From patchwork Tue Oct 25 20:12:12 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aaron Conole X-Patchwork-Id: 686696 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3t3PTJ1fNKz9t1L for ; Wed, 26 Oct 2016 07:12:36 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932804AbcJYUMP (ORCPT ); Tue, 25 Oct 2016 16:12:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33476 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756079AbcJYUMO (ORCPT ); Tue, 25 Oct 2016 16:12:14 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1ED82C05A285; Tue, 25 Oct 2016 20:12:14 +0000 (UTC) Received: from dhcp-25-97.bos.redhat.com (dhcp-25-172.bos.redhat.com [10.18.25.172]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u9PKCDdR006676; Tue, 25 Oct 2016 16:12:13 -0400 From: Aaron Conole To: netdev@vger.kernel.org Cc: virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, "Michael S. Tsirkin" , Jarod Wilson Subject: [PATCH v2 net-next] virtio-net: Update the mtu code to match virtio spec Date: Tue, 25 Oct 2016 16:12:12 -0400 Message-Id: <1477426332-31093-1-git-send-email-aconole@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Tue, 25 Oct 2016 20:12:14 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The virtio committee recently ratified a change, VIRTIO-152, which defines the mtu field to be 'max' MTU, not simply desired MTU. This commit brings the virtio-net device in compliance with VIRTIO-152. Additionally, drop the max_mtu branch - it cannot be taken since the u16 returned by virtio_cread16 will never exceed the initial value of max_mtu. Signed-off-by: Aaron Conole Acked-by: "Michael S. Tsirkin" Acked-by: Jarod Wilson --- Nothing code-wise has changed, but I've included the ACKs and fixed up the subject line. drivers/net/virtio_net.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 720809f..2cafd12 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1870,10 +1870,12 @@ static int virtnet_probe(struct virtio_device *vdev) mtu = virtio_cread16(vdev, offsetof(struct virtio_net_config, mtu)); - if (mtu < dev->min_mtu || mtu > dev->max_mtu) + if (mtu < dev->min_mtu) { __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU); - else + } else { dev->mtu = mtu; + dev->max_mtu = mtu; + } } if (vi->any_header_sg)