=99s > >>> clear what our requirements are. > > Hi Hanna, > > The next step is getting agreement on how the vhost-user device state > > interface will work. Do you want to draft the new vhost-user protocol > > messages and put together slides for discussion with Michael, Jason, > > Juan, and David in the next KVM call? That might be the best way to > > get agreement. Doing it via email is possible too but I guess it will > > take longer. > > > > If you don't want to design the vhost-user protocol changes yourself > > then someone on this email thread can help with that. > > I=E2=80=99ll need to talk about the whole thing to Stefano and German fir= st > (we=E2=80=99re collaborating on virtio-fs migration, looking at different > aspects of it). Also, I think I=E2=80=99ll want to look into the code a = bit > first and fiddle around to get a working prototype so I get an idea of > what might be feasible at all. I wouldn=E2=80=99t want to propose someth= ing > that actually can=E2=80=99t work when I try to make it work in practice. = O:) Okay. The specifics of the virtiofs device state don't need much discussion here. Only the vhost-user protocol changes need agreement because they are generic infrastructure that will affect other vhost-user device types, vDPA, and probably core VIRTIO. So don't worry about defining what each piece of virtiofs state needs to be at this point, I guess you only need a rough idea in order to come up with the vhost-user protocol changes. Stefan