INFO: task syz.4.103:4897 blocked for more than 142 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.103 state:D stack:28272 pid:4897 ppid:4275 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6698
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x548/0xae0 kernel/locking/mutex.c:747
device_lock include/linux/device.h:885 [inline]
usbdev_do_ioctl drivers/usb/core/devio.c:2609 [inline]
usbdev_ioctl+0x143/0x1f20 drivers/usb/core/devio.c:2817
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbf4a39e019
RSP: 002b:00007fbf4b2c7028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fbf4a626180 RCX: 00007fbf4a39e019
RDX: 0000200000000040 RSI: 0000000080045505 RDI: 0000000000000004
RBP: 00007fbf4a43500c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbf4a626218 R14: 00007fbf4a626180 R15: 00007fff1e0563b8
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527
2 locks held by getty/4028:
#0: ffff88802fc2c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
1 lock held by syz-executor/4278:
#0: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#0: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962
2 locks held by kworker/1:3/4319:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc90004117d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
7 locks held by syz.4.103/4895:
#0: ffff8881467ba190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
#0: ffff8881467ba190 (&dev->mutex){....}-{3:3}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2609 [inline]
#0: ffff8881467ba190 (&dev->mutex){....}-{3:3}, at: usbdev_ioctl+0x143/0x1f20 drivers/usb/core/devio.c:2817
#1: ffff8881467bb118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
#1: ffff8881467bb118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1099 [inline]
#1: ffff8881467bb118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb1/0x7c0 drivers/base/dd.c:1302
#2: ffff88807ca1e190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
#2: ffff88807ca1e190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0xf8/0x8a0 drivers/usb/core/hub.c:2305
#3: ffff888057742118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
#3: ffff888057742118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1099 [inline]
#3: ffff888057742118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb1/0x7c0 drivers/base/dd.c:1302
#4: ffffffff8dd00708 (register_mutex#7){+.+.}-{3:3}, at: usb_audio_disconnect+0xd0/0x6f0 sound/usb/card.c:960
#5: ffff88807c98d170 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
#5: ffff88807c98d170 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1099 [inline]
#5: ffff88807c98d170 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb1/0x7c0 drivers/base/dd.c:1302
#6: ffffffff8dcc62c8 (register_mutex#6){+.+.}-{3:3}, at: snd_seq_midisynth_remove+0x68/0x4f0 sound/core/seq/seq_midi.c:459
1 lock held by syz.4.103/4897:
#0: ffff8881467ba190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
#0: ffff8881467ba190 (&dev->mutex){....}-{3:3}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2609 [inline]
#0: ffff8881467ba190 (&dev->mutex){....}-{3:3}, at: usbdev_ioctl+0x143/0x1f20 drivers/usb/core/devio.c:2817
1 lock held by syz.1.296/5990:
#0: ffff88807ca1e190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
#0: ffff88807ca1e190 (&dev->mutex){....}-{3:3}, at: usbdev_open+0x14e/0x7a0 drivers/usb/core/devio.c:1052
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 28 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+0x188/0x24e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf0e/0xf50 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 33 Comm: kworker/u4:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:memcmp lib/string.c:783 [inline]
RIP: 0010:bcmp+0x18a/0x220 lib/string.c:804
Code: 48 89 ef 48 8b 34 24 4c 89 ea e9 0d ff ff ff 48 85 d2 0f 84 95 00 00 00 31 db 48 8d 04 1f 48 89 c1 48 c1 e9 03 42 0f b6 0c 39 <84> c9 75 2b 0f b6 04 1f 48 8d 0c 1e 49 89 c8 49 c1 e8 03 47 0f b6
RSP: 0018:ffffc90000aa7820 EFLAGS: 00000803
RAX: ffffffff81d28525 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffc90000aa7a70 RDI: ffffffff81d28525
RBP: ffffc90000aa7990 R08: ffff888017468457 R09: 1ffff11002e8d08a
R10: dffffc0000000000 R11: ffffed1002e8d08b R12: 00002aaaaaaac000
R13: ffff888019679e00 R14: 0000000000000000 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6ed1650e9c CR3: 000000000c88e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
memcmp include/linux/fortify-string.h:549 [inline]
__text_poke+0x64a/0x840 arch/x86/kernel/alternative.c:1452
text_poke arch/x86/kernel/alternative.c:1480 [inline]
text_poke_bp_batch+0x6b5/0x850 arch/x86/kernel/alternative.c:1852
text_poke_flush arch/x86/kernel/alternative.c:1965 [inline]
text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972
arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x11f/0x240 kernel/jump_label.c:207
static_key_enable+0x16/0x20 kernel/jump_label.c:220
toggle_allocation_gate+0xba/0x470 mm/kfence/core.c:821
process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295