From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39564) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f1C0K-0004Xk-MA for qemu-devel@nongnu.org; Wed, 28 Mar 2018 10:24:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f1C0H-000338-FL for qemu-devel@nongnu.org; Wed, 28 Mar 2018 10:24:44 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:51770 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1f1C0H-00032q-Ad for qemu-devel@nongnu.org; Wed, 28 Mar 2018 10:24:41 -0400 Date: Wed, 28 Mar 2018 17:24:33 +0300 From: "Michael S. Tsirkin" Message-ID: <20180328172057-mutt-send-email-mst@kernel.org> References: <1516308132-10272-1-git-send-email-mst@redhat.com> <1516308132-10272-3-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PULL v4 02/29] vhost-user: add new vhost user messages to support virtio config space List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Maxime Coquelin Cc: qemu-devel@nongnu.org, Changpeng Liu , Peter Maydell , =?iso-8859-1?Q?Marc-Andr=E9?= Lureau On Wed, Mar 28, 2018 at 12:03:36PM +0200, Maxime Coquelin wrote: > Hi, >=20 > On 01/18/2018 09:44 PM, Michael S. Tsirkin wrote: > > From: Changpeng Liu > >=20 > > Add VHOST_USER_GET_CONFIG/VHOST_USER_SET_CONFIG messages which can be > > used for live migration of vhost user devices, also vhost user device= s > > can benefit from the messages to get/set virtio config space from/to = the > > I/O target. For the purpose to support virtio config space change, > > VHOST_USER_SLAVE_CONFIG_CHANGE_MSG message is added as the event noti= fier > > in case virtio config space change in the slave I/O target. > >=20 > > Signed-off-by: Changpeng Liu > > Reviewed-by: Marc-Andr=E9 Lureau > > Reviewed-by: Michael S. Tsirkin > > Signed-off-by: Michael S. Tsirkin > > --- > > docs/interop/vhost-user.txt | 55 ++++++++++++++++++ > > include/hw/virtio/vhost-backend.h | 12 ++++ > > include/hw/virtio/vhost.h | 15 +++++ > > hw/virtio/vhost-user.c | 118 +++++++++++++++++++++++++++= +++++++++++ > > hw/virtio/vhost.c | 32 +++++++++++ > > 5 files changed, 232 insertions(+) > >=20 >=20 > As discussed with Changpeng on DPDK ML, we need a vhost-user protocol > feature bit to back these new requests, else QEMU cannot whether the > user backend implement these. >=20 > With current and older DPDK version, if an unknown request is received, > the socket connection is closed. >=20 > Do we still have time before QEMU v2.12 is out? >=20 > Thanks, > Maxime We certainly do, and I agree it's a concern as we get maintain protocol extensions forever. It's my bad that I forgot to check that there's a feature bit, but I think we should act before the release. There is probably time enough to add it - but if no one can spare then time it would be better to disable the new messages in QEMU for now than ship 2.12 without a feature bit. I wonder what's Changpeng Liu's take on this. --=20 MST