INFO: task kworker/0:3:5047 blocked for more than 143 seconds. Not tainted 6.8.0-rc1-syzkaller-00311-g3a5879d495b2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:3 state:D stack:19832 pid:5047 tgid:5047 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x177f/0x4960 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6874 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a3/0xd60 kernel/locking/mutex.c:752 hub_port_connect drivers/usb/core/hub.c:5363 [inline] hub_port_connect_change drivers/usb/core/hub.c:5605 [inline] port_event drivers/usb/core/hub.c:5765 [inline] hub_event+0x2682/0x5050 drivers/usb/core/hub.c:5847 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x90f/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d92ef20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8d92ef20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8d92ef20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 5 locks held by kworker/1:2/924: #0: ffff888019ad5538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888019ad5538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc900044bfd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc900044bfd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffff888022aba190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:990 [inline] #2: ffff888022aba190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x5050 drivers/usb/core/hub.c:5793 #3: ffff888022abe510 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3151 [inline] #3: ffff888022abe510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5362 [inline] #3: ffff888022abe510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5605 [inline] #3: ffff888022abe510 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5765 [inline] #3: ffff888022abe510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x264e/0x5050 drivers/usb/core/hub.c:5847 #4: ffff888021af3e38 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5363 [inline] #4: ffff888021af3e38 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5605 [inline] #4: ffff888021af3e38 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5765 [inline] #4: ffff888021af3e38 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x2682/0x5050 drivers/usb/core/hub.c:5847 2 locks held by getty/4801: #0: ffff8880298e30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002efe2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 5 locks held by kworker/0:3/5047: #0: ffff888019ad5538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888019ad5538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc90003af7d20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc90003af7d20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffff888022b22190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:990 [inline] #2: ffff888022b22190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x5050 drivers/usb/core/hub.c:5793 #3: ffff888022b25510 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3151 [inline] #3: ffff888022b25510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5362 [inline] #3: ffff888022b25510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5605 [inline] #3: ffff888022b25510 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5765 [inline] #3: ffff888022b25510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x264e/0x5050 drivers/usb/core/hub.c:5847 #4: ffff888021af3e38 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5363 [inline] #4: ffff888021af3e38 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5605 [inline] #4: ffff888021af3e38 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5765 [inline] #4: ffff888021af3e38 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x2682/0x5050 drivers/usb/core/hub.c:5847 1 lock held by syz-executor.4/5093: #0: ffffffff8d9348b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #0: ffffffff8d9348b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x46c/0x890 kernel/rcu/tree_exp.h:995 5 locks held by kworker/0:6/5142: #0: ffff888019ad5538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888019ad5538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc9000464fd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc9000464fd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffff888022d03190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:990 [inline] #2: ffff888022d03190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x5050 drivers/usb/core/hub.c:5793 #3: ffff888022d06510 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3151 [inline] #3: ffff888022d06510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5362 [inline] #3: ffff888022d06510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5605 [inline] #3: ffff888022d06510 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5765 [inline] #3: ffff888022d06510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x264e/0x5050 drivers/usb/core/hub.c:5847 #4: ffff888022ccf7d8 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5363 [inline] #4: ffff888022ccf7d8 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5605 [inline] #4: ffff888022ccf7d8 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5765 [inline] #4: ffff888022ccf7d8 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x2682/0x5050 drivers/usb/core/hub.c:5847 2 locks held by kworker/u4:7/22317: #0: ffff888013089938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888013089938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc90004aefd20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc90004aefd20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 2 locks held by kworker/u4:15/22331: #0: ffff888013089938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888013089938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc90004a7fd20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc90004a7fd20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 2 locks held by kworker/u4:16/22333: #0: ffff888013089938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888013089938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc90004bafd20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc90004bafd20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 4 locks held by kvm-nx-lpage-re/22564: #0: ffffffff8d959148 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:368 [inline] #0: ffffffff8d959148 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_attach_task_all+0x27/0xe0 kernel/cgroup/cgroup-v1.c:61 #1: ffffffff8d7ca9f0 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock+0x11/0x30 kernel/cgroup/cgroup.c:2413 #2: ffffffff8d959330 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_task_all+0x31/0xe0 kernel/cgroup/cgroup-v1.c:62 #3: ffffffff8d9348b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline] #3: ffffffff8d9348b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a3/0x890 kernel/rcu/tree_exp.h:995 1 lock held by syz-executor.0/22618: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc1-syzkaller-00311-g3a5879d495b2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x498/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x310 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfaf/0xff0 kernel/hung_task.c:379 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4504 Comm: udevd Not tainted 6.8.0-rc1-syzkaller-00311-g3a5879d495b2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 RIP: 0010:__lock_acquire+0x2e5/0x1fd0 kernel/locking/lockdep.c:5070 Code: 48 8b 44 24 50 4c 8d 80 c0 0a 00 00 83 fa 31 4c 89 44 24 08 0f 83 9b 19 00 00 4c 8d 34 92 4b 8d 5c f0 20 48 89 d8 48 c1 e8 03 <48> 89 44 24 20 0f b6 04 30 84 c0 0f 85 2a 14 00 00 48 8b ac 24 d0 RSP: 0018:ffffc90003157330 EFLAGS: 00000802 RAX: 1ffff1100f5a4519 RBX: ffff88807ad228c8 RCX: ffffffff925f1303 RDX: 0000000000000001 RSI: dffffc0000000000 RDI: 0000000000000083 RBP: 1ffff1100f5a4514 R08: ffff88807ad22880 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1e04796 R12: ffff888025645310 R13: 0000000000000083 R14: 0000000000000005 R15: 0000000000000000 FS: 00007fbda6921c80(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000208db000 CR3: 0000000022cf7000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] fast_dput+0x204/0x410 fs/dcache.c:761 dput+0xe4/0x2b0 fs/dcache.c:839 __traverse_mounts+0x327/0x570 fs/namei.c:1398 traverse_mounts fs/namei.c:1443 [inline] handle_mounts fs/namei.c:1546 [inline] step_into+0x5e1/0x1080 fs/namei.c:1839 walk_component fs/namei.c:2007 [inline] link_path_walk+0x735/0xe70 fs/namei.c:2328 path_openat+0x249/0x31e0 fs/namei.c:3794 do_filp_open+0x234/0x490 fs/namei.c:3825 do_sys_openat2+0x13e/0x1d0 fs/open.c:1404 do_sys_open fs/open.c:1419 [inline] __do_sys_openat fs/open.c:1435 [inline] __se_sys_openat fs/open.c:1430 [inline] __x64_sys_openat+0x247/0x290 fs/open.c:1430 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7fbda651a477 Code: 10 00 00 00 44 8b 54 24 e0 48 89 44 24 c0 48 8d 44 24 d0 48 89 44 24 c8 44 89 c2 4c 89 ce bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 10 48 8b 15 82 69 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffee481cc38 EFLAGS: 00000287 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000561a96caa550 RCX: 00007fbda651a477 RDX: 0000000000090800 RSI: 0000561a96c97ff0 RDI: 00000000ffffff9c RBP: 0000561a96cc4720 R08: 0000000000090800 R09: 0000561a96c97ff0 R10: 0000000000000000 R11: 0000000000000287 R12: 0000561a96c97ff0 R13: 00000000000000fd R14: 0000561a954061c4 R15: 0000000000000000