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=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 AF8CDC432C0 for ; Tue, 19 Nov 2019 04:34:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8168622319 for ; Tue, 19 Nov 2019 04:34:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="QxRyOWEA" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727500AbfKSEe2 (ORCPT ); Mon, 18 Nov 2019 23:34:28 -0500 Received: from mail-pl1-f176.google.com ([209.85.214.176]:39227 "EHLO mail-pl1-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727354AbfKSEe2 (ORCPT ); Mon, 18 Nov 2019 23:34:28 -0500 Received: by mail-pl1-f176.google.com with SMTP id o9so11040576plk.6 for ; Mon, 18 Nov 2019 20:34:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:from:to:cc:references:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=rkdEpR62sDVJxgsklhz1UnFEmVbcNibLh8/QnTcfFDc=; b=QxRyOWEATY2cC2tVR5io3QZcV+0POPsUjI9K7u3AsC/BnxcStwWEfJUlXHl0Vi791Q Io6aVIdnaAJRnpxHlJEpBsiNM58/23Ti/xY5Ge5bZp80Z0bCNHXJtcFtHdbiDZenPI09 PKFZNRtVzPyhTH/hzpAn0eFyDgIcZyTbRgiMdIYuOqaMSVnEoyAlU5RDlhVmnlGGLMAW j2nw7EU7CUklvXki/4UaU2nPoGgjr+laZc020JOvx3acdSInUg46Qu6OC5UXAJF9LXdS kmSfLrmPjbYJBiFx0vHl43XvtDqbJEVpR8AGeGRQbXBHGq41ywd0nP0brZuC6EyE47IC brHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:references:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=rkdEpR62sDVJxgsklhz1UnFEmVbcNibLh8/QnTcfFDc=; b=SYti2v+CjzUnnQ4jjHld2/+Lli7F6pgcsjql4hyhhzLITKGFZ6G6SK2IWIM+8oUhSU IKZEPbuTpSpJiNI+Z7MtdggNgbFHW2KibebZxxGXiwaYIV5N0ne3gZ6jmhIw7/MFt2Pa Omn8jnntwycOM3NOjku4/WWBEGVKdGL43EHFrn0E9nXzi0VdRj5VpHp9hm1sJOn2iztS ISNFmN4OUJ07nV4D6mefFr/vQmruMRYfW5fQ8rwSBRkt0Izx0VcHZ3JqanQ1ciOaRdFt 8qm6Hp9KgeRjsNcgUsI5oJRtNUd5sT+UwZygrejIj71YeP2c836TADYd/ZXC8S4gk9xn XtXQ== X-Gm-Message-State: APjAAAWNubgl1CCqIwJrkWVPHHylfbEbwb5o5gEqUVyTSS7yUFaNO2P6 JRsUv7/Hh3r42GTpZ6nCaGH/4w== X-Google-Smtp-Source: APXvYqwS6dQ3WixHS9SBX1WTB0MYVtzBe/zIaYNktn/PyxM7sW/RB1GkPzkJraCwg45ZOoaYSWA9Lg== X-Received: by 2002:a17:90a:22a6:: with SMTP id s35mr3454079pjc.3.1574138067544; Mon, 18 Nov 2019 20:34:27 -0800 (PST) Received: from [192.168.1.188] ([66.219.217.79]) by smtp.gmail.com with ESMTPSA id s2sm21838748pgv.48.2019.11.18.20.34.24 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 18 Nov 2019 20:34:26 -0800 (PST) Subject: Re: INFO: task hung in io_wq_destroy From: Jens Axboe To: Eric Biggers Cc: syzbot , andriy.shevchenko@linux.intel.com, davem@davemloft.net, f.fainelli@gmail.com, gregkh@linuxfoundation.org, idosch@mellanox.com, kimbrownkd@gmail.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, petrm@mellanox.com, syzkaller-bugs@googlegroups.com, tglx@linutronix.de, viro@zeniv.linux.org.uk, wanghai26@huawei.com, yuehaibing@huawei.com References: <000000000000f86a4f0595fdb152@google.com> <20191119022330.GC3147@sol.localdomain> Message-ID: Date: Mon, 18 Nov 2019 21:34:22 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 11/18/19 8:15 PM, Jens Axboe wrote: > On 11/18/19 7:23 PM, Eric Biggers wrote: >> Hi Jens, >> >> On Mon, Oct 28, 2019 at 03:00:08PM -0600, Jens Axboe wrote: >>> This is fixed in my for-next branch for a few days at least, unfortunately >>> linux-next is still on the old one. Next version should be better. >> >> This is still occurring on linux-next. Here's a report on next-20191115 from >> https://syzkaller.appspot.com/text?tag=CrashReport&x=16fa3d1ce00000 > > Hmm, I'll take a look. Looking at the reproducer, it's got a massive > sleep at the end. I take it this triggers before that time actually > passes? Because that's around 11.5 days of sleep. > > No luck reproducing this so far, I'll try on linux-next. I see what it is - if the io-wq is setup and torn down before the manager thread is started, then we won't create the workers we already expected. The manager thread will exit without doing anything, but teardown will wait for the expected workers to exit before being allowed to proceed. That never happens. I've got a patch for this, but I'll test it a bit and send it out tomorrow. -- Jens Axboe