INFO: task syz.3.6591:838 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.3.6591 state:D stack:27304 pid:838 tgid:837 ppid:28435 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776
bdev_release+0x1a9/0x650 block/bdev.c:1145
blkdev_release+0x15/0x20 block/fops.c:706
__fput+0x44c/0xa70 fs/file_table.c:468
task_work_run+0x1d4/0x260 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
exit_to_user_mode_loop+0xff/0x4f0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f561d78f749
RSP: 002b:00007f561e5fb038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f561d9e5fa0 RCX: 00007f561d78f749
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007f561d813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f561d9e6038 R14: 00007f561d9e5fa0 R15: 00007ffd15077cb8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3419e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3419e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3419e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:25/16196:
#0: ffff88801badf148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3236
#1: ffffc900048ffb80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3237
#2: ffffffff8f71ceb0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7a0 net/core/net_namespace.c:670
#3: ffffffff8e347400 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3816
2 locks held by getty/19046:
#0: ffff88814c39d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900045d12f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211
7 locks held by kworker/1:10/27398:
1 lock held by udevd/29896:
#0: ffff88802610f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962
1 lock held by syz.3.6591/838:
#0: ffff88802610f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1145
1 lock held by syz.4.7250/5426:
#0: ffff88802610f358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1305
1 lock held by syz.4.7250/5428:
#0: ffff88802610f358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1305
1 lock held by syz.4.7250/5429:
#0: ffff88802610f358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1305
=============================================
NMI backtrace for cpu 0
CPU: 0 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+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [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:346 [inline]
watchdog+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 25428 Comm: kworker/1:4 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 legacy_dvb_usb_read_remote_control
RIP: 0010:__sanitizer_cov_trace_cmp8+0x4/0x90 kernel/kcov.c:294
Code: 89 74 11 18 48 89 44 11 20 e9 88 d5 a5 09 cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <48> 8b 04 24 65 48 8b 0c 25 08 30 c3 92 65 8b 15 28 3a 01 11 81 e2
RSP: 0018:ffffc90000a08e20 EFLAGS: 00000006
RAX: 1ffffffff1c2e75d RBX: ffffffffffffffff RCX: dffffc0000000000
RDX: 000003a900000000 RSI: 000001fb63109b96 RDI: 00000000018eb2e7
RBP: 000001fb63109b96 R08: ffffffff81b010b7 R09: ffffffff99d2b508
R10: dffffc0000000000 R11: ffffffff81692c50 R12: 000001a917432a35
R13: 00000000018eb2e7 R14: ffff8880b87284a0 R15: 00000000000569bc
FS: 0000000000000000(0000) GS:ffff888125aed000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4b32fb7198 CR3: 00000000763fa000 CR4: 00000000003526f0
DR0: 0000000000000004 DR1: 000000000000e613 DR2: 0000100000000403
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
timekeeping_cycles_to_ns kernel/time/timekeeping.c:387 [inline]
timekeeping_get_ns kernel/time/timekeeping.c:404 [inline]
ktime_get_update_offsets_now+0x116/0x3d0 kernel/time/timekeeping.c:2573
hrtimer_update_base kernel/time/hrtimer.c:633 [inline]
hrtimer_interrupt+0x132/0xaa0 kernel/time/hrtimer.c:1885
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 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+0x4d0/0x5f0 kernel/printk/printk.c:2425
Code: 0f 84 34 ff ff ff e8 4f 62 20 00 fb eb 44 e8 47 62 20 00 e8 62 50 c3 09 4d 85 f6 74 94 e8 38 62 20 00 fb 48 c7 c7 a0 58 33 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 28 26
RSP: 0018:ffffc90000be7740 EFLAGS: 00000293
RAX: ffffffff81a19158 RBX: ffffffff81a18fb1 RCX: ffff888044e08000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e3358a0
RBP: ffffc90000be7850 R08: ffffffff8fc3a577 R09: 1ffffffff1f874ae
R10: dffffc0000000000 R11: fffffbfff1f874af R12: 0000000000000000
R13: 0000000000000017 R14: 0000000000000200 R15: 1ffff9200017ceec
_printk+0xcf/0x120 kernel/printk/printk.c:2451
m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline]
m920x_rc_query+0x2f6/0x830 drivers/media/usb/dvb-usb/m920x.c:-1
legacy_dvb_usb_read_remote_control+0x100/0x470 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123
process_one_work+0x93a/0x15a0 kernel/workqueue.c:3261
process_scheduled_works kernel/workqueue.c:3344 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246