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=-11.1 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,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 37EEEC2D0A8 for ; Wed, 23 Sep 2020 11:49:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E035D214D8 for ; Wed, 23 Sep 2020 11:49:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="hVurwq/6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726606AbgIWLtn (ORCPT ); Wed, 23 Sep 2020 07:49:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37070 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726472AbgIWLtn (ORCPT ); Wed, 23 Sep 2020 07:49:43 -0400 Received: from mail-wm1-x343.google.com (mail-wm1-x343.google.com [IPv6:2a00:1450:4864:20::343]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E0A00C0613CE; Wed, 23 Sep 2020 04:49:42 -0700 (PDT) Received: by mail-wm1-x343.google.com with SMTP id y15so6801332wmi.0; Wed, 23 Sep 2020 04:49:42 -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=p4sMBWzXBxVz4HvD3n4l2QIDm0SxypO/fE8nCP81NYo=; b=hVurwq/6/XhFXJ6RoPXK1EGdTYQ6vzFdgejDABeebl0RtKDkmGFD+KdNAxd8/A9JjX ir1KTle+zPq8HVtGgHOCF1NbP340ypt9arNONJOVxUYZquWaqnxmcQ3gb8StBWVA8Dfx v+Lh4dW0ZkzbMTMKpV1Ge813iSjzUYfYJkEl+r1GXJUIWNZxkwLL+CBWP8VYSRtATc/B 5aFvcuMf4SiOPuuhVdVTkUtv7Psy3nn1U3MarmiWquAVZX2jGZcyJ5wMdcqiRck5Yaqx j9tHaigvMiCHJ2lEK5xbq4EFENaf/BSnFna2XopimZ0iURvIzc/UaOIbxIZrLsgIJLPJ U06g== 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=p4sMBWzXBxVz4HvD3n4l2QIDm0SxypO/fE8nCP81NYo=; b=I29Xphixsqtqa74TJL7gYYcJUlrpMsqKdGaGn4dPZbJUF9agfGbYsFJJ6snMU4cJHG vXxnR7SNKjv4xuq5SA4w/KHto0MgG6+/FXuNDHSdVdVdssZRD9G8dwY06/0ETuGx2QCT fjYY6gHbUGckREVu2PnasFyjxhbiae45Cchgb+OFaE5YtV+hYLO7M8LPZmayZH4Kg+Do O5nLXH8vH+frQnDCdrF53NWjgy1J8eJ2F4YJKjUK+0KdZ55Ffjs9zqBbf9V8l4mAav47 YsDkLJ5cZt+ISkj/ogcYA4hjtqVYKuGL/Id3kMnjiwWGtyhQf+M+oFAJ+NRjj6fLyHmZ DVCA== X-Gm-Message-State: AOAM531LbAa31uo288aFm+KKxM08G8WZb7/4T7wwlkQ2FgfrfC+WS7j2 ijiG0XTZM9es8N32G+1r3D8gpKZN2Js= X-Google-Smtp-Source: ABdhPJwSy8djRzattquH/FjML2gk62PklGKieE8AHEPIh5I6VIm/LdLDkYCYpQ99B8eNnnr/FZ2mRA== X-Received: by 2002:a7b:c4d9:: with SMTP id g25mr6072703wmk.15.1600861781360; Wed, 23 Sep 2020 04:49:41 -0700 (PDT) Received: from ?IPv6:2003:ea:8f23:5700:c43a:de91:4527:c1ba? (p200300ea8f235700c43ade914527c1ba.dip0.t-ipconnect.de. [2003:ea:8f23:5700:c43a:de91:4527:c1ba]) by smtp.googlemail.com with ESMTPSA id i14sm241690wml.24.2020.09.23.04.49.40 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 23 Sep 2020 04:49:40 -0700 (PDT) Subject: Re: [PATCH] Revert "net: linkwatch: add check for netdevice being present to linkwatch_do_dev" To: Saeed Mahameed , Geert Uytterhoeven , Florian Fainelli , Andrew Lunn , "David S . Miller" , Jakub Kicinski Cc: Gaku Inami , Yoshihiro Shimoda , netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20200901150237.15302-1-geert+renesas@glider.be> <7bfebfdc0d7345c4612124ff00e20eebb0ff6cd9.camel@kernel.org> From: Heiner Kallweit Message-ID: <3d9176a6-c93e-481c-5877-786f5e6aaef8@gmail.com> Date: Wed, 23 Sep 2020 13:49:35 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <7bfebfdc0d7345c4612124ff00e20eebb0ff6cd9.camel@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 18.09.2020 19:58, Saeed Mahameed wrote: > On Tue, 2020-09-01 at 17:02 +0200, Geert Uytterhoeven wrote: >> This reverts commit 124eee3f6955f7aa19b9e6ff5c9b6d37cb3d1e2c. >> >> Inami-san reported that this commit breaks bridge support in a Xen >> environment, and that reverting it fixes this. >> >> During system resume, bridge ports are no longer enabled, as that >> relies >> on the receipt of the NETDEV_CHANGE notification. This notification >> is >> not sent, as netdev_state_change() is no longer called. >> >> Note that the condition this commit intended to fix never existed >> upstream, as the patch triggering it and referenced in the commit was >> never applied upstream. Hence I can confirm s2ram on r8a73a4/ape6evm >> and sh73a0/kzm9g works fine before/after this revert. >> >> Reported-by Gaku Inami >> Signed-off-by: Geert Uytterhoeven >> --- >> net/core/link_watch.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/net/core/link_watch.c b/net/core/link_watch.c >> index 75431ca9300fb9c4..c24574493ecf95e6 100644 >> --- a/net/core/link_watch.c >> +++ b/net/core/link_watch.c >> @@ -158,7 +158,7 @@ static void linkwatch_do_dev(struct net_device >> *dev) >> clear_bit(__LINK_STATE_LINKWATCH_PENDING, &dev->state); >> >> rfc2863_policy(dev); >> - if (dev->flags & IFF_UP && netif_device_present(dev)) { >> + if (dev->flags & IFF_UP) { > > So with your issue the devices is both IFF_UP and !present ? how so ? > I think you should look into that. > > I am ok with removing the "dev present" check from here just because we > shouldn't be expecting IFF_UP && !present .. such thing must be a bug > somewhere else. > >> if (netif_carrier_ok(dev)) >> dev_activate(dev); >> else > In __dev_close_many() we call ndo_stop() whilst IFF_UP is still set. ndo_stop() may detach the device and bring down the PHY, resulting in an async link change event that calls dev_get_stats(). The latter call may have a problem if the device is detached. In a first place I'd consider such a case a network driver bug (ndo_get_stats/64 should check for device presence if depending on it). The additional check in linkwatch_do_dev() was meant to protect from such driver issues.