From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AF3EF33DC; Mon, 19 Jun 2023 12:42:02 +0000 (UTC) Received: from out30-113.freemail.mail.aliyun.com (out30-113.freemail.mail.aliyun.com [115.124.30.113]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E2B1F91; Mon, 19 Jun 2023 05:41:59 -0700 (PDT) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R191e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045168;MF=hengqi@linux.alibaba.com;NM=1;PH=DS;RN=13;SR=0;TI=SMTPD_---0VlXETWq_1687178514; Received: from localhost(mailfrom:hengqi@linux.alibaba.com fp:SMTPD_---0VlXETWq_1687178514) by smtp.aliyun-inc.com; Mon, 19 Jun 2023 20:41:55 +0800 Date: Mon, 19 Jun 2023 20:41:54 +0800 From: Heng Qi To: "Michael S. Tsirkin" Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Jason Wang , Xuan Zhuo , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend Subject: Re: [PATCH net-next 4/4] virtio-net: remove F_GUEST_CSUM check for XDP loading Message-ID: <20230619124154.GC74977@h68b04307.sqa.eu95> References: <20230619105738.117733-1-hengqi@linux.alibaba.com> <20230619105738.117733-5-hengqi@linux.alibaba.com> <20230619071347-mutt-send-email-mst@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230619071347-mutt-send-email-mst@kernel.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-Spam-Status: No, score=-9.9 required=5.0 tests=BAYES_00, ENV_AND_HDR_SPF_MATCH,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE,UNPARSEABLE_RELAY,USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Mon, Jun 19, 2023 at 07:16:20AM -0400, Michael S. Tsirkin wrote: > On Mon, Jun 19, 2023 at 06:57:38PM +0800, Heng Qi wrote: > > Lay the foundation for the subsequent patch > > which subsequent patch? this is the last one in series. > > > to complete the coexistence > > of XDP and virtio-net guest csum. > > > > Signed-off-by: Heng Qi > > Reviewed-by: Xuan Zhuo > > --- > > drivers/net/virtio_net.c | 4 +--- > > 1 file changed, 1 insertion(+), 3 deletions(-) > > > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > > index 25b486ab74db..79471de64b56 100644 > > --- a/drivers/net/virtio_net.c > > +++ b/drivers/net/virtio_net.c > > @@ -60,7 +60,6 @@ static const unsigned long guest_offloads[] = { > > VIRTIO_NET_F_GUEST_TSO6, > > VIRTIO_NET_F_GUEST_ECN, > > VIRTIO_NET_F_GUEST_UFO, > > - VIRTIO_NET_F_GUEST_CSUM, > > VIRTIO_NET_F_GUEST_USO4, > > VIRTIO_NET_F_GUEST_USO6, > > VIRTIO_NET_F_GUEST_HDRLEN > > What is this doing? Drop support for VIRTIO_NET_F_GUEST_CSUM? Why? guest_offloads[] is used by the VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET command to switch features when XDP is loaded/unloaded. If the VIRTIO_NET_F_CTRL_GUEST_OFFLOADS feature is negotiated: 1. When XDP is loaded, virtnet_xdp_set() uses virtnet_clear_guest_offloads() to automatically turn off the features in guest_offloads[]. 2. when XDP is unloaded, virtnet_xdp_set() uses virtnet_restore_guest_offloads() to automatically restore the features in guest_offloads[]. Now, this work no longer makes XDP and _F_GUEST_CSUM mutually exclusive, so this patch removed the _F_GUEST_CSUM from guest_offloads[]. > This will disable all of guest offloads I think .. No. This doesn't change the dependencies of other features on _F_GUEST_CSUM. Removing _F_GUEST_CSUM here does not mean that other features that depend on it will be turned off at the same time, such as _F_GUEST_TSO{4,6}, F_GUEST_USO{4,6}, etc. Thanks. > > > > @@ -3522,10 +3521,9 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, > > virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) || > > virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) || > > virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO) || > > - virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM) || > > virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO4) || > > virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_USO6))) { > > - NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing GRO_HW/CSUM, disable GRO_HW/CSUM first"); > > + NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing GRO_HW, disable GRO_HW first"); > > return -EOPNOTSUPP; > > } > > > > -- > > 2.19.1.6.gb485710b