INFO: task syz-executor:5620 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-executor state:D stack:21848 pid:5620 tgid:5620 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
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
wb_wait_for_completion+0x3b2/0x700 fs/fs-writeback.c:227
sync_inodes_sb+0x224/0xbf0 fs/fs-writeback.c:3030
sync_filesystem+0x17a/0x230 fs/sync.c:64
generic_shutdown_super+0x77/0x2d0 fs/super.c:626
kill_block_super+0x44/0x90 fs/super.c:1665
xfs_kill_sb+0x15/0x50 fs/xfs/xfs_super.c:2286
deactivate_locked_super+0xbc/0x130 fs/super.c:477
cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317
task_work_run+0x1d9/0x270 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:70 [inline]
exit_to_user_mode_loop+0x1fa/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: 0033:0x7f3a78b9f097
RSP: 002b:00007ffe1afffda8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f3a78c332ca RCX: 00007f3a78b9f097
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe1afffe60
RBP: 00007ffe1afffe60 R08: 00007ffe1b000e60 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe1b000ef0
R13: 00007f3a78c332ca R14: 000000000008953a R15: 00007ffe1b000f30
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:2/36:
2 locks held by getty/5376:
#0: ffff888035f770a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/5620:
#0: ffff88805331c0d8 (&type->s_umount_key#78){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88805331c0d8 (&type->s_umount_key#78){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88805331c0d8 (&type->s_umount_key#78){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:509
#1: ffff8880256c4870 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:396 [inline]
#1: ffff8880256c4870 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x208/0xbf0 fs/fs-writeback.c:3028
2 locks held by kworker/0:5/15259:
#0: ffff88801b02b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88801b02b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc90004f07c40 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc90004f07c40 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
1 lock held by syz-executor/19293:
#0: ffff8880b873b160 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667
1 lock held by syz.9.5167/20221:
2 locks held by syz.1.5169/20227:
=============================================
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 05/09/2026
Call Trace:
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
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 15259 Comm: kworker/0:5 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 vidtv_mux_tick
RIP: 0010:rq_clock_pelt kernel/sched/pelt.h:74 [inline]
RIP: 0010:cfs_rq_clock_pelt kernel/sched/pelt.h:179 [inline]
RIP: 0010:__update_blocked_fair kernel/sched/fair.c:11131 [inline]
RIP: 0010:__sched_balance_update_blocked_averages+0x269/0xcd0 kernel/sched/fair.c:11232
Code: 03 42 0f b6 04 38 84 c0 0f 85 95 06 00 00 83 3b 01 0f 86 2d 06 00 00 49 8d bd c8 0b 00 00 48 89 f8 48 c1 e8 03 42 80 3c 38 00 <74> 05 e8 d0 bd 9a 00 4d 8b bd c8 0b 00 00 49 81 c5 d8 0b 00 00 4c
RSP: 0018:ffffc90004f070a0 EFLAGS: 00000046
RAX: 1ffff110170c7799 RBX: ffff8880b863bce0 RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8e4aecf3 RDI: ffff8880b863bcc8
RBP: ffffe8ffffcedb88 R08: ffffffff90576ff7 R09: 1ffffffff20aedfe
R10: dffffc0000000000 R11: fffffbfff20aedff R12: 1ffffd1ffff9db7c
R13: ffff8880b863b100 R14: ffffe8ffffcedbe0 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888124f59000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f12639b7000 CR3: 00000000216ec000 CR4: 0000000000350ef0
Call Trace:
sched_balance_newidle kernel/sched/fair.c:14402 [inline]
pick_task_fair+0x523/0x1320 kernel/sched/fair.c:9948
__pick_next_task+0xdb/0x3c0 kernel/sched/core.c:6144
pick_next_task kernel/sched/core.c:-1 [inline]
__schedule+0x901/0x56c0 kernel/sched/core.c:7149
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
schedule_hrtimeout_range_clock+0x15b/0x330 kernel/time/sleep_timeout.c:216
schedule_hrtimeout_range kernel/time/sleep_timeout.c:263 [inline]
usleep_range_state+0xf6/0x180 kernel/time/sleep_timeout.c:373
usleep_range include/linux/delay.h:77 [inline]
vidtv_mux_tick+0x1fdf/0x24b0 drivers/media/test-drivers/vidtv/vidtv_mux.c:459
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