INFO: task kworker/1:8:5398 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:8 state:D stack:21800 pid:5398 tgid:5398 ppid:2 task_flags:0x4288060 flags:0x00080000 Workqueue: events request_firmware_work_func Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x1325/0x47d0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0xdd/0x2c0 kernel/sched/core.c:7326 lbs_wait_for_firmware_load+0x11e/0x1e0 drivers/net/wireless/marvell/libertas/firmware.c:116 lbs_remove_card+0x84/0x390 drivers/net/wireless/marvell/libertas/main.c:913 if_usb_disconnect+0xc5/0x270 drivers/net/wireless/marvell/libertas/if_usb.c:317 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:618 [inline] device_remove+0x12a/0x180 drivers/base/dd.c:610 __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372 usb_driver_release_interface drivers/usb/core/driver.c:640 [inline] usb_forced_unbind_intf+0x1a4/0x240 drivers/usb/core/driver.c:1133 usb_reset_device+0x411/0xaa0 drivers/usb/core/hub.c:6404 if_usb_reset_device.isra.0+0x21e/0x290 drivers/net/wireless/marvell/libertas/if_usb.c:400 if_usb_prog_firmware.cold+0x161/0x192 drivers/net/wireless/marvell/libertas/if_usb.c:918 lbs_fw_loaded drivers/net/wireless/marvell/libertas/firmware.c:23 [inline] helper_firmware_cb drivers/net/wireless/marvell/libertas/firmware.c:80 [inline] helper_firmware_cb+0x202/0x2e0 drivers/net/wireless/marvell/libertas/firmware.c:64 request_firmware_work_func+0x13f/0x440 drivers/base/firmware_loader/main.c:1164 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task kworker/0:8:6104 blocked for more than 146 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:8 state:D stack:21912 pid:6104 tgid:6104 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x1325/0x47d0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0xdd/0x2c0 kernel/sched/core.c:7326 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0xccc/0x1bd0 kernel/locking/mutex.c:821 device_lock include/linux/device.h:1102 [inline] device_del+0xa0/0x9b0 drivers/base/core.c:3923 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478 usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2345 hub_port_connect drivers/usb/core/hub.c:5407 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x1d0c/0x4af0 drivers/usb/core/hub.c:5953 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x69a/0xc80 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: 1 lock held by ksoftirqd/1/22: 1 lock held by khungtaskd/30: #0: ffffffff896e3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff896e3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff896e3000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by getty/2919: #0: ffff8881143630a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000452e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:4/5222: #0: ffff8881062a7540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297 #1: ffffc90002c0fd18 ( (work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298 #2: ffff88810afa41d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #2: ffff88810afa41d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 7 locks held by kworker/0:3/5236: #0: ffff8881f56397a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:667 [inline] #0: ffff8881f56397a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1653 [inline] #0: ffff8881f56397a0 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1991 [inline] #0: ffff8881f56397a0 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x2dc/0x47d0 kernel/sched/core.c:7108 #1: ffffc90002ca7d18 ((work_completion)(&(&d->rc_query_work)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298 #2: ffff8881f5625ed8 ( &base->lock ){-.-.}-{2:2}, at: lock_timer_base+0x124/0x1d0 kernel/time/timer.c:1004 #3: ffff8881f5626f98 ( &base->lock ){-.-.}-{2:2} , at: debug_object_activate+0x144/0x4b0 lib/debugobjects.c:873 #4: ffff8881f56397a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:667 [inline] ffff8881f56397a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1653 [inline] ffff8881f56397a0 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1991 [inline] ffff8881f56397a0 (&rq->__lock){-.-.}-{2:2}, at: ttwu_queue kernel/sched/core.c:4075 [inline] ffff8881f56397a0 (&rq->__lock){-.-.}-{2:2}, at: try_to_wake_up+0x707/0x1580 kernel/sched/core.c:4415 #5: ffffffff896e2f40 ( rcu_read_lock_sched){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock_sched){....}-{1:2}, at: rcu_read_lock_sched include/linux/rcupdate.h:938 [inline] rcu_read_lock_sched){....}-{1:2}, at: pfn_valid include/linux/mmzone.h:2270 [inline] rcu_read_lock_sched){....}-{1:2}, at: __virt_addr_valid+0x161/0x430 arch/x86/mm/physaddr.c:54 #6: ffffffff94195128 ( &obj_hash[i].lock ){-.-.}-{2:2} , at: debug_object_activate+0x144/0x4b0 lib/debugobjects.c:873 7 locks held by kworker/0:4/5251: 3 locks held by kworker/1:8/5398: #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0} , at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297 #1: ffffc900049cfd18 ( (work_completion)(&fw_work->work) ){+.+.}-{0:0} , at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298 #2: ffff88811cbf31a0 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:1102 [inline] , at: __device_driver_lock drivers/base/dd.c:1171 [inline] , at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1369 5 locks held by kworker/0:8/6104: #0: ffff8881062a7540 ((wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x12b1/0x1940 kernel/workqueue.c:3297 #1: ffffc9001486fd18 ( (work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x988/0x1940 kernel/workqueue.c:3298 #2: ffff88810abb41d8 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:1102 [inline] , at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff8881363a91d8 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:1102 [inline] , at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336 #4: ffff88811cbf31a0 ( &dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] ){....}-{4:4}, at: device_del+0xa0/0x9b0 drivers/base/core.c:3923 2 locks held by kworker/0:9/6108: 2 locks held by kworker/1:10/7457: 2 locks held by kworker/1:12/9385: 1 lock held by syz.4.1550/10620: #0: ffffffff896eeaa8 ( rcu_state.exp_mutex ){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 2 locks held by syz.2.1551/10619: #0: ffff88811e7fd110 (&evdev->mutex){+.+.}-{4:4} , at: evdev_release+0x79/0x420 drivers/input/evdev.c:432 #1: ffffffff896eeaa8 ( rcu_state.exp_mutex ){+.+.}-{4:4} , at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:122 nmi_trigger_cpumask_backtrace+0x21c/0x2a0 lib/nmi_backtrace.c:65 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xcb1/0x1030 kernel/hung_task.c:561 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6108 Comm: kworker/0:9 Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: events legacy_dvb_usb_read_remote_control RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:408 Code: 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1c 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d c3 cc cc cc cc e8 21 09 f1 fe eb a0 e8 aa 09 f1 RSP: 0018:ffffc90014c6f6e8 EFLAGS: 00000002 RAX: 0000000000000039 RBX: 00000000000003f8 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff832b5af5 RDI: ffffffff9423fd60 RBP: ffffffff9423fd20 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000039 R14: ffffffff940808a9 R15: ffffffff832b5a90 FS: 0000000000000000(0000) GS:ffff888268640000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055744377e7d0 CR3: 00000000094ac000 CR4: 00000000003506f0 Call Trace: serial_port_out include/linux/serial_core.h:813 [inline] serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3239 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3301 [inline] serial8250_console_write+0xe2c/0x1a50 drivers/tty/serial/8250/8250_port.c:3379 console_emit_next_record kernel/printk/printk.c:3183 [inline] console_flush_one_record+0x790/0xe50 kernel/printk/printk.c:3269 console_flush_all kernel/printk/printk.c:3343 [inline] __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0x103/0x260 kernel/printk/printk.c:3413 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479 _printk+0xcf/0x110 kernel/printk/printk.c:2504 legacy_dvb_usb_read_remote_control.cold+0x11/0x16 drivers/media/usb/dvb-usb/dvb-usb-remote.c:124 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245