INFO: task syz.4.3606:18610 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.3606 state:D stack:27176 pid:18610 ppid:14809 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6701
schedule+0xbd/0x170 kernel/sched/core.c:6775
schedule_timeout+0xc1/0x2d0 kernel/time/timer.c:2144
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion+0x2c6/0x5a0 kernel/sched/completion.c:148
io_wq_exit_workers io_uring/io-wq.c:1270 [inline]
io_wq_put_and_exit+0x493/0x820 io_uring/io-wq.c:1298
io_uring_clean_tctx+0x12f/0x1b0 io_uring/tctx.c:204
io_uring_cancel_generic+0x610/0x6c0 io_uring/io_uring.c:3507
io_uring_files_cancel include/linux/io_uring.h:69 [inline]
do_exit+0x5f4/0x2530 kernel/exit.c:836
do_group_exit+0x22d/0x2f0 kernel/exit.c:1032
get_signal+0x12a6/0x1390 kernel/signal.c:2915
arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:213
__syscall_exit_to_user_mode_work kernel/entry/common.c:294 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:305
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fededb9e2d9
RSP: 002b:00007fedee9960e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007fedede25fa8 RCX: 00007fededb9e2d9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fedede25fac
RBP: 00007fedede25fa0 R08: 0000000000745b08 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fedede26038 R14: 00007ffda28eb2e0 R15: 00007ffda28eb3c8
Showing all locks held in the system:
6 locks held by ksoftirqd/0/16:
1 lock held by khungtaskd/29:
#0: ffffffff8df320e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8df320e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8df320e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6669
2 locks held by getty/5527:
#0: ffff88803319a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1:
ffffc9000327e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
8 locks held by kworker/0:4/5810:
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf59/0xfa0 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5810 Comm: kworker/0:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:sched_clock+0x12/0x60 arch/x86/kernel/tsc.c:283
Code: 3d 20 e8 92 8a 0f 94 c0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 f3 0f 1e fa 55 53 e8 c5 4b 56 00 65 ff 05 16 73 d2 7e 29 a4 61 09 48 89 c3 31 f6 65 ff 0d 05 73 d2 7e 40 0f 94 c5 40
RSP: 0018:ffffc90000007cc8 EFLAGS: 00000006
RAX: ffffffff813144eb RBX: 0000000000000006 RCX: ffff88807eb71e00
RDX: 0000000000000100 RSI: ffff8880b8c3c258 RDI: ffff88807eb729d8
RBP: ffffc90000007dc0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000fa4 R12: ffff88807eb729d8
R13: 1ffff1100fd6e51c R14: ffff88807eb728e0 R15: ffff88807eb729fc
FS: 0000000000000000(0000) GS:ffff8880b8c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ee1b3b0040 CR3: 0000000076529000 CR4: 00000000003506f0
Call Trace:
__lock_pin_lock kernel/locking/lockdep.c:5560 [inline]
lock_pin_lock+0x211/0x3c0 kernel/locking/lockdep.c:5882
rq_pin_lock kernel/sched/sched.h:1611 [inline]
rq_lock kernel/sched/sched.h:1689 [inline]
ttwu_queue kernel/sched/core.c:4026 [inline]
try_to_wake_up+0x5e1/0x10e0 kernel/sched/core.c:4349
wakeup_softirqd kernel/softirq.c:80 [inline]
handle_softirqs+0x605/0x820 kernel/softirq.c:601
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2008 [inline]
RIP: 0010:vprintk_emit+0x46f/0x610 kernel/printk/printk.c:2340
Code: 85 3f 01 00 00 e8 61 aa 1b 00 45 89 f7 48 85 db 48 8b 1c 24 75 07 e8 50 aa 1b 00 eb 06 e8 49 aa 1b 00 fb 48 c7 c7 c0 64 f2 8d <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 89 b2
RSP: 0018:ffffc90004a0f280 EFLAGS: 00000246
RAX: ffffffff816be667 RBX: ffffffff816be50b RCX: 0000000000100000
RDX: ffffc90017728000 RSI: 00000000000fffff RDI: ffffffff8df264c0
RBP: ffffc90004a0f370 R08: ffffffff91ff150f R09: 1ffffffff23fe2a1
R10: dffffc0000000000 R11: fffffbfff23fe2a2 R12: dffffc0000000000
R13: 1ffff92000941e54 R14: 0000000000000024 R15: 0000000000000024
_printk+0xde/0x130 kernel/printk/printk.c:2366
__dynamic_pr_debug+0x1a3/0x260 lib/dynamic_debug.c:879
__kernfs_remove+0x827/0x830 fs/kernfs/dir.c:1464
kernfs_remove_by_name_ns+0xdc/0x150 fs/kernfs/dir.c:1695
kernfs_remove_by_name include/linux/kernfs.h:624 [inline]
sysfs_unmerge_group+0xd3/0x130 fs/sysfs/group.c:372
rpm_sysfs_remove drivers/base/power/sysfs.c:826 [inline]
dpm_sysfs_remove+0x76/0xc0 drivers/base/power/sysfs.c:835
device_del+0x251/0x910 drivers/base/core.c:3931
device_unregister+0x20/0xc0 drivers/base/core.c:3997
usb_remove_ep_devs+0x50/0x80 drivers/usb/core/endpoint.c:188
usb_disconnect+0x557/0x8a0 drivers/usb/core/hub.c:2339
hub_port_connect drivers/usb/core/hub.c:5374 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5674 [inline]
port_event drivers/usb/core/hub.c:5838 [inline]
hub_event+0x1d69/0x4a80 drivers/usb/core/hub.c:5920
process_one_work kernel/workqueue.c:2657 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293