INFO: task syz.0.2005:13945 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2005 state:D stack:27416 pid:13945 tgid:13933 ppid:5809 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xfe4/0x5e10 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 bdev_open+0xa2/0xe40 block/bdev.c:962 bdev_file_open_by_dev block/bdev.c:1076 [inline] bdev_file_open_by_dev+0x179/0x210 block/bdev.c:1051 setup_bdev_super+0x385/0x730 fs/super.c:1609 get_tree_bdev_flags+0x363/0x620 fs/super.c:1689 vfs_get_tree+0x92/0x320 fs/super.c:1751 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount fs/namespace.c:3712 [inline] path_mount+0x7d0/0x23c0 fs/namespace.c:4022 do_mount fs/namespace.c:4035 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount fs/namespace.c:4201 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:4201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fedbcd9aeb9 RSP: 002b:00007fedbdb6e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fedbd016360 RCX: 00007fedbcd9aeb9 RDX: 0000200000000040 RSI: 00002000000001c0 RDI: 00002000000000c0 RBP: 00007fedbce08c1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000800000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fedbd0163f8 R14: 00007fedbd016360 R15: 00007ffc26cde9e8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 5 locks held by kworker/1:1/43: #0: ffff888021a84d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc90000b37c98 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffff88802b69d198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff88802b69d198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff888145778518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff888145778518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff888145778518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff888145778518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff888145778518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2bd2/0x4af0 drivers/usb/core/hub.c:5953 #4: ffff88802b20de68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff88802b20de68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff88802b20de68 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff88802b20de68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x2bfb/0x4af0 drivers/usb/core/hub.c:5953 2 locks held by getty/5567: #0: ffff888037b950a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 1 lock held by udevd/6614: #0: ffff888142732358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:962 2 locks held by syz.0.2005/13945: #0: ffff8880295ae0e0 (&type->s_umount_key#92/1){+.+.}-{4:4}, at: alloc_super+0x244/0xd20 fs/super.c:344 #1: ffff888142732358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xa2/0xe40 block/bdev.c:962 2 locks held by syz.6.2506/16051: 2 locks held by syz.2.2508/16053: #0: ffffffff903f8c48 (bpf_dispatcher_xdp.mutex){+.+.}-{4:4}, at: bpf_dispatcher_change_prog+0x38/0xa60 kernel/bpf/dispatcher.c:146 #1: ffffffff8e5efab8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311 ============================================= 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 01/13/2026 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:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 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+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xcc3/0xfe0 kernel/hung_task.c:515 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 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: 13668 Comm: kworker/0:1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Workqueue: events dvb_usb_read_remote_control RIP: 0010:debug_lockdep_rcu_enabled+0x0/0x40 kernel/rcu/update.c:319 Code: 00 00 8b 44 24 04 eb b2 89 44 24 04 e8 a9 fa ff ff 8b 44 24 04 eb aa 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 8b 05 06 95 40 05 85 c0 74 20 8b 05 b0 c4 40 05 85 c0 RSP: 0018:ffffc90000007c10 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff88813fe73680 RCX: 1ffff1100f328526 RDX: 1ffff110170848e5 RSI: ffffffff8bfa3520 RDI: ffffffff8def0f20 RBP: ffffffff90b74fb0 R08: 0000000000000000 R09: ffffed10038db22b R10: ffff88801c6d915f R11: 0000000000000001 R12: ffff8880b8424538 R13: ffff88801c6d9158 R14: ffff88801c6d9000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881245db000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000404030 CR3: 000000004be9f000 CR4: 00000000003526f0 Call Trace: select_idle_cpu kernel/sched/fair.c:7647 [inline] select_idle_sibling kernel/sched/fair.c:7882 [inline] select_task_rq_fair+0x1a0d/0x5430 kernel/sched/fair.c:8581 select_task_rq kernel/sched/core.c:3497 [inline] try_to_wake_up+0x9f3/0x1a60 kernel/sched/core.c:4206 hrtimer_wakeup+0x47/0x60 kernel/time/hrtimer.c:2013 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x516/0x990 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x397/0x8c0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x109/0x3c0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2037 [inline] RIP: 0010:vprintk_emit+0x553/0x6b0 kernel/printk/printk.c:2425 Code: 00 4d 85 ed 0f 85 1b 01 00 00 e8 28 21 21 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 f6 1b 21 00 48 85 ed 0f 85 27 01 00 00 08 21 21 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00 RSP: 0018:ffffc9001c0d7a08 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000017 RCX: ffffffff81e5db6a RDX: ffff88805e174980 RSI: ffffffff81e5db74 RDI: ffff88805e174980 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff9200381af43 R13: 0000000000000200 R14: ffff88801ea824c0 R15: ffffc9001c0d7ad0 _printk+0xcf/0x110 kernel/printk/printk.c:2451 m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline] m920x_rc_core_query.cold+0x13/0x30 drivers/media/usb/dvb-usb/m920x.c:226 dvb_usb_read_remote_control+0xdd/0x1b0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:261 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3421 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246