From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by dpdk.org (Postfix) with ESMTP id 6A35237B2 for ; Mon, 14 Dec 2015 14:38:43 +0100 (CET) Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga103.fm.intel.com with ESMTP; 14 Dec 2015 05:38:42 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,427,1444719600"; d="scan'208";a="12832391" Received: from fmsmsx104.amr.corp.intel.com ([10.18.124.202]) by fmsmga004.fm.intel.com with ESMTP; 14 Dec 2015 05:38:42 -0800 Received: from fmsmsx119.amr.corp.intel.com (10.18.124.207) by fmsmsx104.amr.corp.intel.com (10.18.124.202) with Microsoft SMTP Server (TLS) id 14.3.248.2; Mon, 14 Dec 2015 05:38:42 -0800 Received: from shsmsx102.ccr.corp.intel.com (10.239.4.154) by FMSMSX119.amr.corp.intel.com (10.18.124.207) with Microsoft SMTP Server (TLS) id 14.3.248.2; Mon, 14 Dec 2015 05:38:41 -0800 Received: from shsmsx101.ccr.corp.intel.com ([169.254.1.190]) by shsmsx102.ccr.corp.intel.com ([169.254.2.158]) with mapi id 14.03.0248.002; Mon, 14 Dec 2015 21:38:40 +0800 From: "Xie, Huawei" To: Yuanhan Liu , Thomas Monjalon Thread-Topic: [dpdk-dev] [PATCH] virtio: fix virtio_net_hdr desc pointing to the same buffer Thread-Index: AQHRNnDCXtURtGAUZESyzyv2F/Vglp7KdNpA Date: Mon, 14 Dec 2015 13:38:39 +0000 Message-ID: References: <1449763652-86292-1-git-send-email-huawei.xie@intel.com> <1485514.3e9eA57k0j@xps13> <20151214114732.GB29571@yliu-dev.sh.intel.com> <2070148.TLndilS6eD@xps13> <20151214130931.GD29571@yliu-dev.sh.intel.com> In-Reply-To: <20151214130931.GD29571@yliu-dev.sh.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Cc: "dev@dpdk.org" Subject: Re: [dpdk-dev] [PATCH] virtio: fix virtio_net_hdr desc pointing to the same buffer X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 14 Dec 2015 13:38:43 -0000 > -----Original Message----- > From: Yuanhan Liu [mailto:yuanhan.liu@linux.intel.com] > Sent: Monday, December 14, 2015 9:10 PM > To: Thomas Monjalon > Cc: Xie, Huawei; dev@dpdk.org > Subject: Re: [dpdk-dev] [PATCH] virtio: fix virtio_net_hdr desc pointing = to > the same buffer >=20 > On Mon, Dec 14, 2015 at 01:44:54PM +0100, Thomas Monjalon wrote: > > 2015-12-14 19:47, Yuanhan Liu: > > > On Mon, Dec 14, 2015 at 10:32:24AM +0100, Thomas Monjalon wrote: > > > > 2015-12-14 11:01, Yuanhan Liu: > > > > > On Fri, Dec 11, 2015 at 12:07:32AM +0800, Huawei@dpdk.org wrote: > > > > > > The virtio_net_hdr desc all pointed to the same buffer. It > doesn't cause > > > > > > issue because in the simple TX mode we don't use the header. Th= is > patch > > > > > > makes the header desc point to different buffer. > > > > > > > > > > > > Signed-off-by: Huawei Xie > > > > > > > > > > Acked-by: Yuanhan Liu > > > > > > > > Does it fix something in the current behaviour? > > > > > > It's more like a logic fixing to me. > > > > > > > I have the feeling it may wait for 2.3. > > > > > > It's been introduced in v2.2, with Huawei's simple tx patchset. > > > Therefore, I guess 2.2 is good to go? > > > > The vhost driver has been validated without with patch. >=20 > Huawei stated in the commit log that "It doesn't cause issue because in > the simple TX mode we don't use the header". >=20 > > Merging it would be taking the risk of breaking something > > (or just reduce performance) for no clear benefit. > > Am I missing something? >=20 Thomas, there is no risk at all with this patch, and it will not affect per= formance. I prefer to integrate this patch, so that we have a good looking vhost libr= ary. :). > I know your concerns: we really should be cagy about making any changes > when a release is close, especially when all stuff are validated. From > this point of view, I agree with you we could delay it to v2.3. >=20 > Maybe huawei have more inputs here? >=20 > --yliu