From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936065AbdCJL5e (ORCPT ); Fri, 10 Mar 2017 06:57:34 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:44707 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935723AbdCJLxm (ORCPT ); Fri, 10 Mar 2017 06:53:42 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "stephen hemminger" , "David S. Miller" , "Stephen Hemminger" Date: Fri, 10 Mar 2017 11:46:10 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 179/199] netvsc: reduce maximum GSO size In-Reply-To: X-SA-Exim-Connect-IP: 82.70.136.246 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.87-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: stephen hemminger [ Upstream commit a50af86dd49ee1851d1ccf06dd0019c05b95e297 ] Hyper-V (and Azure) support using NVGRE which requires some extra space for encapsulation headers. Because of this the largest allowed TSO packet is reduced. For older releases, hard code a fixed reduced value. For next release, there is a better solution which uses result of host offload negotiation. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller [bwh: Backported to 3.2: adjust filename, context] Signed-off-by: Ben Hutchings --- drivers/staging/hv/netvsc_drv.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/staging/hv/netvsc_drv.c +++ b/drivers/staging/hv/netvsc_drv.c @@ -52,6 +52,9 @@ struct net_device_context { /* Need this many pages to handle worst case fragmented packet */ #define PACKET_PAGES_HIWATER (MAX_SKB_FRAGS + 2) +/* Restrict GSO size to account for NVGRE */ +#define NETVSC_GSO_MAX_SIZE 62768 + static int ring_size = 128; module_param(ring_size, int, S_IRUGO); MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)"); @@ -363,6 +366,7 @@ static int netvsc_probe(struct hv_device SET_ETHTOOL_OPS(net, ðtool_ops); SET_NETDEV_DEV(net, &dev->device); + netif_set_gso_max_size(net, NETVSC_GSO_MAX_SIZE); ret = register_netdev(net); if (ret != 0) {