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_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 5BA9EC46475 for ; Mon, 5 Nov 2018 10:40:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD3652086C for ; Mon, 5 Nov 2018 10:40:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=szeredi.hu header.i=@szeredi.hu header.b="QmP8xmVG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AD3652086C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=szeredi.hu Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729039AbeKET7q (ORCPT ); Mon, 5 Nov 2018 14:59:46 -0500 Received: from mail-io1-f68.google.com ([209.85.166.68]:41184 "EHLO mail-io1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728983AbeKET7p (ORCPT ); Mon, 5 Nov 2018 14:59:45 -0500 Received: by mail-io1-f68.google.com with SMTP id a5-v6so6110878ioq.8 for ; Mon, 05 Nov 2018 02:40:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=szeredi.hu; s=google; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=+1jpJyS+61EDhtmubHqx1H4A26JAsgUpvaVqS91pUq4=; b=QmP8xmVG8wLlzbBqQO7GDz5sBPmwuvSFkRzsouGnw0wOTMlMPv/T9ButDxkzUH6AAL KoniyvKXR1PX9fDIwH9uVCt3UXhfnmhGt+tg6+vU73nMXq8kVnVPweLt3RnKXCiyIPgk 2jS+IFOtQkXwebnWwqTAu0RGN/qgKQUSTr5ME= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=+1jpJyS+61EDhtmubHqx1H4A26JAsgUpvaVqS91pUq4=; b=CZoHMWIzLWBGJX2RDri8gAkh7wTAfIZUSXQi+GVQQccf0HmOPGqZSCgekQdlbEqisL QAyNDjfb7fhauEe4vsD8CaeCZVDMC+KivzVBG9NfbCuEgZ5pUoYsdxI3JZJyZ8+TOHb0 7ajWS7cqe6Ihxv4NHxvepZOdd1ZeNa8sAhI1TSWYl1iFZ12m4MPTx7VHfhFwqm1kTsXX Eci2TDT8YneePrYcURgkmhhHWtNssoEw+LGy3CJ6Qc4APDz4+zITwE/vd3UkYEgNl5WE 6kw35QOHY6k/1cIEMu/7ZyNuGcmUZR7RIUmnyy04FeVazdO7v96mb6I+Blw9xpz9OlRZ zl5Q== X-Gm-Message-State: AGRZ1gIw65BGUXCfjdYs2eEiDf6UuzarCNYF0hU4mtknkx2USWzPBJh9 OO9Hl7fMKiADrN/2XNzCDbLfRdlqLDDSCnMgoHGrcw== X-Google-Smtp-Source: AJdET5e8Xr7+Pa70Hep7EWyGUHVUlzEIYre5tgu/gG/fflVoxr6ZXL4PFVo7Sgwhix3cF+9mtDHbQX7/lziqBeZJLmA= X-Received: by 2002:a5e:8b42:: with SMTP id z2-v6mr14786581iom.144.1541414441444; Mon, 05 Nov 2018 02:40:41 -0800 (PST) MIME-Version: 1.0 Received: by 2002:a6b:ac42:0:0:0:0:0 with HTTP; Mon, 5 Nov 2018 02:40:40 -0800 (PST) X-Originating-IP: [94.21.144.184] In-Reply-To: References: <000000000000c25cca0579982a05@google.com> From: Miklos Szeredi Date: Mon, 5 Nov 2018 11:40:40 +0100 Message-ID: Subject: Re: INFO: task hung in fuse_sb_destroy To: Dmitry Vyukov Cc: syzbot , linux-fsdevel , LKML , syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 1, 2018 at 12:05 PM, Dmitry Vyukov wrote: > On Thu, Nov 1, 2018 at 11:49 AM, syzbot > wrote: >> Hello, >> >> syzbot found the following crash on: >> >> HEAD commit: 59fc453b21f7 Merge branch 'akpm' (patches from Andrew) >> git tree: upstream >> console output: https://syzkaller.appspot.com/x/log.txt?x=15fb2447400000 >> kernel config: https://syzkaller.appspot.com/x/.config?x=ea045471e4c756e8 >> dashboard link: https://syzkaller.appspot.com/bug?extid=6339eda9cb4ebbc4c37b >> compiler: gcc (GCC) 8.0.1 20180413 (experimental) >> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=178a105d400000 >> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16651133400000 > > > I can easily reproduce this. I can't reproduce on my meager dual core notebook. > > The repro gives me a task hanged at: > > # cat /proc/7563/task/*/stack > [<0>] fuse_wait_aborted+0x20b/0x320 > [<0>] fuse_sb_destroy+0xe2/0x1d0 > [<0>] fuse_kill_sb_anon+0x15/0x20 > [<0>] deactivate_locked_super+0x97/0x100 > [<0>] deactivate_super+0x2bb/0x320 > [<0>] cleanup_mnt+0xbf/0x160 > [<0>] __cleanup_mnt+0x16/0x20 > [<0>] task_work_run+0x1e8/0x2a0 > [<0>] exit_to_usermode_loop+0x318/0x380 > [<0>] do_syscall_64+0x6be/0x820 > [<0>] entry_SYSCALL_64_after_hwframe+0x49/0xbe > [<0>] 0xffffffffffffffff > > I double checked that writing to /sys/fs/fuse/connections/44/abort did > not help (the only entry in fuse/connections). Wrote multiple times, > and tried to kill the task, nothing helps. What's the output of cat /sys/fs/fuse/connections/NN/waiting ? Thanks, Miklos