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=-7.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS 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 2C22FC433EF for ; Tue, 14 Sep 2021 03:01:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0922C61108 for ; Tue, 14 Sep 2021 03:01:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237372AbhINDCa (ORCPT ); Mon, 13 Sep 2021 23:02:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48446 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237213AbhINDCa (ORCPT ); Mon, 13 Sep 2021 23:02:30 -0400 Received: from mail-pg1-x532.google.com (mail-pg1-x532.google.com [IPv6:2607:f8b0:4864:20::532]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C3ECBC061574; Mon, 13 Sep 2021 20:01:13 -0700 (PDT) Received: by mail-pg1-x532.google.com with SMTP id k24so11327548pgh.8; Mon, 13 Sep 2021 20:01:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=DsCe+BZFESkDZsqe6u7iZYz+EpftXxtavi4h72VzJL0=; b=VnhszOGJWKfWQf+O+OGEpQ1hmHGptjgf9GZCa88torTr+PLjyUoOSD5z2fKqOK+4/B ZSu4hk5lKgKvx8ric1377rvyrZnEZAl2JQvlWYdwlcr8DA9rFIPzcNIxtt0GFAYrPnyA Qf0fNGNSMSPYKIbUTYbCszYvQak+CKNWuRrtg665fqQxZzmei0Tpe1rtZxLAkYMUizXg 68V8QQJe8mfsPsHz/3o6Lu7+9r4AE+CH49ki2sXDa09osFn5damngbMiHKK0fBHKJ3dD rl8oEJWW9unmoIZkxWv2g9qROeqgRzZRpaps+pQ6WPe0rbKCDY0cXaBNZDOszURs8gCF NTgw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=DsCe+BZFESkDZsqe6u7iZYz+EpftXxtavi4h72VzJL0=; b=AyFAOF/2yBidcc/jNDqoN5CuzVBb5OOOjhH8uePopkAzx6CXrv92uV3kvTxvZfPQC2 LQY/V0TaH12E9sdEePcEKqwHBd07gJknw71tdlQBud2lXoaW1le4fWfq2q8K5HQ7tl3K 4166cDFPfqJsm0ODXR/YUYB6ERhz3z1FIJj/gskD+W9v+8hHD5SKEEFA59BVnEDI+zsm 097neu6hUM+ScxV52v5A5ORsc5llDdRYLnrnwB8GcATWSPnW3N5UjeVS1J269Rl9bhkA BYSwQ9C+uIZyEQKGOL30yDxDxNob19JnPom65GYq3sd75VJ+7NCC2TMahpKVcps3Exff Vmqg== X-Gm-Message-State: AOAM530fM/k+P+f7hQFr2kCZ8UkXd30miCc8ZJxR2l2k2KqPiwbbYqfE KhDlsBj87RScLNrq236AK9+5aOeSvx2M7o4x1g== X-Google-Smtp-Source: ABdhPJzqV2Mb1jqk9XIRMDrDzBl3o2KWNgVs9r4EafBsHrqUtaSwvYdUqcPtToLOnV1C3sAxFLcqdLaw7BV7NRq65Bo= X-Received: by 2002:a05:6a00:2449:b0:43c:4a5e:55a6 with SMTP id d9-20020a056a00244900b0043c4a5e55a6mr2581819pfj.43.1631588473158; Mon, 13 Sep 2021 20:01:13 -0700 (PDT) MIME-Version: 1.0 References: <7faa04f8-cd98-7d8a-2e54-e84e1fe742f7@gmail.com> In-Reply-To: <7faa04f8-cd98-7d8a-2e54-e84e1fe742f7@gmail.com> From: Hao Sun Date: Tue, 14 Sep 2021 11:01:02 +0800 Message-ID: Subject: Re: INFO: task hung in io_uring_cancel_generic To: Pavel Begunkov Cc: Jens Axboe , io-uring@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Pavel Begunkov =E4=BA=8E2021=E5=B9=B49=E6=9C=8813= =E6=97=A5=E5=91=A8=E4=B8=80 =E4=B8=8B=E5=8D=884:30=E5=86=99=E9=81=93=EF=BC= =9A > > On 9/13/21 3:26 AM, Hao Sun wrote: > > Hi > > > > Healer found a C reproducer for this crash ("INFO: task hung in > > io_ring_exit_work"). > > > > HEAD commit: 4b93c544e90e-thunderbolt: test: split up test cases > > git tree: upstream > > console output: > > https://drive.google.com/file/d/1NswMU2yMRTc8-EqbZcVvcJejV92cuZIk/view?= usp=3Dsharing > > kernel config: https://drive.google.com/file/d/1c0u2EeRDhRO-ZCxr9MP2VvA= tJd6kfg-p/view?usp=3Dsharing > > C reproducer: https://drive.google.com/file/d/170wk5_T8mYDaAtDcrdVi2UU9= _dW1894s/view?usp=3Dsharing > > Syzlang reproducer: > > https://drive.google.com/file/d/1eo-jAS9lncm4i-1kaCBkexrjpQHXboBq/view?= usp=3Dsharing > > > > If you fix this issue, please add the following tag to the commit: > > Reported-by: Hao Sun > > I don't see the repro using io_uring at all. Can it be because of > the delay before the warning shows itself? 120 secs, this appeared > after 143. > I think the crash was most likely fixed. Here is what I've done. First, I re-run the whole execution history (https://drive.google.com/file/d/1NswMU2yMRTc8-EqbZcVvcJejV92cuZIk/view?usp= =3Dsharing) with `syz-repro` on latest kernel (6880fa6c5660 Linux 5.15-rc1). The kernel did not crash at all. Then, I re-run the history on the original version of the kernel (4b93c544e90e-thunderbolt: test: split up test cases). It crashed and task hang happened but with a different location ("io_wq_submit_work"). Since `syz-repro` is smart enough and will give prog enough timeout to be executed when the crash type is `Hang` (see https://github.com/google/syzkaller/blob/master/pkg/repro/repro.go#L98), the delay before a warning can be handled properly. However, I'll still keep track of this crash since it was still not reproduced yet. > [...] > > -- > Pavel Begunkov