INFO: task syz.4.420:5741 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.420 state:D stack:24568 pid:5741 ppid:4270 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2144
do_wait_for_common kernel/sched/completion.c:85 [inline]
__wait_for_common kernel/sched/completion.c:106 [inline]
wait_for_common kernel/sched/completion.c:117 [inline]
wait_for_completion+0x2c7/0x5a0 kernel/sched/completion.c:138
i2c_del_adapter+0x611/0x760 drivers/i2c/i2c-core-base.c:1816
dvb_usb_i2c_exit+0x60/0xb0 drivers/media/usb/dvb-usb/dvb-usb-i2c.c:46
dvb_usb_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:144 [inline]
dvb_usb_device_exit+0x1c8/0x340 drivers/media/usb/dvb-usb/dvb-usb-init.c:338
usb_unbind_interface+0x1ee/0x860 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:550 [inline]
__device_release_driver drivers/base/dd.c:1260 [inline]
device_release_driver_internal+0x522/0x850 drivers/base/dd.c:1286
bus_remove_device+0x2e2/0x400 drivers/base/bus.c:531
device_del+0x6af/0xaf0 drivers/base/core.c:3885
usb_disable_device+0x3e2/0x890 drivers/usb/core/message.c:1414
usb_disconnect+0x348/0x8a0 drivers/usb/core/hub.c:2314
hub_quiesce+0x171/0x330 drivers/usb/core/hub.c:1379
hub_disconnect+0xc1/0x460 drivers/usb/core/hub.c:1785
usb_unbind_interface+0x1ee/0x860 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:550 [inline]
__device_release_driver drivers/base/dd.c:1260 [inline]
device_release_driver_internal+0x522/0x850 drivers/base/dd.c:1286
proc_ioctl+0x293/0x670 drivers/usb/core/devio.c:2358
proc_ioctl_default+0xc1/0x100 drivers/usb/core/devio.c:2401
usbdev_do_ioctl drivers/usb/core/devio.c:2757 [inline]
usbdev_ioctl+0x15a1/0x1f10 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: 0033:0x7f2369d9c629
RSP: 002b:00007f236acf1028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f236a016180 RCX: 00007f2369d9c629
RDX: 0000200000000200 RSI: 00000000c0105512 RDI: 0000000000000008
RBP: 00007f2369e32b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f236a016218 R14: 00007f236a016180 R15: 00007ffdb35639f8
INFO: task syz.4.420:5750 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.420 state:D stack:28592 pid:5750 ppid:4270 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747
device_lock include/linux/device.h:840 [inline]
usbdev_do_ioctl drivers/usb/core/devio.c:2609 [inline]
usbdev_ioctl+0x144/0x1f10 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: 0033:0x7f2369d9c629
RSP: 002b:00007f236acd0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f236a016270 RCX: 00007f2369d9c629
RDX: 0000000000000000 RSI: 0000000080045505 RDI: 0000000000000008
RBP: 00007f2369e32b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f236a016308 R14: 00007f236a016270 R15: 00007ffdb35639f8
INFO: task syz.4.420:5759 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.420 state:D stack:29168 pid:5759 ppid:4270 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747
device_lock include/linux/device.h:840 [inline]
usbdev_do_ioctl drivers/usb/core/devio.c:2609 [inline]
usbdev_ioctl+0x144/0x1f10 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: 0033:0x7f2369d9c629
RSP: 002b:00007f236ac8e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f236a016450 RCX: 00007f2369d9c629
RDX: 0000200000000000 RSI: 0000000080045505 RDI: 0000000000000008
RBP: 00007f2369e32b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f236a0164e8 R14: 00007f236a016450 R15: 00007ffdb35639f8
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2dfb0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2e7d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/27:
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by getty/4031:
#0: ffff88814d37f098 (&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+0x429/0x1390 drivers/tty/n_tty.c:2198
1 lock held by udevd/4258:
4 locks held by syz.4.420/5741:
#0: ffff888145b1f190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#0: ffff888145b1f190 (&dev->mutex){....}-{3:3}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2609 [inline]
#0: ffff888145b1f190 (&dev->mutex){....}-{3:3}, at: usbdev_ioctl+0x144/0x1f10 drivers/usb/core/devio.c:2817
#1: ffff888059798118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#1: ffff888059798118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1080 [inline]
#1: ffff888059798118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb2/0x850 drivers/base/dd.c:1283
#2: ffff88802e659190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#2: ffff88802e659190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x107/0x8a0 drivers/usb/core/hub.c:2305
#3: ffff88802e65c118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#3: ffff88802e65c118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1080 [inline]
#3: ffff88802e65c118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb2/0x850 drivers/base/dd.c:1283
1 lock held by syz.4.420/5750:
#0: ffff888145b1f190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#0: ffff888145b1f190 (&dev->mutex){....}-{3:3}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2609 [inline]
#0: ffff888145b1f190 (&dev->mutex){....}-{3:3}, at: usbdev_ioctl+0x144/0x1f10 drivers/usb/core/devio.c:2817
1 lock held by syz.4.420/5759:
#0: ffff888145b1f190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#0: ffff888145b1f190 (&dev->mutex){....}-{3:3}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2609 [inline]
#0: ffff888145b1f190 (&dev->mutex){....}-{3:3}, at: usbdev_ioctl+0x144/0x1f10 drivers/usb/core/devio.c:2817
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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+0xeee/0xf30 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: 4455 Comm: kworker/u4:12 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: bat_events batadv_nc_worker
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:check_preemption_disabled+0x56/0x110 lib/smp_processor_id.c:19
Code: 74 1f 65 48 8b 0c 25 28 00 00 00 48 3b 4c 24 08 0f 85 c4 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d c3 48 c7 04 24 00 00 00 00 9c <8f> 04 24 f7 04 24 00 02 00 00 74 cc 65 4c 8b 3d a6 c4 d5 75 41 f6
RSP: 0018:ffffc90004b2fa80 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000080000000
RDX: 0000000000000000 RSI: ffffffff8a8c23a0 RDI: ffffffff8adf0d20
RBP: ffffc90004b2fbc8 R08: dffffc0000000000 R09: 1ffffffff215ea48
R10: dffffc0000000000 R11: fffffbfff215ea49 R12: 0000000000000000
R13: 1ffff92000965f64 R14: 0000000000000246 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4f107ea4b8 CR3: 000000002e64b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline]
lock_acquire+0x1cb/0x4a0 kernel/locking/lockdep.c:5664
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0xeb/0x600 net/batman-adv/network-coding.c:719
process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295