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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 374C6C433F5 for ; Thu, 2 Dec 2021 09:08:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345898AbhLBJLx (ORCPT ); Thu, 2 Dec 2021 04:11:53 -0500 Received: from mail-io1-f71.google.com ([209.85.166.71]:45664 "EHLO mail-io1-f71.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345884AbhLBJLs (ORCPT ); Thu, 2 Dec 2021 04:11:48 -0500 Received: by mail-io1-f71.google.com with SMTP id ay10-20020a5d9d8a000000b005e238eaeaa9so32091152iob.12 for ; Thu, 02 Dec 2021 01:08:24 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=2nEPO550Rj0CJg8yzFP5f3pa89cCWBV9CiKJJK9J9Ac=; b=A+f9Jm7BreWIcsblEjFywk1Jrnjes68P9yQIkCSZwsL6vD/OYHXAgg3ColsAB3hFc4 iSm9FeaZTen1zs5k7+xcQXRm/zCm8Rk2RQUn/oYPhDJ5g/4ICoyrVgkfPlrlI8+SG+E9 rJwhtfctnYw51dQ33ez2xKB7qHiQqCeT8Eehg1sAl9QiWoeDjG8gDocP83FzH1p8FX+4 CV9mSgt6CdfMZXneDR9oPX++ZMNPX237toWFuPAm0QbE1kAF8yWmkfhJRyE2qGzWFLyf KmzLVk7dO5ISVpzdqQN3+0KeRn0pG+/Oahp99u1Isl4jaq2zVHORYREUg3rSZoAK2GzP gdIQ== X-Gm-Message-State: AOAM531DpIPCsjBlTI1XDWDsLHToFNuTTdlh78JGmgoUVsUgAn1EwsBL pNyxPRgx0l0E0vAsmafgwGpxCh030fJmEayOd+8nNHZ35cFw X-Google-Smtp-Source: ABdhPJwdIiqglfIfrBETAzYIY+rhwwS3wQVLPY4aL7a9eQGw6Sh6Athe+nzFhQbvf66S+B/MJoucChJZb6IAY85eDyrQWXmZKz/U MIME-Version: 1.0 X-Received: by 2002:a6b:b2c1:: with SMTP id b184mr14946846iof.24.1638436103738; Thu, 02 Dec 2021 01:08:23 -0800 (PST) Date: Thu, 02 Dec 2021 01:08:23 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000f35e3b05d22621ff@google.com> Subject: [syzbot] INFO: task hung in io_uring_try_cancel_iowq 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: 58e1100fdc59 MAINTAINERS: co-maintain random.c git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=14b06cc5b00000 kernel config: https://syzkaller.appspot.com/x/.config?x=e9ea28d2c3c2c389 dashboard link: https://syzkaller.appspot.com/bug?extid=97bcaa1dfa37e2512746 compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+97bcaa1dfa37e2512746@syzkaller.appspotmail.com INFO: task kworker/u4:10:22176 blocked for more than 143 seconds. Not tainted 5.16.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:10 state:D stack:22352 pid:22176 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xb72/0x1460 kernel/sched/core.c:6253 schedule+0x12b/0x1f0 kernel/sched/core.c:6326 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6385 __mutex_lock_common+0xd1f/0x2590 kernel/locking/mutex.c:680 __mutex_lock kernel/locking/mutex.c:740 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:792 io_uring_try_cancel_iowq+0x2e/0x17e fs/io_uring.c:9644 io_uring_try_cancel_requests+0x16f/0x42a fs/io_uring.c:9674 io_ring_exit_work+0x10b/0x6b7 fs/io_uring.c:9483 process_one_work+0x853/0x1140 kernel/workqueue.c:2298 worker_thread+0xac1/0x1320 kernel/workqueue.c:2445 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8cb1db40 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by in:imklog/6218: #0: ffff88801a8a9c70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 fs/file.c:990 3 locks held by kworker/u4:10/22176: #0: ffff888011469138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc9000f5a7d20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2273 #2: ffff88807ca0c0a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_iowq+0x2e/0x17e fs/io_uring.c:9644 2 locks held by kworker/u4:7/4146: 3 locks held by iou-sqp-5421/5424: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.16.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x16a/0x280 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+0xc82/0xcd0 kernel/hung_task.c:295 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 2950 Comm: systemd-journal Not tainted 5.16.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_kcov_mode kernel/kcov.c:177 [inline] RIP: 0010:write_comp_data kernel/kcov.c:221 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x31/0xa0 kernel/kcov.c:287 Code: 14 25 c0 6f 02 00 65 8b 05 74 e3 7d 7e a9 00 01 ff 00 74 10 a9 00 01 00 00 74 6e 83 ba a4 15 00 00 00 74 65 8b 82 80 15 00 00 <83> f8 03 75 5a 48 8b 8a 88 15 00 00 44 8b 8a 84 15 00 00 49 c1 e1 RSP: 0018:ffffc90001acf6d0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc90001acfbc0 RCX: ffff88807d1bba00 RDX: ffff88807d1bba00 RSI: 0000000000000040 RDI: 0000000000000000 RBP: 0000000000000051 R08: ffffffff81df889b R09: ffffc90001acf660 R10: fffff52000359ed5 R11: 0000000000000000 R12: 1ffff92000359f7f R13: dffffc0000000000 R14: ffffc90001acfbf8 R15: dffffc0000000000 FS: 00007f46c1ca58c0(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f46bf1cd000 CR3: 000000001f549000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: try_to_unlazy+0x7b/0xce0 fs/namei.c:772 may_lookup fs/namei.c:1684 [inline] link_path_walk+0x298/0xd00 fs/namei.c:2239 path_openat+0x25b/0x3660 fs/namei.c:3555 do_filp_open+0x277/0x4f0 fs/namei.c:3586 do_sys_openat2+0x13b/0x500 fs/open.c:1212 do_sys_open fs/open.c:1228 [inline] __do_sys_open fs/open.c:1236 [inline] __se_sys_open fs/open.c:1232 [inline] __x64_sys_open+0x221/0x270 fs/open.c:1232 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f46c1234840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007fffe2dca4d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007fffe2dca7e0 RCX: 00007f46c1234840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 0000563b4c24d640 RBP: 000000000000000d R08: 000000000000c0c1 R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000563b4c240040 R14: 00007fffe2dca7a0 R15: 0000563b4c24d690 ---------------- Code disassembly (best guess): 0: 14 25 adc $0x25,%al 2: c0 6f 02 00 shrb $0x0,0x2(%rdi) 6: 65 8b 05 74 e3 7d 7e mov %gs:0x7e7de374(%rip),%eax # 0x7e7de381 d: a9 00 01 ff 00 test $0xff0100,%eax 12: 74 10 je 0x24 14: a9 00 01 00 00 test $0x100,%eax 19: 74 6e je 0x89 1b: 83 ba a4 15 00 00 00 cmpl $0x0,0x15a4(%rdx) 22: 74 65 je 0x89 24: 8b 82 80 15 00 00 mov 0x1580(%rdx),%eax * 2a: 83 f8 03 cmp $0x3,%eax <-- trapping instruction 2d: 75 5a jne 0x89 2f: 48 8b 8a 88 15 00 00 mov 0x1588(%rdx),%rcx 36: 44 8b 8a 84 15 00 00 mov 0x1584(%rdx),%r9d 3d: 49 rex.WB 3e: c1 .byte 0xc1 3f: e1 .byte 0xe1 --- This report is generated by a bot. 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