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=-3.7 required=3.0 tests=BAYES_00,FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 2D10BC433ED for ; Mon, 5 Apr 2021 09:16:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0454960FE4 for ; Mon, 5 Apr 2021 09:16:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240702AbhDEJQ2 (ORCPT ); Mon, 5 Apr 2021 05:16:28 -0400 Received: from mail-il1-f200.google.com ([209.85.166.200]:53554 "EHLO mail-il1-f200.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240664AbhDEJQ0 (ORCPT ); Mon, 5 Apr 2021 05:16:26 -0400 Received: by mail-il1-f200.google.com with SMTP id k12so9084884ilo.20 for ; Mon, 05 Apr 2021 02:16:19 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=KLYne9xufLsaxUu1sT+N6RlFETRtpqJnfrhYs9NCzgs=; b=d9POe4IL0Rk0n3WLN6csGM5r0yZYN3N7gRc15aOi1Q3Nn+VcdufpDvPreeTnc2oExb iDvIrKicE2CdKKIUOPge3pdLH4LvFa3phd9HCGj1JFyhbEHi/254zkqG3+8yuDufz0ji unrovQr1ZlhkTXgw3r9Hwpopr1XTc6FZOHWq4E2rhEmOSoFqAGezi0fqYK97FzkS5VOs aTgdU0RzRny5ETiMHU6+BCtR7X9U0NuiLKjN4yDAWK+g9/EcNDXzatlJ+f8er8OhBGBR u/rVidWC8MLlxR5w2K9FCVLbF7OZ43C1gaXuv1kynimZstjifKUACx3byjEqn25qA4dl yOhQ== X-Gm-Message-State: AOAM533atlXBB2+DA6EOVix273mSEMMolzzGRzUadme0kDYUx1VyZ05w DwAsifLAIBtQlhSdQSx/k9guVsfcI5WEg5q9sM3279/Hsm7v X-Google-Smtp-Source: ABdhPJzop5rQhtRShgAje33kGUShImMoOUwsHIySxxTMeowObTigRZ1FRDw1dplaTOp5+cxLNgua2bF2Z7YUJbBoTmuDs57ZxZwo MIME-Version: 1.0 X-Received: by 2002:a92:b70f:: with SMTP id k15mr19053650ili.68.1617614179329; Mon, 05 Apr 2021 02:16:19 -0700 (PDT) Date: Mon, 05 Apr 2021 02:16:19 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000008aed3505bf362671@google.com> Subject: [syzbot] INFO: task hung in io_ring_exit_work From: syzbot To: asml.silence@gmail.com, axboe@kernel.dk, io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: e49d033b Linux 5.12-rc6 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16217d16d00000 kernel config: https://syzkaller.appspot.com/x/.config?x=9320464bf47598bd dashboard link: https://syzkaller.appspot.com/bug?extid=93f72b3885406bb09e0d syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15741cfcd00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14c10a96d00000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+93f72b3885406bb09e0d@syzkaller.appspotmail.com INFO: task kworker/u4:6:3091 blocked for more than 143 seconds. Not tainted 5.12.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:6 state:D stack:24792 pid: 3091 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:4322 [inline] __schedule+0x911/0x21b0 kernel/sched/core.c:5073 schedule+0xcf/0x270 kernel/sched/core.c:5152 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1868 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+0x168/0x270 kernel/sched/completion.c:138 io_ring_exit_work+0x4e8/0x12d0 fs/io_uring.c:8596 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Showing all locks held in the system: 2 locks held by kworker/u4:5/235: #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc900019bfda8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 1 lock held by khungtaskd/1630: #0: ffffffff8bf74320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6327 2 locks held by kworker/u4:6/3091: #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc90001cbfda8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 1 lock held by in:imklog/8101: #0: ffff88801523b270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:961 2 locks held by kworker/u4:1/11499: #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc9000d957da8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 2 locks held by syz-executor633/15066: #0: ffff8880b9d35198 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1321 [inline] #0: ffff8880b9d35198 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x21c/0x21b0 kernel/sched/core.c:4990 #1: ffff8880b9d1f948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x305/0x440 kernel/sched/psi.c:833 1 lock held by syz-executor633/15068: #0: ffffffff8bf7cee8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #0: ffffffff8bf7cee8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4fa/0x620 kernel/rcu/tree_exp.h:836 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1630 Comm: khungtaskd Not tainted 5.12.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd48/0xfb0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 8393 Comm: syz-executor633 Not tainted 5.12.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:wait_consider_task+0x99/0x3b40 kernel/exit.c:1288 Code: 28 00 00 00 48 89 84 24 f0 00 00 00 31 c0 e8 ae 8e 2f 00 49 8d 8f ec 04 00 00 48 89 c8 48 89 4c 24 10 48 c1 e8 03 0f b6 14 28 <48> 89 c8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 4b 1d 00 00 45 RSP: 0018:ffffc9000146fb20 EFLAGS: 00000a07 RAX: 1ffff11015477b35 RBX: 0000000000000000 RCX: ffff8880aa3bd9ac RDX: 0000000000000000 RSI: ffffffff814462a2 RDI: ffffc9000146fd20 RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff8bc0a083 R10: ffffffff8144a0e2 R11: 0000000000000001 R12: ffffc9000146fd20 R13: ffff888020ff9c40 R14: 0000000000000000 R15: ffff8880aa3bd4c0 FS: 0000000001688300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f42f9b4c000 CR3: 0000000025681000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: do_wait_thread kernel/exit.c:1397 [inline] do_wait+0x376/0xa00 kernel/exit.c:1468 kernel_wait4+0x14c/0x260 kernel/exit.c:1630 __do_sys_wait4+0x13f/0x150 kernel/exit.c:1658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x444d06 Code: 0f 1f 40 00 31 c9 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 49 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 90 48 83 ec 28 89 54 24 14 48 89 74 24 RSP: 002b:00007ffe758f7cb8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d RAX: ffffffffffffffda RBX: 00000000000d35a7 RCX: 0000000000444d06 RDX: 0000000040000001 RSI: 00007ffe758f7ce4 RDI: 00000000ffffffff RBP: 00000000000019f2 R08: 0000000000000000 R09: 00007ffe75923090 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe758f7ce4 R13: 00007ffe758f7d40 R14: 000000000000028f R15: 00007ffe758f7d20 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches