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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS 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 0FE7BC4360F for ; Wed, 3 Apr 2019 12:18:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D3DE72084B for ; Wed, 3 Apr 2019 12:18:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="EzcVJRmD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726310AbfDCMSd (ORCPT ); Wed, 3 Apr 2019 08:18:33 -0400 Received: from mail-wr1-f66.google.com ([209.85.221.66]:40857 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726074AbfDCMSd (ORCPT ); Wed, 3 Apr 2019 08:18:33 -0400 Received: by mail-wr1-f66.google.com with SMTP id h4so21000116wre.7 for ; Wed, 03 Apr 2019 05:18:32 -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=cUXPR467uDSuHAPJ/qsTcA8ylP+O55wuLpzbJfT30ow=; b=EzcVJRmDi+pASFizfjNqRTJT0hJ3t9D3M5JVV294lgWCsMo1ZYzjg1w+/m4vDKrfhS vOz2t1092AGel2DQVyQ4JKMcu5o2u/YJdt9rrOaA/QTw7eRsE5c4OUYyRAWHBn3IoxPo GUsGQvWYiRq3yD/U4y/lT2d3ITAW8R1nmUmhHBJbykUFo+Uia5ZC6PvRBjlYKngymwp3 C7kZ+35OjlPre6nICmozHey0M+W5Z8Xe+6L0BHjEgUny9SwYs3yvug7hC+YfA8Rvbiih mAZ+YRz8aCC9kF1V2Jm2NZdha91OkaV6YhPq7boAfgkFbSNuD7IMrxm9LZB89Rwxw2vp hHEA== 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=cUXPR467uDSuHAPJ/qsTcA8ylP+O55wuLpzbJfT30ow=; b=kSm10JYZFZDVF4+7bIsYtlr9NKAHts100bUoThAmN3YU+iQDiXY+mN+E9Z3B4bCjoZ 1598jfnvcJsE6J2qby1ggX3lmB+OKaI/xjic9kIkv9IhUb0zST+A3gR8YQyK4TXYyP+k NdGhff/CqrTJ8SBvfgwnIO5m0mB2KUyhjVWcMTbvlL+R5tuHoru8eSF7vaYvV9APRaqs fMluZAvJQtHLXjYsSDYGAF21lPked87Zb2vXMff7rBF6NgKUdPZ5gtRTtRlgFv4Dqafg cAbvccVy7qV8eNBvT1mOX7q+CeScFpTBETCwrafjNyTbwbY4HQCmL5zuqJ/QNZCJcWDF w+Mg== X-Gm-Message-State: APjAAAXn73iG2PHteYLFhLXbw++8QN94WIeT2af7DqXV0zCis265RdDk yRQAInTXFFB5u6/CSM3EgBJAlcUB X-Google-Smtp-Source: APXvYqzvIb9W4scmOkKbRcwR/06M2druXfiGY55wYeoskcrA4KYXqa9OpZ3YqbHJQ75Vm7pR1LnY2A== X-Received: by 2002:adf:ec4e:: with SMTP id w14mr18884050wrn.53.1554293911678; Wed, 03 Apr 2019 05:18:31 -0700 (PDT) Received: from [192.168.8.147] (107.82.136.77.rev.sfr.net. [77.136.82.107]) by smtp.gmail.com with ESMTPSA id t15sm22872228wmt.2.2019.04.03.05.18.29 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 03 Apr 2019 05:18:30 -0700 (PDT) Subject: Re: [PATCH net-next] net: use correct this_cpu primitive in dev_recursion_level To: Florian Westphal , netdev@vger.kernel.org Cc: syzbot+51471b4aae195285a4a3@syzkaller.appspotmail.com References: <000000000000db3c59058595f0ac@google.com> <20190403062835.23920-1-fw@strlen.de> From: Eric Dumazet Message-ID: <417c82a9-1a53-4a2a-68ee-4e52552a8a6d@gmail.com> Date: Wed, 3 Apr 2019 05:18:28 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20190403062835.23920-1-fw@strlen.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 04/02/2019 11:28 PM, Florian Westphal wrote: > syzbot reports: > BUG: using __this_cpu_read() in preemptible code: > caller is dev_recursion_level include/linux/netdevice.h:3052 [inline] > __this_cpu_preempt_check+0x246/0x270 lib/smp_processor_id.c:47 > dev_recursion_level include/linux/netdevice.h:3052 [inline] > ip6_skb_dst_mtu include/net/ip6_route.h:245 [inline] > > I erronously downgraded a this_cpu_read to __this_cpu_read when > moving dev_recursion_level() around. > Reviewed-by: Eric Dumazet