From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E89B5C6377C for ; Thu, 22 Jul 2021 03:57:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D0C8861222 for ; Thu, 22 Jul 2021 03:57:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231154AbhGVDQb (ORCPT ); Wed, 21 Jul 2021 23:16:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42616 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229900AbhGVDQ3 (ORCPT ); Wed, 21 Jul 2021 23:16:29 -0400 Received: from mail-pj1-x1034.google.com (mail-pj1-x1034.google.com [IPv6:2607:f8b0:4864:20::1034]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 740C9C061575; Wed, 21 Jul 2021 20:57:05 -0700 (PDT) Received: by mail-pj1-x1034.google.com with SMTP id pf12-20020a17090b1d8cb0290175c085e7a5so2392070pjb.0; Wed, 21 Jul 2021 20:57:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=eFaQS4/KTkRNWySIsqDTE+2ou4eK63jeGeUW05LyArI=; b=WRrHxI57vFLy9CLbw9XY3i3RwyAa+dasAPV46FWPT0Uzy0dVUroR8dLaJw2FgzW9Fl eI9d4HMfWtixNbkqAp/fNjpfxXSJM/4BmYeuT9Tc3Ha/9sY/nNTDcUFygJtTLnxE7Xid Wit0oyGxrkoKn1DUjdtgtTiNyNVYkT/n5WfaFkQYjK9TiTWdV6RsUtj9cQ++QHFJdApa mqLVuGWVCjqySMyNh1X0WrwO+F6Etc7xU5AZ6LCeyI3XZZxjOcNNim/Y/80w6mdERdH4 IQmxnnTpdtiXw3XXPl4QqUTW1xwt7M7GK4h20lByfRgPHYlOGguOCSMq92fJa6cV72J2 zIVA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=eFaQS4/KTkRNWySIsqDTE+2ou4eK63jeGeUW05LyArI=; b=IPkwxoL7FL3WG8KF4j3+xL2xyFHbATmOT9NYcYy8pc4C1jcBYNZpc2enqarh6U25H3 0pdx+pHHOhQF2wonIiPR2mr3yMy03+iTnGD5QFrBWzb7VOkhOwev4qADGN0lExj8JvLM 03bJqOiuUe8GkJx4Xibtyr64sQw9gxmEDPHv5Muzf6cXCmCxNYUEWv9L/EYCiQ91oJyl +s77eBzexZ9T3w6MhUbzq+ipdiS5rjPAOGFMrUUNV4LtlkWZONssMu9o95s+iEENrBTE ygi8+DUg7KUhos8v4hTHn0e7siTa8C+GheDXTl7eUycad0ed+3hSZ/WvRrukjYfYwt6u Pr9A== X-Gm-Message-State: AOAM530JZ60cUNC2bo25M94mJnmwiw6cBhXozlWTnuLEHG1duIO+tgJJ M5tVU2agUVWjoPCH24eKKjf6fQpiAJA= X-Google-Smtp-Source: ABdhPJz5Xo38lE2dm/V/uqEGpsaVAeNM+tyhZ8R0tGLZYIrGltFKG/w+3qGJePF+G/QlHK45m80cxg== X-Received: by 2002:a17:90a:e54a:: with SMTP id ei10mr6981023pjb.1.1626926224708; Wed, 21 Jul 2021 20:57:04 -0700 (PDT) Received: from [10.230.31.46] ([192.19.223.252]) by smtp.gmail.com with ESMTPSA id x10sm20484384pfh.56.2021.07.21.20.56.59 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 21 Jul 2021 20:57:03 -0700 (PDT) Subject: Re: [PATCH v2 1/2] net: dsa: ensure linearized SKBs in case of tail taggers To: Vladimir Oltean , Lino Sanfilippo Cc: woojung.huh@microchip.com, UNGLinuxDriver@microchip.com, andrew@lunn.ch, vivien.didelot@gmail.com, davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20210721215642.19866-1-LinoSanfilippo@gmx.de> <20210721215642.19866-2-LinoSanfilippo@gmx.de> <20210721233549.mhqlrt3l2bbyaawr@skbuf> From: Florian Fainelli Message-ID: <8460fa10-6db7-273c-a2c2-9b54cc660d9a@gmail.com> Date: Wed, 21 Jul 2021 20:56:56 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 MIME-Version: 1.0 In-Reply-To: <20210721233549.mhqlrt3l2bbyaawr@skbuf> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/21/2021 4:35 PM, Vladimir Oltean wrote: > On Wed, Jul 21, 2021 at 11:56:41PM +0200, Lino Sanfilippo wrote: >> The function skb_put() that is used by tail taggers to make room for the >> DSA tag must only be called for linearized SKBS. However in case that the >> slave device inherited features like NETIF_F_HW_SG or NETIF_F_FRAGLIST the >> SKB passed to the slaves transmit function may not be linearized. >> Avoid those SKBs by clearing the NETIF_F_HW_SG and NETIF_F_FRAGLIST flags >> for tail taggers. >> Furthermore since the tagging protocol can be changed at runtime move the >> code for setting up the slaves features into dsa_slave_setup_tagger(). >> >> Suggested-by: Vladimir Oltean >> Signed-off-by: Lino Sanfilippo >> --- >> net/dsa/slave.c | 14 +++++++++----- >> 1 file changed, 9 insertions(+), 5 deletions(-) >> >> diff --git a/net/dsa/slave.c b/net/dsa/slave.c >> index 22ce11cd770e..ae2a648ed9be 100644 >> --- a/net/dsa/slave.c >> +++ b/net/dsa/slave.c >> @@ -1808,6 +1808,7 @@ void dsa_slave_setup_tagger(struct net_device *slave) >> struct dsa_slave_priv *p = netdev_priv(slave); >> const struct dsa_port *cpu_dp = dp->cpu_dp; >> struct net_device *master = cpu_dp->master; >> + const struct dsa_switch *ds = dp->ds; >> >> slave->needed_headroom = cpu_dp->tag_ops->needed_headroom; >> slave->needed_tailroom = cpu_dp->tag_ops->needed_tailroom; >> @@ -1819,6 +1820,14 @@ void dsa_slave_setup_tagger(struct net_device *slave) >> slave->needed_tailroom += master->needed_tailroom; >> >> p->xmit = cpu_dp->tag_ops->xmit; >> + >> + slave->features = master->vlan_features | NETIF_F_HW_TC; >> + if (ds->ops->port_vlan_add && ds->ops->port_vlan_del) >> + slave->features |= NETIF_F_HW_VLAN_CTAG_FILTER; >> + slave->hw_features |= NETIF_F_HW_TC; >> + slave->features |= NETIF_F_LLTX; >> + if (slave->needed_tailroom) >> + slave->features &= ~(NETIF_F_SG | NETIF_F_FRAGLIST); >> } >> >> static struct lock_class_key dsa_slave_netdev_xmit_lock_key; >> @@ -1881,11 +1890,6 @@ int dsa_slave_create(struct dsa_port *port) >> if (slave_dev == NULL) >> return -ENOMEM; >> >> - slave_dev->features = master->vlan_features | NETIF_F_HW_TC; >> - if (ds->ops->port_vlan_add && ds->ops->port_vlan_del) >> - slave_dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER; >> - slave_dev->hw_features |= NETIF_F_HW_TC; >> - slave_dev->features |= NETIF_F_LLTX; >> slave_dev->ethtool_ops = &dsa_slave_ethtool_ops; >> if (!is_zero_ether_addr(port->mac)) >> ether_addr_copy(slave_dev->dev_addr, port->mac); >> -- >> 2.32.0 >> > > I would have probably changed the code in dsa_slave_create just like > this: > > - slave->features = master->vlan_features | NETIF_F_HW_TC; > + slave->features = NETIF_F_HW_TC; > ... > - slave_dev->vlan_features = master->vlan_features; > > and in dsa_slave_setup_tagger: > > + vlan_features = master->vlan_features; > + slave->features &= ~vlan_features; > + if (slave->needed_tailroom) > + vlan_features &= ~(NETIF_F_SG | NETIF_F_FRAGLIST); > + slave->features |= vlan_features; > + slave->vlan_features = vlan_features; > > no need to move around NETIF_F_HW_TC and NETIF_F_LLTX. Makes sense? > > And I would probably add: > > Fixes: 91da11f870f0 ("net: Distributed Switch Architecture protocol support") Agreed, with those fixed: Reviewed-by: Florian Fainelli -- Florian