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=-14.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 6E01EC433DF for ; Mon, 19 Oct 2020 20:03:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2861C22365 for ; Mon, 19 Oct 2020 20:03:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="rFDnMP98" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728430AbgJSUDC (ORCPT ); Mon, 19 Oct 2020 16:03:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726385AbgJSUDC (ORCPT ); Mon, 19 Oct 2020 16:03:02 -0400 Received: from mail-ej1-x642.google.com (mail-ej1-x642.google.com [IPv6:2a00:1450:4864:20::642]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE4D4C0613CE; Mon, 19 Oct 2020 13:03:01 -0700 (PDT) Received: by mail-ej1-x642.google.com with SMTP id z5so802583ejw.7; Mon, 19 Oct 2020 13:03:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=18BK5QABG5QnCnKw4efSXgYTiRd7IX1w5DP5yy+9I9I=; b=rFDnMP98hbleUk2ilEizlHXP674Bq3lV8+edQSDV3d11umzEPWtjx8SQmsPOSlZWEV yDTXSwJg9qZUAxfjAA98CYUBOQJWs0+RPJry16l8727hgHMJc1SaDjpT+cHnZNNGoUCh 1Lluv4t5NPXLJpoVbn/OxAJEmguv1vLKfpxlwThO4J8lCmVKct06cv2k2wdXpgHn5GrM hGLM3Eo1Gmh5tZj/CuOvR1pyFXcdIBr8iJupLy6M9rWqzWb4fAOdlqdDw7LOXXTKLBwS +hQvI24VZiYj6QWwZlN2+VCV+F1bB4ZaB+h/35o/7iVrnd3+AJ9stXWE4eiNbcmBRRpr 7Ckw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=18BK5QABG5QnCnKw4efSXgYTiRd7IX1w5DP5yy+9I9I=; b=PPi53IAMhUSoTVYs1+WU00aFZ0lg+LnfGB84nNOUY3baTWPithoPVTxLbRX0GmHXY8 2aXjyNvZ3jPMddsit53mw/4F2yGZ5LnVJvi4uUmSqLZkTQxUdtjQPQuiHOAWPU2cvcdS VsCCPeVMMZ9EokrJBJ117LM8M5+SwHvWBVLigiCaWgcNuEwCV/cJge/iAJ5BjbP1AAtw C3x86uOn2VNUt2e2a6hZHofSqoI1T08ipwaclWrJAMEF42PIP79jDXczd6c8Eu2zKFr2 U9hJ6GQp3Fy/YgFn8Rz9ql1+XT+RZtfvwkmqapJAw16T1fINcuS1U4gjPPgUbzZkU9PW Ogfg== X-Gm-Message-State: AOAM533ZMcq3t8RAyXcRNC8VXdeirQfWyYHl3NZl2A0fqY5/SK5pJG9c 8nJexTcDMd3TpLft7FGGqsk= X-Google-Smtp-Source: ABdhPJzkCeWXmQnav763Ok076vRwgRnjdn4adsktoySJMo8mM09SCNxvBPJVR7s4jDoKLkHpD+5uWQ== X-Received: by 2002:a17:906:95d1:: with SMTP id n17mr1605193ejy.75.1603137780335; Mon, 19 Oct 2020 13:03:00 -0700 (PDT) Received: from skbuf ([188.26.174.215]) by smtp.gmail.com with ESMTPSA id v14sm834988edy.68.2020.10.19.13.02.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Oct 2020 13:02:59 -0700 (PDT) Date: Mon, 19 Oct 2020 23:02:58 +0300 From: Vladimir Oltean To: Florian Fainelli Cc: netdev@vger.kernel.org, kuba@kernel.org, "David S. Miller" , Eric Dumazet , Yunjian Wang , open list Subject: Re: [PATCH net] net: Have netpoll bring-up DSA management interface Message-ID: <20201019200258.jrtymxikwrijkvpq@skbuf> References: <20201019171746.991720-1-f.fainelli@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201019171746.991720-1-f.fainelli@gmail.com> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, Oct 19, 2020 at 10:17:44AM -0700, Florian Fainelli wrote: > These devices also do not utilize the upper/lower linking so the > check about the netpoll device having upper is not going to be a > problem. They do as of 2f1e8ea726e9 ("net: dsa: link interfaces with the DSA master to get rid of lockdep warnings"), don't they? The question is why that doesn't work, and the answer is, I believe, that the linkage needs to be the other way around than DSA has it. > > The solution adopted here is identical to the one done for > net/ipv4/ipconfig.c with 728c02089a0e ("net: ipv4: handle DSA enabled > master network devices"), with the network namespace scope being > restricted to that of the process configuring netpoll. ... and further restricted to the only network namespace that DSA supports. As a side note, we should declare NETIF_F_NETNS_LOCAL_BIT for DSA interfaces. > > Fixes: 04ff53f96a93 ("net: dsa: Add netconsole support") > Signed-off-by: Florian Fainelli > --- > net/core/netpoll.c | 22 ++++++++++++++++++---- > 1 file changed, 18 insertions(+), 4 deletions(-) > > diff --git a/net/core/netpoll.c b/net/core/netpoll.c > index c310c7c1cef7..960948290001 100644 > --- a/net/core/netpoll.c > +++ b/net/core/netpoll.c > @@ -29,6 +29,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -657,15 +658,15 @@ EXPORT_SYMBOL_GPL(__netpoll_setup); > > int netpoll_setup(struct netpoll *np) > { > - struct net_device *ndev = NULL; > + struct net_device *ndev = NULL, *dev = NULL; > + struct net *net = current->nsproxy->net_ns; > struct in_device *in_dev; > int err; > > rtnl_lock(); > - if (np->dev_name[0]) { > - struct net *net = current->nsproxy->net_ns; > + if (np->dev_name[0]) > ndev = __dev_get_by_name(net, np->dev_name); > - } > + > if (!ndev) { > np_err(np, "%s doesn't exist, aborting\n", np->dev_name); > err = -ENODEV; > @@ -673,6 +674,19 @@ int netpoll_setup(struct netpoll *np) > } > dev_hold(ndev); > > + /* bring up DSA management network devices up first */ > + for_each_netdev(net, dev) { > + if (!netdev_uses_dsa(dev)) > + continue; > + > + err = dev_change_flags(dev, dev->flags | IFF_UP, NULL); > + if (err < 0) { > + np_err(np, "%s failed to open %s\n", > + np->dev_name, dev->name); > + goto put; > + } > + } > + Completely crazy and outlandish idea, I know, but what's wrong with doing this in DSA? diff --git a/net/dsa/slave.c b/net/dsa/slave.c index 33788b5c1742..e5927c4498a2 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -68,8 +68,14 @@ static int dsa_slave_open(struct net_device *dev) struct dsa_port *dp = dsa_slave_to_port(dev); int err; - if (!(master->flags & IFF_UP)) - return -ENETDOWN; + if (!(master->flags & IFF_UP)) { + err = dev_change_flags(master, master->flags | IFF_UP, NULL); + if (err < 0) { + netdev_err(dev, "failed to open master %s\n", + master->name); + goto out; + } + } if (!ether_addr_equal(dev->dev_addr, master->dev_addr)) { err = dev_uc_add(master, dev->dev_addr); -- 2.25.1 It has the benefit that user space can now remove DSA-specific workarounds, like systemd-networkd with BindCarrier: https://github.com/systemd/systemd/issues/7478 And we could remove one of the 2 bullets in the "Common pitfalls using DSA setups" chapter: https://www.kernel.org/doc/Documentation/networking/dsa/dsa.txt And.... We could remove the DSA workaround from net/ipv4/ipconfig.c as well. Just saying. > if (netdev_master_upper_dev_get(ndev)) { > np_err(np, "%s is a slave device, aborting\n", np->dev_name); > err = -EBUSY; > -- > 2.25.1 >