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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 CED8AC33CA1 for ; Thu, 9 Jan 2020 15:32:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A50FD2072E for ; Thu, 9 Jan 2020 15:32:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578583950; bh=e+8teUutDcTrOf1C5tq1dzQr8Tjsy4MZMpCRFIYHJuc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=CYWTSkUnvch1yW601QRRtSWhFl5cqbBo7wJtZH7MafUo01x6Z9Krlw2LVJ7nIXRd4 5OfEuMH0aAs9zSjSS9he7hqHskZjUqY3ySMDFewT94utUFpvw9XEfC3L9lu7FdlUYm HacUKGwscRYAqxnIpkmAlYlSt16Wp0/0JN2diK2w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732464AbgAIPc2 (ORCPT ); Thu, 9 Jan 2020 10:32:28 -0500 Received: from mail.kernel.org ([198.145.29.99]:39762 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729589AbgAIPc2 (ORCPT ); Thu, 9 Jan 2020 10:32:28 -0500 Received: from localhost (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4FFE92072A; Thu, 9 Jan 2020 15:32:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578583947; bh=e+8teUutDcTrOf1C5tq1dzQr8Tjsy4MZMpCRFIYHJuc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=x0+zT5fu5S2nCgP35Kc9swptcQDkCVh27Z9qnkoMWKBJy5yQ7KwHux13C4WwVsxeU kXmNgtSCnHfhTbdZsigqPxu8OO2SYXWmcDvaPxHkFWk+T1D9WIDDjy+IBzf6h0yK1r 0e/PzjaCU6YFd00U72+HOKb8jUFv5SL+NSoSDeTs= Date: Thu, 9 Jan 2020 10:32:26 -0500 From: Sasha Levin To: Naresh Kamboju Cc: Greg Kroah-Hartman , open list , linux- stable , Eric Dumazet , Michal Kubecek , Firo Yang , Jakub Kicinski , rcu@vger.kernel.org, Netdev , lkft-triage@lists.linaro.org Subject: Re: [PATCH AUTOSEL 4.19 46/84] tcp/dccp: fix possible race __inet_lookup_established() Message-ID: <20200109153226.GG1706@sasha-vm> References: <20191227174352.6264-1-sashal@kernel.org> <20191227174352.6264-46-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, Jan 02, 2020 at 01:31:22PM +0530, Naresh Kamboju wrote: >On Fri, 27 Dec 2019 at 23:17, Sasha Levin wrote: >> >> From: Eric Dumazet >> >> [ Upstream commit 8dbd76e79a16b45b2ccb01d2f2e08dbf64e71e40 ] >> >> Michal Kubecek and Firo Yang did a very nice analysis of crashes >> happening in __inet_lookup_established(). >> >> Since a TCP socket can go from TCP_ESTABLISH to TCP_LISTEN >> (via a close()/socket()/listen() cycle) without a RCU grace period, >> I should not have changed listeners linkage in their hash table. >> >> They must use the nulls protocol (Documentation/RCU/rculist_nulls.txt), >> so that a lookup can detect a socket in a hash list was moved in >> another one. >> >> Since we added code in commit d296ba60d8e2 ("soreuseport: Resolve >> merge conflict for v4/v6 ordering fix"), we have to add >> hlist_nulls_add_tail_rcu() helper. > >The kernel panic reported on all devices, >While running LTP syscalls accept* test cases on stable-rc-4.19 branch kernel. >This report log extracted from qemu_x86_64. > >Reverting this patch re-solved kernel crash. I'll drop it until we can look into what's happening here, thanks! -- Thanks, Sasha