INFO: task kworker/0:3:4810 blocked for more than 143 seconds. Not tainted 6.8.0-rc4-syzkaller-00034-g8d3dea210042 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:3 state:D stack:20400 pid:4810 tgid:4810 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x17d1/0x49f0 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 usb_kill_urb+0x1c9/0x300 drivers/usb/core/urb.c:713 usb_start_wait_urb+0x1b0/0x520 drivers/usb/core/message.c:65 usb_internal_control_msg drivers/usb/core/message.c:103 [inline] usb_control_msg+0x2b1/0x4c0 drivers/usb/core/message.c:154 get_bMaxPacketSize0 drivers/usb/core/hub.c:4768 [inline] hub_port_init+0xc21/0x2620 drivers/usb/core/hub.c:4964 hub_port_connect drivers/usb/core/hub.c:5412 [inline] hub_port_connect_change drivers/usb/core/hub.c:5623 [inline] port_event drivers/usb/core/hub.c:5783 [inline] hub_event+0x2908/0x50f0 drivers/usb/core/hub.c:5865 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 5 locks held by kworker/0:3/4810: #0: ffff888015389538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888015389538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc900036afd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc900036afd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffff88802456e190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:990 [inline] #2: ffff88802456e190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x50f0 drivers/usb/core/hub.c:5811 #3: ffff888024589510 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3169 [inline] #3: ffff888024589510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5380 [inline] #3: ffff888024589510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5623 [inline] #3: ffff888024589510 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5783 [inline] #3: ffff888024589510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x255f/0x50f0 drivers/usb/core/hub.c:5865 #4: ffff88802413c4a8 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5381 [inline] #4: ffff88802413c4a8 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5623 [inline] #4: ffff88802413c4a8 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5783 [inline] #4: ffff88802413c4a8 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x259d/0x50f0 drivers/usb/core/hub.c:5865 2 locks held by getty/4826: #0: ffff88802aebc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 2 locks held by syz-fuzzer/5062: 3 locks held by kworker/u4:3/13224: 1 lock held by syz-executor.2/24559: #0: ffffffff8e136340 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x550 kernel/rcu/tree.c:4064 1 lock held by syz-executor.3/24573: #0: ffffffff8e136340 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x550 kernel/rcu/tree.c:4064 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc4-syzkaller-00034-g8d3dea210042 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 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+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5066 Comm: syz-fuzzer Not tainted 6.8.0-rc4-syzkaller-00034-g8d3dea210042 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0033:0x66d63f Code: 00 48 8b 98 08 11 00 00 0f 1f 00 e8 3b 11 00 00 48 85 db 0f 85 73 03 00 00 48 3d 00 01 00 00 0f 8d 0c 01 00 00 48 8b 74 24 60 <48> 8b 8e 98 10 00 00 48 8b be a8 10 00 00 90 48 39 f9 0f 86 08 09 RSP: 002b:000000c000d61af0 EFLAGS: 00000287 RAX: 000000000000004e RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000008 RSI: 000000c000af6000 RDI: 000000000000000a RBP: 000000c000d61b60 R08: 00000000000004e8 R09: 00000000000001d0 R10: 000000000000020d R11: 0000000000000004 R12: 0000000000007b63 R13: 0000000000007956 R14: 000000c000007860 R15: 0000000000000100 FS: 000000c000d7e490 GS: 0000000000000000