INFO: task kworker/1:0:24 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:0 state:D stack:21824 pid:24 tgid:24 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5258 [inline] __schedule+0x14ed/0x5040 kernel/sched/core.c:6866 __schedule_loop kernel/sched/core.c:6948 [inline] schedule+0x165/0x360 kernel/sched/core.c:6963 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153 i2c_del_adapter+0x591/0x760 drivers/i2c/i2c-core-base.c:1814 dvb_usbv2_probe+0x494/0x3d30 drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:993 usb_probe_interface+0x668/0xc90 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0xad0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:801 driver_probe_device+0x4f/0x240 drivers/base/dd.c:831 __device_attach_driver+0x279/0x430 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:500 __device_attach+0x2b8/0x430 drivers/base/dd.c:1031 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1086 bus_probe_device+0x12a/0x220 drivers/base/bus.c:574 device_add+0x7b6/0xb80 drivers/base/core.c:3689 usb_set_configuration+0x1a87/0x2110 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250 usb_probe_device+0x1c4/0x3c0 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0xad0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:801 driver_probe_device+0x4f/0x240 drivers/base/dd.c:831 __device_attach_driver+0x279/0x430 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:500 __device_attach+0x2b8/0x430 drivers/base/dd.c:1031 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1086 bus_probe_device+0x12a/0x220 drivers/base/bus.c:574 device_add+0x7b6/0xb80 drivers/base/core.c:3689 usb_new_device+0xa39/0x1720 drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x29b1/0x4ef0 drivers/usb/core/hub.c:5953 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443 kthread+0x389/0x480 kernel/kthread.c:467 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Showing all locks held in the system: 4 locks held by kworker/u8:1/13: #0: ffff88813fe29948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254 #1: ffffc90000127c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255 #2: ffffffff8f512ec8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 #3: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #3: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x36e/0x6e0 kernel/rcu/tree_exp.h:961 5 locks held by kworker/1:0/24: #0: ffff888142ad6d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254 #1: ffffc900001e7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255 #2: ffff888028f3e198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff888028f3e198 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4ef0 drivers/usb/core/hub.c:5899 #3: ffff88805bb71198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #3: ffff88805bb71198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006 #4: ffff88805bb74160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #4: ffff88805bb74160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006 1 lock held by khungtaskd/31: #0: ffffffff8e13f2a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:302 [inline] #0: ffffffff8e13f2a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e13f2a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5577: #0: ffff88814e05d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211 3 locks held by kworker/u8:22/7599: #0: ffff88814d0d9948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254 #1: ffffc900057afc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255 #2: ffffffff8f512ec8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f512ec8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4194 3 locks held by kworker/u9:0/14283: #0: ffff88807bc1c148 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254 #1: ffffc90003537c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255 #2: ffff88805bb8cec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331 1 lock held by syz-executor/14690: #0: ffffffff8f512ec8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f512ec8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978 2 locks held by syz-executor/14847: #0: ffffffff8ec69388 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:302 [inline] #0: ffffffff8ec69388 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8ec69388 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f512ec8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f512ec8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f512ec8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071 1 lock held by syz.9.1917/14963: #0: ffff888025294080 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:353 [inline] #0: ffff888025294080 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x211/0x4d0 mm/util.c:579 2 locks held by syz.9.1917/14964: #0: ffffffff8dffa488 (sched_core_mutex){+.+.}-{4:4}, at: sched_core_get+0x52/0x170 kernel/sched/core.c:485 #1: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x36e/0x6e0 kernel/rcu/tree_exp.h:961 2 locks held by syz.9.1917/14965: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:375 [inline] watchdog+0xe88/0xee0 kernel/hung_task.c:588 kthread+0x389/0x480 kernel/kthread.c:467 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 14606 Comm: kworker/u8:28 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:hlock_class kernel/locking/lockdep.c:229 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4879 [inline] RIP: 0010:__lock_acquire+0x518/0x2cf0 kernel/locking/lockdep.c:5187 Code: 1d 44 89 e0 49 ff c7 49 63 8e 00 0b 00 00 48 83 c3 28 41 89 c4 49 39 cf 0f 8d c7 00 00 00 49 83 ff 31 0f 83 83 00 00 00 8b 03 <25> ff 1f 00 00 48 0f a3 05 2b 06 0b 12 73 10 48 69 c0 c8 00 00 00 RSP: 0018:ffffc9000404f390 EFLAGS: 00000087 RAX: 00000000000487b2 RBX: ffff8880296da9b8 RCX: 0000000000000004 RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8880296da9e8 R08: ffffffff8173fd85 R09: ffffffff8e13f2a0 R10: ffffc9000404f698 R11: ffffffff81acb420 R12: 00000000ffffff05 R13: ffff8880296da9e8 R14: ffff8880296d9e40 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff888125c0c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f90c716bf98 CR3: 000000004a842000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:302 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] class_rcu_constructor include/linux/rcupdate.h:1166 [inline] unwind_next_frame+0xc2/0x23d0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6674 [inline] kmem_cache_free+0x197/0x620 mm/slub.c:6785 nsim_dev_trap_report drivers/net/netdevsim/dev.c:892 [inline] nsim_dev_trap_report_work+0x7cf/0xb80 drivers/net/netdevsim/dev.c:922 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443 kthread+0x389/0x480 kernel/kthread.c:467 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246