From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f69.google.com (mail-oo1-f69.google.com [209.85.161.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CD048175A6A for ; Sun, 1 Mar 2026 18:35:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.69 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772390129; cv=none; b=RTdY1AFMoVq6l/u/1N6amZO74c5chJ3uI02r5xrJERsvHfVfIgNGphS/HSRyuAmiv/dP1ye/hjEyFW5rn8wi6uqRILFgn5cskwaqEgK3z6esEtDsdB+OhqgOsfS+oS/laQu57lRaoOEtv6Uw3Mhz3cd97I/LEQ13VrlVHTk5n9c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772390129; c=relaxed/simple; bh=Sx2qiZCmvyZr1+x0tQ30Z1GMVAY2u8hJ+Oun+qEC7oQ=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=AA7U1JqUQtRz/ON08TTMVlSVhxIZGHBT7ldrxUp9ZAaI+4zW8/xH4xpwHLPifC8d1gJak8JcPZm0DGgCLrstcaF4Eo+J1y3x9C5E5URfuFyUPjGZgPjvfd+80g2WvmXqAiIcMGix45lyA7SY7j0YVODgeEQy3dNHQpvVGMdUu9A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.161.69 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oo1-f69.google.com with SMTP id 006d021491bc7-679c6ef1538so78153370eaf.3 for ; Sun, 01 Mar 2026 10:35:27 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1772390127; x=1772994927; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=G1UYv/jtRxH/t46qvbmQtlpVvuiG18i64ydB7qEvuG8=; b=Pi6ecfZGb54q7Sh8hDqrutW8SF/0bByvvyWZF3l8g2iCtA+zitJl0ZfeLwILuBZQiz yF2r+nuu50JLPBlSTEzufaBEdpX1bWKkrDdzk8+piCU3FOs40WEX1ECAf/HLQQhBLMW7 g1Ua2BjYSFhO3FMSUQawtLBkIDVXP/m2bs9hfpA9M4O1fNJtopgYdTfsaUMOmpuMQPS/ thfgY2FRj2S9bxmloxD+vjEL9INFIYNeBZ51I6GD4+2N+NyMt4Tsv+VXYkQ18A1wCelB H+wkq5E/LJBFeLGzA5dKkcFEegnrDMIH5jOfysYDWjuk1wJhve5YJMhTlBh12zZCuDyi pTIQ== X-Forwarded-Encrypted: i=1; AJvYcCVq3lHQIYVa4vzuwZaadiawdZN6O4NVqVvtzGVUivwpCWmqeIE8JJoYPNF1JxKhwDzwf+O5C4k=@vger.kernel.org X-Gm-Message-State: AOJu0YzoqOJYnS/fJYMI/YzdZzuTeC5cFtIWXgUksKnfsqDv/9EKZXY6 DarefMsyK2i13x8UH4bVWrmG5cHlFxIKW3jZT+y9qiLDpeIte35SAkea5n5A5l9CHSCNFIJmSbA /NbMU5pGuTW8BhmuhwBpgK1A3mf/6X0hpC4hxiNelNmsv3k2ue9iGP3L9oec= Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:2503:b0:67a:422:d24 with SMTP id 006d021491bc7-67a04221235mr2401092eaf.70.1772390126842; Sun, 01 Mar 2026 10:35:26 -0800 (PST) Date: Sun, 01 Mar 2026 10:35:26 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69a486ee.050a0220.3a55be.0067.GAE@google.com> Subject: [syzbot] [kernel?] INFO: task hung in ret_from_fork (4) From: syzbot To: bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@redhat.com, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, tglx@kernel.org, x86@kernel.org Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 2f61f38a2174 net: stmmac: fix timestamping configuration a.. git tree: net console output: https://syzkaller.appspot.com/x/log.txt?x=16824d5a580000 kernel config: https://syzkaller.appspot.com/x/.config?x=665cbf0979cda6c5 dashboard link: https://syzkaller.appspot.com/bug?extid=7c11975a7e4a2735d529 compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10e9955a580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16b928d6580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/f3c4b4ab812f/disk-2f61f38a.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/a662c736eab0/vmlinux-2f61f38a.xz kernel image: https://storage.googleapis.com/syzbot-assets/345dc74120a7/bzImage-2f61f38a.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+7c11975a7e4a2735d529@syzkaller.appspotmail.com INFO: task kworker/1:8:5970 blocked for more than 159 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:8 state:D stack:30744 pid:5970 tgid:5970 ppid:2 task_flags:0x4208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 kthread+0x260/0x470 kernel/kthread.c:451 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 2 locks held by kworker/0:0/9: 1 lock held by kworker/0:1/10: #0: ffffffff8e5fec68 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2691 2 locks held by kworker/u8:0/12: 2 locks held by kworker/u8:1/13: 1 lock held by kworker/R-mm_pe/14: #0: ffffffff8e5fec68 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2749 [inline] #0: ffffffff8e5fec68 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0xc4a/0x1120 kernel/workqueue.c:3610 3 locks held by kworker/1:0/24: #0: ffff88813fe0f548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88813fe0f548 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc900001e7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc900001e7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 #2: ffff88807c222240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x202/0x3d0 drivers/net/netdevsim/fib.c:1490 1 lock held by khungtaskd/30: #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 8 locks held by kworker/u8:2/35: 3 locks held by kworker/1:1/42: 3 locks held by kworker/u8:3/49: #0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc90000b97c40 ((work_completion)(&pool->idle_cull_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc90000b97c40 ((work_completion)(&pool->idle_cull_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 #2: ffffffff8e5fec68 (wq_pool_attach_mutex){+.+.}-{4:4}, at: idle_cull_fn+0xd2/0x740 kernel/workqueue.c:2973 2 locks held by kworker/u8:4/77: 3 locks held by kworker/u8:5/86: #0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc900025dfc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc900025dfc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 #2: ffffffff8fbcb888 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313 2 locks held by kworker/u8:6/146: 2 locks held by kworker/0:2/796: 2 locks held by kworker/u8:7/1116: 1 lock held by kworker/u8:8/1147: #0: ffffffff8e5fec68 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2691 2 locks held by kworker/u8:9/1168: 1 lock held by kworker/1:2/1997: #0: ffffffff8e5fec68 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x2e/0x3a0 kernel/workqueue.c:2691 3 locks held by kworker/u8:10/2990: 2 locks held by getty/5581: #0: ffff888036c110a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:3/5810: 2 locks held by syz-executor210/5855: #0: ffffffff8fbcb888 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8fbcb888 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8fbcb888 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071 #1: ffff88806d1a5528 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_open+0x227/0x420 drivers/net/wireguard/device.c:50 1 lock held by syz-executor210/5856: #0: ffffffff8fbcb888 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8fbcb888 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x722/0xbe0 net/core/rtnetlink.c:6964 3 locks held by kworker/1:4/5865: 7 locks held by kworker/u9:3/5869: #0: ffff88807a26f948 ((wq_completion)hci2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88807a26f948 ((wq_completion)hci2){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc90003ba7c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc90003ba7c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 #2: ffff888076408ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331 #3: ffff8880764080c0 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0xa6f/0x1190 net/bluetooth/hci_sync.c:5734 #4: ffffffff8fd57f28 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2136 [inline] #4: ffffffff8fd57f28 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x165/0x340 net/bluetooth/hci_conn.c:1342 #5: ffff888057b3caf8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 net/bluetooth/l2cap_core.c:1755 #6: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #6: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 5 locks held by kworker/u9:4/5870: #0: ffff88807c3fa148 ((wq_completion)hci4){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88807c3fa148 ((wq_completion)hci4){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 --- This report is generated by a bot. 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