From patchwork Mon Apr 8 21:06:46 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matteo Croce X-Patchwork-Id: 1081520 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44dNK34G4gz9sCF for ; Tue, 9 Apr 2019 07:07:03 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726920AbfDHVHC (ORCPT ); Mon, 8 Apr 2019 17:07:02 -0400 Received: from mail-wm1-f65.google.com ([209.85.128.65]:50446 "EHLO mail-wm1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726517AbfDHVHC (ORCPT ); Mon, 8 Apr 2019 17:07:02 -0400 Received: by mail-wm1-f65.google.com with SMTP id z11so919994wmi.0 for ; Mon, 08 Apr 2019 14:07:01 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=iF5YaZOw9A73xNUlwuizd4zKRqsvoxVZycHkFebqv8M=; b=GMo6kq/QgeWHX+ZKwniPIIfp2saUCsEMhWlWLACyHSFNIrYfUHB44y7Rqxy6iBE/mN XkL4M+ZefDjzv6QmrwtJhlT8D6nKHYMZ3r7AA9lbiNKl6Jw964EJoDhcCCIQidc3dkRA DA3ug5fo1kwBuRVlV55mtu2sqx6NchDfyO2jMKGN/uiKXF3EcWdrtkeptZTeJQeXXJuw C4oMi5RZcul9cuy+7wZQAwNb10CjAoU8VujK8/2JeFmZS4YKlATNfHpCakUD0dPNY496 BotRqdihQR+12BIDE6tPteF0QvF4+Br4IE7ZTraQKf6JWz26fOLuQB6lii8vNK4dD3b/ dp5g== X-Gm-Message-State: APjAAAWv7p4ti40MojcIt4Ju3rBwNH36C2MALGbJPJjFBtEznMC/SCtL PeTG8dXqej6EDDXt5lWTUT1AiGrgrMg= X-Google-Smtp-Source: APXvYqz/XPhvfpx7anzdblj4u3/aaMGbSujreyX47dn9tGQ6Ux+EIWRWmPyay9QooM1dLi/GQoPh/A== X-Received: by 2002:a1c:a103:: with SMTP id k3mr19189258wme.8.1554757620222; Mon, 08 Apr 2019 14:07:00 -0700 (PDT) Received: from raver.teknoraver.net (net-93-70-69-135.cust.vodafonedsl.it. [93.70.69.135]) by smtp.gmail.com with ESMTPSA id b9sm18540663wmc.9.2019.04.08.14.06.59 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 08 Apr 2019 14:06:59 -0700 (PDT) From: Matteo Croce To: netdev@vger.kernel.org Cc: Sunil Goutham , Robert Richter , linux-arm-kernel@lists.infradead.org, Ilias Apalodimas , Jesper Dangaard Brouer Subject: [PATCH net v2 1/2] net: thunderx: raise XDP MTU to 1508 Date: Mon, 8 Apr 2019 23:06:46 +0200 Message-Id: <20190408210647.7385-2-mcroce@redhat.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190408210647.7385-1-mcroce@redhat.com> References: <20190408210647.7385-1-mcroce@redhat.com> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The thunderx driver splits frames bigger than 1530 bytes to multiple pages, making impossible to run an eBPF program on it. This leads to a maximum MTU of 1508 if QinQ is in use. The thunderx driver forbids to load an eBPF program if the MTU is higher than 1500 bytes. Raise the limit to 1508 so it is possible to use L2 protocols which need some more headroom. Fixes: 05c773f52b96e ("net: thunderx: Add basic XDP support") Signed-off-by: Matteo Croce --- drivers/net/ethernet/cavium/thunder/nicvf_main.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_main.c b/drivers/net/ethernet/cavium/thunder/nicvf_main.c index 28eac9056211..debc8c861c6b 100644 --- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c +++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c @@ -32,6 +32,13 @@ #define DRV_NAME "nicvf" #define DRV_VERSION "1.0" +/* NOTE: Packets bigger than 1530 are split across multiple pages and XDP needs + * the buffer to be contiguous. Allow XDP to be set up only if we don't exceed + * this value, keeping headroom for the 14 byte Ethernet header and two + * VLAN tags (for QinQ) + */ +#define MAX_XDP_MTU (1530 - ETH_HLEN - VLAN_HLEN * 2) + /* Supported devices */ static const struct pci_device_id nicvf_id_table[] = { { PCI_DEVICE_SUB(PCI_VENDOR_ID_CAVIUM, @@ -1830,8 +1837,10 @@ static int nicvf_xdp_setup(struct nicvf *nic, struct bpf_prog *prog) bool bpf_attached = false; int ret = 0; - /* For now just support only the usual MTU sized frames */ - if (prog && (dev->mtu > 1500)) { + /* For now just support only the usual MTU sized frames, + * plus some headroom for VLAN, QinQ. + */ + if (prog && dev->mtu > MAX_XDP_MTU) { netdev_warn(dev, "Jumbo frames not yet supported with XDP, current MTU %d.\n", dev->mtu); return -EOPNOTSUPP;