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=-6.2 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,NICE_REPLY_A,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 52F4FC433EF for ; Wed, 8 Sep 2021 20:16:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3378C6115B for ; Wed, 8 Sep 2021 20:16:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345241AbhIHUR4 (ORCPT ); Wed, 8 Sep 2021 16:17:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54682 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233179AbhIHUR4 (ORCPT ); Wed, 8 Sep 2021 16:17:56 -0400 Received: from mail-wm1-x329.google.com (mail-wm1-x329.google.com [IPv6:2a00:1450:4864:20::329]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 909D2C061575; Wed, 8 Sep 2021 13:16:47 -0700 (PDT) Received: by mail-wm1-x329.google.com with SMTP id y132so2672696wmc.1; Wed, 08 Sep 2021 13:16:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=CsCxlyyBkM+9pVONuUKttThrrFrN/a6bSIPojN51siw=; b=OTO0lT6m8/JbKRKOStnBt8XJN+Ox4swhLkK58fvACLhdYXLKpBdgnS+xVJR9f9LgGN PUgKkT75Eb+9WXjAB4YW23fGWwYRjBrJl/4wrJBR3ZOUhbAkjKzFnXw3EZ5TuFOGbv8H R6Y5tJNJqNIjcvZ5BjJ1e2oK04qHcWHb+04YOGugcbVNg6XJAjDpSeh4j2obUhnN2LTy 6aZ1VjzH9XFzrIQUwqNxM0tALcXaWeHv+7Sg1IO7jEmdfxZPLeSQQsdAMAa939nTaOLF smYx41ffAE1DEnHBbeyg1zSz7xx7ofNrqvDK4s0WCtpflSKqAgWluJ0RNft559QXuCIA QphQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=CsCxlyyBkM+9pVONuUKttThrrFrN/a6bSIPojN51siw=; b=AMho7mOTsZ71OGKSuA5roBetlverJrBu4eReMTYk4EuzOzaANmjLtYwAIJstymrTk5 AeaByhgwhxThcVD3rE+C9aIIIzjc8OKX40xr+HCyhZK6FqGKrAo75Wcl45/agzxU6LQG NztTWbsmr7faXYhj2X74j+uT79AUoin2OyvrxJ5FX7hMYNRHYy9UnFQFzqLVs4H8YjRJ vaUBbEERbpkv6Yot14fXHwBsYeRJMstwU+DyLUUhlFgN6gKFN3+eZxIJsCe0WGS8y8JP 9JtyAYKdKrR/IWp3AoaM215lPZCpYLvDL0b8CHPfBDXC1kuhIQauIHP4QYF6io51K4ts +3mw== X-Gm-Message-State: AOAM5326hPX808LuSTEEUerM51XNSarBGLr+ah3HiQEl5DHWLDaWQTA3 df6aEEIKKbHdsUKB/JfAg9vCUSRZhyQ= X-Google-Smtp-Source: ABdhPJw1xq4JqF7AWky052AUlwTzHKDWLX5kmfQoJ6eapKcQfcRmhYy8dwdbEyxVitGaAGw8Cx8iOw== X-Received: by 2002:a05:600c:2245:: with SMTP id a5mr5384701wmm.19.1631132205680; Wed, 08 Sep 2021 13:16:45 -0700 (PDT) Received: from [192.168.8.197] ([185.69.144.232]) by smtp.gmail.com with ESMTPSA id l10sm151117wrg.50.2021.09.08.13.16.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 08 Sep 2021 13:16:45 -0700 (PDT) Subject: Re: INFO: task hung in io_uring_cancel_generic To: Hao Sun Cc: Jens Axboe , io-uring@vger.kernel.org, linux-kernel@vger.kernel.org References: From: Pavel Begunkov Message-ID: Date: Wed, 8 Sep 2021 21:16:12 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 9/8/21 7:57 AM, Hao Sun wrote: > Another similar report: INFO: task hung in io_ring_exit_work > > INFO: task kworker/u9:3:1867 blocked for more than 143 seconds. > Not tainted 5.14.0+ #13 > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > task:kworker/u9:3 state:D stack:12344 pid: 1867 ppid: 2 flags:0x00004000 > Workqueue: events_unbound io_ring_exit_work This one is different. I guess it may be difficult for syz to find a repro because of the delay before the warning appears. How about to reduce it to a lower value? like 2-5 seconds echo 5 > /proc/sys/kernel/hung_task_timeout_secs > Call Trace: > context_switch kernel/sched/core.c:4940 [inline] > __schedule+0x323/0xae0 kernel/sched/core.c:6287 > schedule+0x36/0xe0 kernel/sched/core.c:6366 > schedule_timeout+0x189/0x430 kernel/time/timer.c:1857 > do_wait_for_common kernel/sched/completion.c:85 [inline] > __wait_for_common kernel/sched/completion.c:106 [inline] > wait_for_common kernel/sched/completion.c:117 [inline] > wait_for_completion+0xb4/0x110 kernel/sched/completion.c:138 > io_ring_exit_work+0x287/0x850 fs/io_uring.c:9297 > process_one_work+0x359/0x850 kernel/workqueue.c:2297 > worker_thread+0x41/0x4d0 kernel/workqueue.c:2444 > kthread+0x178/0x1b0 kernel/kthread.c:319 > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 > INFO: task kworker/u9:4:2050 blocked for more than 143 seconds. > Not tainted 5.14.0+ #13 > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > task:kworker/u9:4 state:D stack:12232 pid: 2050 ppid: 2 flags:0x00004000 > Workqueue: events_unbound io_ring_exit_work > Call Trace: > context_switch kernel/sched/core.c:4940 [inline] > __schedule+0x323/0xae0 kernel/sched/core.c:6287 > schedule+0x36/0xe0 kernel/sched/core.c:6366 > schedule_timeout+0x189/0x430 kernel/time/timer.c:1857 > do_wait_for_common kernel/sched/completion.c:85 [inline] > __wait_for_common kernel/sched/completion.c:106 [inline] > wait_for_common kernel/sched/completion.c:117 [inline] > wait_for_completion+0xb4/0x110 kernel/sched/completion.c:138 > io_ring_exit_work+0x287/0x850 fs/io_uring.c:9297 > process_one_work+0x359/0x850 kernel/workqueue.c:2297 > worker_thread+0x41/0x4d0 kernel/workqueue.c:2444 > kthread+0x178/0x1b0 kernel/kthread.c:319 > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 > > Showing all locks held in the system: > 1 lock held by khungtaskd/1340: > #0: ffffffff85a1d3a0 (rcu_read_lock){....}-{1:2}, at: > debug_show_all_locks+0xe/0x1a0 kernel/locking/lockdep.c:6446 > 2 locks held by kworker/u9:3/1867: > #0: ffff888008c5c938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: > set_work_data kernel/workqueue.c:633 [inline] > #0: ffff888008c5c938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: > set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] > #0: ffff888008c5c938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: > process_one_work+0x2a0/0x850 kernel/workqueue.c:2268 > #1: ffffc90003e67e70 > ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: set_work_data > kernel/workqueue.c:633 [inline] > #1: ffffc90003e67e70 > ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: > set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] > #1: ffffc90003e67e70 > ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: > process_one_work+0x2a0/0x850 kernel/workqueue.c:2268 > 2 locks held by kworker/u9:4/2050: > #0: ffff888008c5c938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: > set_work_data kernel/workqueue.c:633 [inline] > #0: ffff888008c5c938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: > set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] > #0: ffff888008c5c938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: > process_one_work+0x2a0/0x850 kernel/workqueue.c:2268 > #1: ffffc90004327e70 > ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: set_work_data > kernel/workqueue.c:633 [inline] > #1: ffffc90004327e70 > ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: > set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] > #1: ffffc90004327e70 > ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: > process_one_work+0x2a0/0x850 kernel/workqueue.c:2268 > 1 lock held by in:imklog/8089: > #0: ffff88800ece7ef0 (&f->f_pos_lock){+.+.}-{3:3}, at: > __fdget_pos+0x55/0x60 fs/file.c:990 > > ============================================= > > NMI backtrace for cpu 0 > CPU: 0 PID: 1340 Comm: khungtaskd Not tainted 5.14.0+ #13 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 > Call Trace: > __dump_stack lib/dump_stack.c:88 [inline] > dump_stack_lvl+0x8d/0xcf lib/dump_stack.c:105 > nmi_cpu_backtrace+0x1e9/0x210 lib/nmi_backtrace.c:105 > nmi_trigger_cpumask_backtrace+0x120/0x180 lib/nmi_backtrace.c:62 > trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] > check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] > watchdog+0x4e1/0x980 kernel/hung_task.c:295 > kthread+0x178/0x1b0 kernel/kthread.c:319 > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 > Sending NMI from CPU 0 to CPUs 1-3: > NMI backtrace for cpu 1 > CPU: 1 PID: 4934 Comm: systemd-journal Not tainted 5.14.0+ #13 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 > RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:91 [inline] > RIP: 0010:lock_acquire+0x1a4/0x340 kernel/locking/lockdep.c:5601 > Code: 04 25 28 00 00 00 0f 85 b5 01 00 00 48 83 c4 38 5b 5d 41 5c 41 > 5d 41 5e 41 5f c3 65 48 8b 04 25 40 70 01 00 8b 80 f4 09 00 00 <85> c0 > 0f 85 c5 fe ff ff 9c 8f 04 24 fa 48 c7 c7 a0 36 5d 85 e8 e3 > RSP: 0018:ffffc9000086fe18 EFLAGS: 00000246 > RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 > RDX: 0000000000000001 RSI: ffffffff852a8b94 RDI: ffffffff853cae8e > RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff85a1d3a0 > R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000000 > FS: 00007f940a97b8c0(0000) GS:ffff88813dc00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007f9407aa3000 CR3: 000000000f49a000 CR4: 0000000000750ee0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > PKRU: 55555554 > Call Trace: > rcu_lock_acquire include/linux/rcupdate.h:267 [inline] > rcu_read_lock include/linux/rcupdate.h:687 [inline] > dput+0x72/0x650 fs/dcache.c:874 > path_put+0x12/0x20 fs/namei.c:557 > do_faccessat+0x1fa/0x370 fs/open.c:455 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x34/0xb0 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae > RIP: 0033:0x7f9409c379c7 > Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 > 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d > 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48 > RSP: 002b:00007ffeead2d338 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 > RAX: ffffffffffffffda RBX: 00007ffeead30250 RCX: 00007f9409c379c7 > RDX: 00007f940a6a8a00 RSI: 0000000000000000 RDI: 000055d9e89aa9a3 > RBP: 00007ffeead2d370 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 > R13: 0000000000000000 R14: 00007ffeead30250 R15: 00007ffeead2d860 > NMI backtrace for cpu 2 skipped: idling at native_safe_halt > arch/x86/include/asm/irqflags.h:51 [inline] > NMI backtrace for cpu 2 skipped: idling at arch_safe_halt > arch/x86/include/asm/irqflags.h:89 [inline] > NMI backtrace for cpu 2 skipped: idling at default_idle+0xb/0x10 > arch/x86/kernel/process.c:716 > NMI backtrace for cpu 3 > CPU: 3 PID: 8091 Comm: rs:main Q:Reg Not tainted 5.14.0+ #13 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 > RIP: 0010:memset_erms+0x9/0x10 arch/x86/lib/memset_64.S:64 > Code: c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 > f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 aa > 4c 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 > RSP: 0018:ffffc90007a23ba8 EFLAGS: 00010216 > RAX: 0000000000000000 RBX: ffff88810cd3ec78 RCX: 0000000000000c85 > RDX: 0000000000000d05 RSI: 0000000000000000 RDI: ffff888107f7b37b > RBP: 0000000000001000 R08: 0000000000000000 R09: ffff888107f7b2fb > R10: ffffc90007a23978 R11: 0000000000000005 R12: 0000000000000000 > R13: 0000000000000000 R14: 0000000000001000 R15: ffffea00041fdec0 > FS: 00007fd86dba4700(0000) GS:ffff88813dd00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 000055d6e0599858 CR3: 0000000012b38000 CR4: 0000000000750ee0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > PKRU: 55555554 > Call Trace: > memset include/linux/fortify-string.h:175 [inline] > zero_user_segments include/linux/highmem.h:211 [inline] > ext4_block_write_begin+0x63e/0x980 fs/ext4/inode.c:1089 > ext4_da_write_begin+0x275/0x610 fs/ext4/inode.c:3021 > generic_perform_write+0xce/0x220 mm/filemap.c:3770 > ext4_buffered_write_iter+0xd6/0x190 fs/ext4/file.c:269 > ext4_file_write_iter+0x80/0x940 fs/ext4/file.c:680 > call_write_iter include/linux/fs.h:2163 [inline] > new_sync_write+0x18d/0x260 fs/read_write.c:507 > vfs_write+0x43b/0x4a0 fs/read_write.c:594 > ksys_write+0xd2/0x120 fs/read_write.c:647 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x34/0xb0 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae > RIP: 0033:0x7fd8705e81cd > Code: c2 20 00 00 75 10 b8 01 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 > c3 48 83 ec 08 e8 ae fc ff ff 48 89 04 24 b8 01 00 00 00 0f 05 <48> 8b > 3c 24 48 89 c2 e8 f7 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 > RSP: 002b:00007fd86dba3590 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 > RAX: ffffffffffffffda RBX: 00007fd8640268f0 RCX: 00007fd8705e81cd > RDX: 00000000000004ce RSI: 00007fd8640268f0 RDI: 0000000000000008 > RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000293 R12: 00007fd864026670 > R13: 00007fd86dba35b0 R14: 00005563e5cf4440 R15: 00000000000004ce > ---------------- > Code disassembly (best guess): > 0: 04 25 add $0x25,%al > 2: 28 00 sub %al,(%rax) > 4: 00 00 add %al,(%rax) > 6: 0f 85 b5 01 00 00 jne 0x1c1 > c: 48 83 c4 38 add $0x38,%rsp > 10: 5b pop %rbx > 11: 5d pop %rbp > 12: 41 5c pop %r12 > 14: 41 5d pop %r13 > 16: 41 5e pop %r14 > 18: 41 5f pop %r15 > 1a: c3 retq > 1b: 65 48 8b 04 25 40 70 mov %gs:0x17040,%rax > 22: 01 00 > 24: 8b 80 f4 09 00 00 mov 0x9f4(%rax),%eax > * 2a: 85 c0 test %eax,%eax <-- trapping instruction > 2c: 0f 85 c5 fe ff ff jne 0xfffffef7 > 32: 9c pushfq > 33: 8f 04 24 popq (%rsp) > 36: fa cli > 37: 48 c7 c7 a0 36 5d 85 mov $0xffffffff855d36a0,%rdi > 3e: e8 .byte 0xe8 > 3f: e3 .byte 0xe3% > > Hao Sun 于2021年9月8日周三 上午9:01写道： >> >> Pavel Begunkov 于2021年9月8日周三 上午5:31写道： >>> >>> On 9/7/21 8:30 PM, Jens Axboe wrote: >>>> On 9/7/21 5:50 AM, Hao Sun wrote: >>>>> Hello, >>>>> >>>>> When using Healer to fuzz the latest Linux kernel, the following crash >>>>> was triggered. >>>>> >>>>> HEAD commit: 7d2a07b76933 Linux 5.14 >>>>> git tree: upstream >>>>> console output: >>>>> https://drive.google.com/file/d/1c8uRooM0TwJiTIwEviOCB4RC-hhOgGHR/view?usp=sharing >>>>> kernel config: https://drive.google.com/file/d/1XD9WYDViQLSXN7RGwH8AGGDvP9JvOghx/view?usp=sharing >>>>> Similar report: >>>>> https://groups.google.com/u/1/g/syzkaller-bugs/c/FvdcTiJIGtY/m/PcXkoenUAAAJ >>>>> >>>>> Sorry, I don't have a reproducer for this crash, hope the symbolized >>>>> report can help. >>>>> If you fix this issue, please add the following tag to the commit: >>>>> Reported-by: Hao Sun >>>> >>>> Would be great with a reproducer for this one, though... >>> >>> And syzbot usually sends an execution log with all syz programs >>> it run, which may be helpful. Any chance you have anything similar >>> left? >>> >> >> Yes, found it[1]. Here is an execution history with latest 1024 >> executed progs before crash saved. >> Hope it can help. I'll also follow this crash closely, see if Healer >> can find a reproducer and send it to you once it found. >> >> [1] https://drive.google.com/file/d/14k8qOFeyKPD4HsqOpIjud3b9jsxFSo-u/view?usp=sharing >> >>> -- >>> Pavel Begunkov -- Pavel Begunkov