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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 035A8C2D0CF for ; Mon, 16 Dec 2019 09:18:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D4C5F2080A for ; Mon, 16 Dec 2019 09:18:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726891AbfLPJSv (ORCPT ); Mon, 16 Dec 2019 04:18:51 -0500 Received: from mail1.ugh.no ([178.79.162.34]:51510 "EHLO mail1.ugh.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726875AbfLPJSu (ORCPT ); Mon, 16 Dec 2019 04:18:50 -0500 Received: from localhost (localhost [127.0.0.1]) by mail1.ugh.no (Postfix) with ESMTP id 54E8A24E3BA; Mon, 16 Dec 2019 10:18:49 +0100 (CET) Received: from mail1.ugh.no ([127.0.0.1]) by localhost (catastrophix.ugh.no [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id cDpM2SCLA60o; Mon, 16 Dec 2019 10:18:48 +0100 (CET) Received: from [10.255.64.11] (unknown [185.176.245.143]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: andre@tomt.net) by mail.ugh.no (Postfix) with ESMTPSA id 9C9ED24E3B3; Mon, 16 Dec 2019 10:18:48 +0100 (CET) Subject: Re: [PATCH 4.19 153/306] block: fix the DISCARD request merge (4.19.87+ crash) To: Jack Wang Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, stable , Christoph Hellwig , Ming Lei , Jianchao Wang , Jens Axboe , Sasha Levin References: <20191127203114.766709977@linuxfoundation.org> <20191127203126.845809286@linuxfoundation.org> From: Andre Tomt Message-ID: <4d8343e0-f38a-3e08-edf6-3346b3011ddf@tomt.net> Date: Mon, 16 Dec 2019 10:18:48 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On 16.12.2019 08:42, Jack Wang wrote: > Andre Tomt 于2019年12月14日周六 下午3:24写道： >> >> 4.19.87, 4.19.88, 4.19.89 all lock up frequently on some of my systems. >> The same systems run 5.4.3 fine, so the newer trees are probably OK. >> Reverting this commit on top of 4.19.87 makes everything stable. >> >> To trigger it all I have to do is re-rsyncing a directory tree with some >> changed files churn, it will usually crash in 10 to 30 minutes. >> >> The systems crashing has ext4 filesystem on a two ssd md raid1 mounted >> with the mount option discard. If mounting it without discard, the >> crashes no longer seem to occur. >> >> No oops/panic made it to the ipmi console. I suspect the console is just >> misbehaving and it didnt really livelock. At one point one line of the >> crash made it to the console (kernel BUG at block/blk-core.c:1776), and >> it was enough to pinpoint this commit. Note that the line number might >> be off, as I was attempting a bisect at the time. >> >> This commit also made it to 4.14.x, but I have not tested it. > Hi Andre, > > I noticed one fix is missing for discard merge in 4.19.y > 2a5cf35cd6c5 ("block: fix single range discard merge") > > Can you try if it helps? just "git cherry-pick 2a5cf35cd6c5" Indeed, adding this commit on top a clean 4.19.89 fixes the issue. So far survived about an hour of rsyncing file churn.