INFO: task syz.0.749:8827 blocked for more than 144 seconds. Not tainted 6.15.0-rc6-syzkaller-00105-g088d13246a46 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.749 state:D stack:27992 pid:8827 tgid:8783 ppid:5812 task_flags:0x400640 flags:0x00000006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x2ff/0x4e0 kernel/sched/completion.c:116 wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264 coredump_wait fs/coredump.c:419 [inline] do_coredump+0x887/0x4480 fs/coredump.c:576 get_signal+0x22e3/0x26d0 kernel/signal.c:3019 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f86a804f830 RSP: 002b:00007f86a8f3b3f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000000 RBX: 00007f86a83b6168 RCX: 00007f86a818e969 RDX: 00007f86a8f3b400 RSI: 00007f86a8f3b530 RDI: 000000000000000b RBP: 00007f86a83b6160 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f86a83b616c R13: 0000000000000000 R14: 00007ffce96fbad0 R15: 00007ffce96fbbb8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e3bfc00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3bfc00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e3bfc00 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 2 locks held by kworker/u8:3/37: 11 locks held by kworker/1:1/48: 2 locks held by getty/5574: #0: ffff88814dc400a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900033532f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz.5.1243/10671: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00105-g088d13246a46 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 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+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 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: 48 Comm: kworker/1:1 Not tainted 6.15.0-rc6-syzkaller-00105-g088d13246a46 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:__lock_acquire+0x191/0x1ba0 kernel/locking/lockdep.c:5172 Code: 65 8b 15 7a 46 0c 12 85 c9 44 89 e9 44 8b ac 24 c8 00 00 00 0f 95 c0 85 d2 0f 95 c2 41 c1 e2 0f c1 e1 10 0f b6 d2 45 0f b7 d2 <41> c1 e0 13 8d 04 50 8b 14 24 81 e1 00 00 03 00 41 c1 e5 14 c1 e0 RSP: 0018:ffffc90000a08688 EFLAGS: 00000006 RAX: 0000000000000001 RBX: ffff888021ef30e8 RCX: 0000000000020000 RDX: 0000000000000000 RSI: ffff888021ef30c0 RDI: ffff888021ef30e8 RBP: ffff888021ef2f30 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: ffffffff8e3bfc00 R12: 0000000000000001 R13: 0000000000000000 R14: ffff888021ef2440 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124adf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f10aff8 CR3: 000000000e180000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xb8/0xd0 mm/kasan/generic.c:548 insert_work+0x36/0x230 kernel/workqueue.c:2183 __queue_work+0x3f8/0x10f0 kernel/workqueue.c:2345 call_timer_fn+0x197/0x620 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1835 [inline] __run_timers+0x569/0x960 kernel/time/timer.c:2414 __run_timer_base kernel/time/timer.c:2426 [inline] __run_timer_base kernel/time/timer.c:2418 [inline] run_timer_base+0x114/0x190 kernel/time/timer.c:2435 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2445 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_flush_all+0x9a2/0xc60 kernel/printk/printk.c:3227 Code: 00 e8 b2 12 28 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 80 49 20 00 48 85 db 0f 85 55 01 00 00 e8 02 4e 20 00 fb 4c 89 e0 <48> c1 e8 03 42 80 3c 38 00 0f 84 11 ff ff ff 4c 89 e7 e8 f7 cb 85 RSP: 0018:ffffc90000b962a8 EFLAGS: 00000283 RAX: ffffffff8f0cafb8 RBX: 0000000000000000 RCX: ffffc9001b759000 RDX: 0000000000100000 RSI: ffffffff819af83e RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8f0cafb8 R13: ffffffff8f0caf60 R14: ffffc90000b96338 R15: dffffc0000000000 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 dev_vprintk_emit drivers/base/core.c:4917 [inline] dev_printk_emit+0xfa/0x140 drivers/base/core.c:4928 __dev_printk+0xf5/0x270 drivers/base/core.c:4940 _dev_info+0xe4/0x120 drivers/base/core.c:4986 usb_get_langid drivers/usb/core/message.c:936 [inline] usb_string+0x5e6/0x670 drivers/usb/core/message.c:984 uclogic_params_huion_init+0x2a8/0x12c0 drivers/hid/hid-uclogic-params.c:878 uclogic_params_init+0x474/0xcb0 drivers/hid/hid-uclogic-params.c:1713 uclogic_probe+0x16c/0x380 drivers/hid/hid-uclogic-core.c:183 __hid_device_probe drivers/hid/hid-core.c:2717 [inline] hid_device_probe+0x357/0x710 drivers/hid/hid-core.c:2754 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:657 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957 bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1a70 drivers/base/core.c:3692 hid_add_device+0x373/0xa60 drivers/hid/hid-core.c:2900 usbhid_probe+0xd38/0x13f0 drivers/hid/usbhid/hid-core.c:1432 usb_probe_interface+0x300/0x9c0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:657 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957 bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1a70 drivers/base/core.c:3692 usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250 usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:657 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957 bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537 device_add+0x1148/0x1a70 drivers/base/core.c:3692 usb_new_device+0xd07/0x1a20 drivers/usb/core/hub.c:2663 hub_port_connect drivers/usb/core/hub.c:5531 [inline] hub_port_connect_change drivers/usb/core/hub.c:5671 [inline] port_event drivers/usb/core/hub.c:5831 [inline] hub_event+0x2eb7/0x4fa0 drivers/usb/core/hub.c:5913 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245