INFO: task kworker/1:6:16397 blocked for more than 143 seconds. Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:6 state:D stack:20376 pid:16397 tgid:16397 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b88/0x5240 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 usb_kill_urb+0x1c5/0x2e0 drivers/usb/core/urb.c:713 usb_start_wait_urb+0x1b2/0x530 drivers/usb/core/message.c:65 usb_internal_control_msg drivers/usb/core/message.c:103 [inline] usb_control_msg+0x2b3/0x4c0 drivers/usb/core/message.c:154 get_bMaxPacketSize0 drivers/usb/core/hub.c:4815 [inline] hub_port_init+0xcbe/0x2730 drivers/usb/core/hub.c:5011 hub_port_connect drivers/usb/core/hub.c:5460 [inline] hub_port_connect_change drivers/usb/core/hub.c:5671 [inline] port_event drivers/usb/core/hub.c:5831 [inline] hub_event+0x281c/0x50f0 drivers/usb/core/hub.c:5913 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac5/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b9/0x940 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5597: #0: ffff8880317f40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036e32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 3 locks held by kworker/u8:24/11384: 5 locks held by kworker/1:6/16397: #0: ffff888145292d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888145292d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90003d57c60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003d57c60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffff888146b12198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #2: ffff888146b12198 (&dev->mutex){....}-{4:4}, at: hub_event+0x200/0x50f0 drivers/usb/core/hub.c:5859 #3: ffff888146b15510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3220 [inline] #3: ffff888146b15510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5428 [inline] #3: ffff888146b15510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline] #3: ffff888146b15510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline] #3: ffff888146b15510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2494/0x50f0 drivers/usb/core/hub.c:5913 #4: ffff888145749968 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5429 [inline] #4: ffff888145749968 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline] #4: ffff888145749968 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline] #4: ffff888145749968 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x24cd/0x50f0 drivers/usb/core/hub.c:5913 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b9/0x940 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:81 Code: 7e bf e0 f4 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 53 8e 18 00 f3 0f 1e fa fb f4 53 bf e0 f4 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197dc0 EFLAGS: 00000286 RAX: 9537fc4d6cfbfd00 RBX: ffffffff8197272e RCX: ffffffff8c2fa89c RDX: 0000000000000001 RSI: ffffffff8e64973a RDI: ffffffff8ca1b5c0 RBP: ffffc90000197f20 R08: ffff8880b8732b5b R09: 1ffff110170e656b R10: dffffc0000000000 R11: ffffed10170e656c R12: 1ffff92000032fd2 R13: 1ffff11003adbb40 R14: 0000000000000001 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff88812509a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555a9c05b600 CR3: 000000000eb38000 CR4: 0000000000350ef0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:748 default_idle_call+0x74/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x22e/0x5d0 kernel/sched/idle.c:325 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:423 start_secondary+0xfe/0x100 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x147