From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37235) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gMage-0007nC-20 for qemu-devel@nongnu.org; Tue, 13 Nov 2018 10:33:09 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gMagZ-0001Ls-RD for qemu-devel@nongnu.org; Tue, 13 Nov 2018 10:33:08 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47034) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gMagZ-0001Ku-Gp for qemu-devel@nongnu.org; Tue, 13 Nov 2018 10:33:03 -0500 Date: Tue, 13 Nov 2018 10:32:59 -0500 From: "Michael S. Tsirkin" Message-ID: <20181113103232-mutt-send-email-mst@kernel.org> References: <20181109145827.23076-1-yuri.benditovich@daynix.com> <20181109125947-mutt-send-email-mst@kernel.org> <20181111215232-mutt-send-email-mst@kernel.org> <20181112155208-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH] virtio-net: support RSC v4/v6 tcp traffic for Windows HCK List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Yuri Benditovich Cc: Jason Wang , Dmitry Fleytman , qemu-devel@nongnu.org, Yan Vugenfirer On Tue, Nov 13, 2018 at 10:21:07AM +0200, Yuri Benditovich wrote: >=20 >=20 > On Mon, Nov 12, 2018 at 10:53 PM Michael S. Tsirkin wr= ote: >=20 > On Mon, Nov 12, 2018 at 01:31:36PM +0200, Yuri Benditovich wrote: > > > > > > On Mon, Nov 12, 2018 at 11:26 AM Jason Wang = wrote: > > > > > >=C2=A0 =C2=A0 =C2=A0On 2018/11/12 =E4=B8=8B=E5=8D=884:57, Yuri Ben= ditovich wrote: > >=C2=A0 =C2=A0 =C2=A0> > >=C2=A0 =C2=A0 =C2=A0> On Mon, Nov 12, 2018 at 4:54 AM Michael S. T= sirkin >=C2=A0 =C2=A0 =C2=A0> > wrote: > >=C2=A0 =C2=A0 =C2=A0> > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0On Sun, Nov 11, 2018 at 1= 2:18:54PM +0200, Yuri Benditovich > wrote: > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0> @@= -66,12 +143,16 @@ typedef struct VirtIONet { > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0>=C2= =A0 =C2=A0 =C2=A0 VirtIONetQueue *vqs; > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0>=C2= =A0 =C2=A0 =C2=A0 VirtQueue *ctrl_vq; > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0>=C2= =A0 =C2=A0 =C2=A0 NICState *nic; > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0> +=C2= =A0 =C2=A0 QTAILQ_HEAD(, NetRscChain) rsc_chains; > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0> > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0what= exactly happens with these chains on migration? > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0> > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0> > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0> This feature (software = implementation of RSC in QEMU) is > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0intended to be used in > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0> the environment of cert= ification tests which never uses > migration. > >=C2=A0 =C2=A0 =C2=A0> > >=C2=A0 =C2=A0 =C2=A0>=C2=A0 =C2=A0 =C2=A0Should this feature disab= le migration then? > >=C2=A0 =C2=A0 =C2=A0> > >=C2=A0 =C2=A0 =C2=A0> > >=C2=A0 =C2=A0 =C2=A0> IMO, this should not. But if you find it man= datory, please respond > and > >=C2=A0 =C2=A0 =C2=A0> I will add the migration blocker. > > > > > >=C2=A0 =C2=A0 =C2=A0So if my understanding is correct, it's safe t= o do nothing even if we > >=C2=A0 =C2=A0 =C2=A0allow migration for RSC? > > > > > > This does not create any unrecoverable failure (assertion, BSOD), > although > > some data (coalesced parts of packets not delivered yet to guest)= will be > lost. >=20 > If guest has no way to detect none of these packets were ever > received by card, then I guess it's fine. Needs a > comment in case we start caring about packet loss around > migration. >=20 >=20 >=20 > Where is the best place to place such a comment in the code? Maybe where we add the fields that we don't bother migrating. > Are there more notes toward v3 of the patch? >=20 Not yet. >=20 > > > > > >=C2=A0 =C2=A0 =C2=A0Thanks > > > > > > >=20