INFO: task kworker/1:6:5780 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/1:6 state:D stack:21000 pid:5780 tgid:5780 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f9/0x5500 kernel/sched/core.c:7197 __schedule_loop kernel/sched/core.c:7276 [inline] schedule+0x164/0x360 kernel/sched/core.c:7291 schedule_timeout+0xc3/0x2c0 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+0x2cc/0x5e0 kernel/sched/completion.c:153 i2c_del_adapter+0x5c0/0x790 drivers/i2c/i2c-core-base.c:1813 dvb_usb_i2c_exit+0x64/0xb0 drivers/media/usb/dvb-usb/dvb-usb-i2c.c:46 dvb_usb_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:144 [inline] dvb_usb_device_exit+0x1cb/0x360 drivers/media/usb/dvb-usb/dvb-usb-init.c:338 cxusb_probe+0x60f/0x710 drivers/media/usb/dvb-usb/cxusb.c:1663 usb_probe_interface+0x659/0xc70 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x267/0xaf0 drivers/base/dd.c:707 __driver_probe_device+0x1e2/0x350 drivers/base/dd.c:869 driver_probe_device+0x4f/0x240 drivers/base/dd.c:899 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1027 bus_for_each_drv+0x25b/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c8/0x450 drivers/base/dd.c:1099 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1154 bus_probe_device+0x12d/0x220 drivers/base/bus.c:620 device_add+0x7ec/0xb90 drivers/base/core.c:3702 usb_set_configuration+0x1a87/0x2110 drivers/usb/core/message.c:2268 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250 usb_probe_device+0x1c4/0x3b0 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x267/0xaf0 drivers/base/dd.c:707 __driver_probe_device+0x1e2/0x350 drivers/base/dd.c:869 driver_probe_device+0x4f/0x240 drivers/base/dd.c:899 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1027 bus_for_each_drv+0x25b/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c8/0x450 drivers/base/dd.c:1099 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1154 bus_probe_device+0x12d/0x220 drivers/base/bus.c:620 device_add+0x7ec/0xb90 drivers/base/core.c:3702 usb_new_device+0x9f8/0x16e0 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+0x2a49/0x4f60 drivers/usb/core/hub.c:5953 process_one_work+0x98b/0x1630 kernel/workqueue.c:3306 process_scheduled_works kernel/workqueue.c:3389 [inline] worker_thread+0xb49/0x1140 kernel/workqueue.c:3470 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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 khungtaskd/39: #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777 2 locks held by getty/5365: #0: ffff888035f210a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 5 locks held by kworker/1:6/5780: #0: ffff88801fec9138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3281 #1: ffffc90005ab7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3282 #2: ffff888029d7e210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1038 [inline] #2: ffff888029d7e210 (&dev->mutex){....}-{4:4}, at: hub_event+0x17c/0x4f60 drivers/usb/core/hub.c:5899 #3: ffff8880315fa210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1038 [inline] #3: ffff8880315fa210 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1074 #4: ffff8880383371d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1038 [inline] #4: ffff8880383371d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1074 4 locks held by udevd/5843: #0: ffff88803ecafec8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb8/0xe20 fs/seq_file.c:183 #1: ffff88803aa2e078 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff88805b888b48 (kn->active#20){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff88805b888b48 (kn->active#20){.+.+}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff8880315fa210 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:1043 [inline] #3: ffff8880315fa210 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 1 lock held by syz.1.1539/10527: #0: ffff888039b800e8 (&kvm->slots_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #0: ffff888039b800e8 (&kvm->slots_lock){+.+.}-{4:4}, at: kvm_vm_ioctl_set_memory_region+0x5e/0xb0 virt/kvm/kvm_main.c:2146 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 39 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 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:162 [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:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:37 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline] RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline] RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:208 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 e9 40 af c1 09 cc 89 f6 31 d2 e9 96 3f 7d 03 66 0f 1f 44 00 RSP: 0018:ffffffff8de07bb0 EFLAGS: 00000046 RAX: 000000000005126e RBX: ffff8880b8623c40 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000005126e RDI: 0000000000000838 RBP: ffffffff8de07c68 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: ffffffff81749440 R12: 000000000005126e R13: dffffc0000000000 R14: 0000000010003e13 R15: 0000000000000020 FS: 0000000000000000(0000) GS:ffff888125cc7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7382eadd58 CR3: 000000002be64000 CR4: 00000000003526f0 Call Trace: apic_write arch/x86/include/asm/apic.h:405 [inline] lapic_next_event+0x11/0x20 arch/x86/kernel/apic/apic.c:418 clockevents_program_event+0x385/0x630 kernel/time/clockevents.c:372 hrtimer_rearm kernel/time/hrtimer.c:2141 [inline] __hrtimer_rearm_deferred+0x273/0x460 kernel/time/hrtimer.c:2161 hrtimer_rearm_deferred_tif include/linux/hrtimer_rearm.h:53 [inline] hrtimer_rearm_deferred include/linux/hrtimer_rearm.h:62 [inline] irqentry_exit_to_kernel_mode_after_preempt include/linux/irq-entry-common.h:502 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:550 [inline] irqentry_exit+0x6b2/0x760 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: 7b 6b 02 e9 83 cc 03 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 43 cb 15 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffffff8de07dc0 EFLAGS: 00000242 RAX: 0000000000222429 RBX: ffffffff8199caaa RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8d747b0a RDI: ffffffff8baa6d60 RBP: ffffffff8de07eb0 R08: ffff8880b8633d1b R09: 1ffff110170c67a3 R10: dffffc0000000000 R11: ffffed10170c67a4 R12: 0000000000000000 R13: 1ffffffff1bdfdd8 R14: 0000000000000000 R15: 1ffffffff1bdfdd8 arch_safe_halt arch/x86/kernel/process.c:766 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x36a/0x5f0 kernel/sched/idle.c:352 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451 rest_init+0x2de/0x300 init/main.c:762 start_kernel+0x38a/0x3e0 init/main.c:1220 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x157