INFO: task syz.4.3867:21848 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.3867      state:D stack:21464 pid:21848 tgid:21843 ppid:19131  task_flags:0x40054c flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 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+0x7bf/0x1550 kernel/locking/mutex.c:821
 dvb_dmxdev_filter_free drivers/media/dvb-core/dmxdev.c:849 [inline]
 dvb_demux_release+0x7c/0x6b0 drivers/media/dvb-core/dmxdev.c:1249
 __fput+0x418/0xa50 fs/file_table.c:512
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x73a/0x2360 kernel/exit.c:1004
 do_group_exit+0x22d/0x2f0 kernel/exit.c:1147
 get_signal+0x121b/0x12c0 kernel/signal.c:3038
 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x104/0x730 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff07019ce59
RSP: 002b:00007ff06e3d5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: 0000000000ff8000 RBX: 00007ff070416090 RCX: 00007ff07019ce59
RDX: 00000000fffffd9d RSI: 0000200000000200 RDI: 0000000000000004
RBP: 00007ff070232e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff070416128 R14: 00007ff070416090 R15: 00007ffc3fc83bc8
 </TASK>

Showing all locks held in the system:
1 lock held by ksoftirqd/1/23:
1 lock held by khungtaskd/32:
 #0: ffffffff8e959c20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8e959c20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffffffff8e959c20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5370:
 #0: ffff888035f5e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
11 locks held by kworker/1:4/5751:
3 locks held by syz-executor/20882:
1 lock held by syz.4.3867/21848:
 #0: ffff88802bc04930 (&dmxdev->mutex){+.+.}-{4:4}, at: dvb_dmxdev_filter_free drivers/media/dvb-core/dmxdev.c:849 [inline]
 #0: ffff88802bc04930 (&dmxdev->mutex){+.+.}-{4:4}, at: dvb_demux_release+0x7c/0x6b0 drivers/media/dvb-core/dmxdev.c:1249
2 locks held by syz.6.3885/21969:
2 locks held by syz.3.4310/24148:
2 locks held by syz.0.4320/24225:
 #0: ffff888077ce4260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
 #0: ffff888077ce4260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_setsockopt+0x5a0/0x1510 net/packet/af_packet.c:3825
 #1: ffffffff8e95ff28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
 #1: ffffffff8e95ff28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
2 locks held by dhcpcd-run-hook/24226:

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
 nmi_trigger_cpumask_backtrace+0x17a/0x380 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+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
 watchdog+0xfd7/0x1030 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 21796 Comm: kworker/0:8 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events legacy_dvb_usb_read_remote_control
RIP: 0010:lockdep_recursion_inc kernel/locking/lockdep.c:465 [inline]
RIP: 0010:lock_release+0x95/0x3c0 kernel/locking/lockdep.c:5888
Code: 0d 02 00 00 65 4c 8b 3d d1 bb 9d 11 41 83 bf 9c 0b 00 00 00 0f 85 f7 01 00 00 49 81 3e 20 c5 03 94 0f 84 ea 01 00 00 9c 5b fa <48> c7 c7 e8 da ff 8d e8 bf 8e 12 0a 65 ff 05 88 00 9e 11 c7 44 24
RSP: 0018:ffffc90000007858 EFLAGS: 00000006
RAX: 0000000000000000 RBX: 0000000000000206 RCX: 0000000000000102
RDX: ffffc90000007901 RSI: ffffffff8c2ab760 RDI: ffffffff8c2ab720
RBP: 1ffffffff2193601 R08: ffffc90000b97ce8 R09: ffffc900000079b8
R10: dffffc0000000000 R11: fffff52000000f39 R12: ffffc90000b90000
R13: ffffffff8176e21f R14: ffffffff8e959c20 R15: ffff88807ec61f00
FS:  0000000000000000(0000) GS:ffff888125220000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005599f92d6768 CR3: 0000000053170000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 rcu_lock_release include/linux/rcupdate.h:310 [inline]
 rcu_read_unlock include/linux/rcupdate.h:871 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1183 [inline]
 unwind_next_frame+0x1baa/0x2550 arch/x86/kernel/unwind_orc.c:709
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 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+0x40/0x50 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:2705 [inline]
 slab_free mm/slub.c:6405 [inline]
 kfree+0x1c5/0x640 mm/slub.c:6720
 slab_free_after_rcu_debug+0x62/0x220 mm/slub.c:6454
 rcu_do_batch kernel/rcu/tree.c:2645 [inline]
 rcu_core+0x78b/0x10a0 kernel/rcu/tree.c:2897
 handle_softirqs+0x225/0x840 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline]
RIP: 0010:vprintk_emit+0x45d/0x560 kernel/printk/printk.c:2478
Code: 0f 84 44 ff ff ff e8 12 6b 21 00 fb eb 44 e8 0a 6b 21 00 e8 65 be 0f 0a 4d 85 f6 74 94 e8 fb 6a 21 00 fb 48 c7 c7 60 bf 94 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 fb 1b
RSP: 0018:ffffc90000b97840 EFLAGS: 00000293
RAX: ffffffff81a4f6c5 RBX: ffffffff81a4f53f RCX: ffff88807ec61f00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e94bf60
RBP: ffffc90000b978f0 R08: ffffffff9032f8f7 R09: 1ffffffff2065f1e
R10: dffffc0000000000 R11: fffffbfff2065f1f R12: 0000000000000000
R13: 0000000000000017 R14: 0000000000000200 R15: 1ffff92000172f0c
 _printk+0xdd/0x130 kernel/printk/printk.c:2504
 m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline]
 m920x_rc_query+0x2f1/0x830 drivers/media/usb/dvb-usb/m920x.c:-1
 legacy_dvb_usb_read_remote_control+0x107/0x450 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 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
 </TASK>