INFO: task kworker/1:4:5871 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:4 state:D stack:22456 pid:5871 tgid:5871 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0xfe6/0x5fa0 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:6964
schedule_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2e7/0x4c0 kernel/sched/completion.c:121
i2c_del_adapter+0x62d/0x820 drivers/i2c/i2c-core-base.c:1814
dvb_usbv2_i2c_exit drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:86 [inline]
dvb_usbv2_exit.isra.0+0x47f/0xb40 drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:844
dvb_usbv2_probe+0x669/0x970 drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:993
usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:583 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:661
__driver_probe_device+0x1de/0x400 drivers/base/dd.c:803
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:833
__device_attach_driver+0x1df/0x340 drivers/base/dd.c:961
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1033
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1088
bus_probe_device+0x64/0x160 drivers/base/bus.c:574
device_add+0x11d9/0x1950 drivers/base/core.c:3689
usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2210
usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:583 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:661
__driver_probe_device+0x1de/0x400 drivers/base/dd.c:803
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:833
__device_attach_driver+0x1df/0x340 drivers/base/dd.c:961
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1033
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1088
bus_probe_device+0x64/0x160 drivers/base/bus.c:574
device_add+0x11d9/0x1950 drivers/base/core.c:3689
usb_new_device.cold+0x685/0x115c drivers/usb/core/hub.c:2695
hub_port_connect drivers/usb/core/hub.c:5567 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x314d/0x4af0 drivers/usb/core/hub.c:5953
process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x5da/0xe40 kernel/workqueue.c:3421
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
INFO: task syz.0.1:5914 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1 state:D stack:26488 pid:5914 tgid:5913 ppid:5807 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0xfe6/0x5fa0 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:6964
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
device_lock include/linux/device.h:895 [inline]
usbdev_open+0x1b6/0x870 drivers/usb/core/devio.c:1054
chrdev_open+0x234/0x6a0 fs/char_dev.c:411
do_dentry_open+0x6d8/0x1660 fs/open.c:949
vfs_open+0x82/0x3f0 fs/open.c:1081
do_open fs/namei.c:4671 [inline]
path_openat+0x208c/0x31a0 fs/namei.c:4830
do_file_open+0x20e/0x430 fs/namei.c:4859
do_sys_openat2+0x10d/0x1e0 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6f88d5c84e
RSP: 002b:00007f6f89cf9b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f6f89cfa6c0 RCX: 00007f6f88d5c84e
RDX: 0000000000101301 RSI: 00007f6f89cf9c00 RDI: ffffffffffffff9c
RBP: 00007f6f89cf9c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007f6f89016038 R14: 00007f6f89015fa0 R15: 00007ffcb6281608
Showing all locks held in the system:
3 locks held by kworker/u8:0/12:
#0: ffff88814c908948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232
#1: ffffc90000117d08 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233
#2: ffffffff903ffba8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff903ffba8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11f/0x1360 net/ipv6/addrconf.c:4194
1 lock held by khungtaskd/31:
#0: ffffffff8e5e2fe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:302 [inline]
#0: ffffffff8e5e2fe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e5e2fe0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:5/79:
#0: ffff8880b843acd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline]
#0: ffff8880b843acd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632
#1: ffff8880b8424608 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:225 [inline]
#1: ffff8880b8424608 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2b71/0x5fa0 kernel/sched/core.c:6861
4 locks held by klogd/5165:
#0: ffff8880b843acd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline]
#0: ffff8880b843acd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632
#1: ffff8880b8424608 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:225 [inline]
#1: ffff8880b8424608 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2b71/0x5fa0 kernel/sched/core.c:6861
#2: ffff888033a3d348 (&p->pi_lock){-.-.}-{2:2}, at: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline]
#2: ffff888033a3d348 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xb2/0x1a60 kernel/sched/core.c:4106
#3: ffff8880b843acd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline]
#3: ffff8880b843acd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632
1 lock held by dhcpcd/5471:
#0: ffffffff903ffba8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff903ffba8 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x1bd/0x1f10 net/ipv4/devinet.c:1120
2 locks held by getty/5562:
#0: ffff88814d82f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
4 locks held by kworker/1:3/5815:
#0: ffff88813fe51948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232
#1: ffffc900043f7d08 (ser_release_work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233
#2: ffffffff903ffba8 (rtnl_mutex){+.+.}-{4:4}, at: ser_release+0x10e/0x280 drivers/net/caif/caif_serial.c:293
#3: ffffffff8e5eebf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
5 locks held by kworker/1:4/5871:
#0: ffff8881416f0948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232
#1: ffffc90005317d08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233
#2: ffff888143bdd198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#2: ffff888143bdd198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
#3: ffff88806cff9198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#3: ffff88806cff9198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1008
#4: ffff888069c34160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#4: ffff888069c34160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1008
1 lock held by syz.0.1/5914:
#0: ffff888143bdd198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#0: ffff888143bdd198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x1b6/0x870 drivers/usb/core/devio.c:1054
1 lock held by syz.2.456/7930:
#0: ffffffff8e5eeac0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6d0 kernel/rcu/tree.c:3828
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xcc3/0xfe0 kernel/hung_task.c:515
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 96 75 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 03 fa 10 00 fb f4 7c 34 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e207e00 EFLAGS: 00000246
RAX: 0000000000b8bc2d RBX: ffffffff8e2975c0 RCX: ffffffff8b7a84b5
RDX: 0000000000000000 RSI: ffffffff8dc522a0 RDI: ffffffff8bfaa9a0
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1017086745
R10: ffff8880b8433a2b R11: 0000000000000000 R12: fffffbfff1c52eb8
R13: 0000000000000000 R14: ffffffff90b827d0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881245b9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f93393cdff8 CR3: 000000006c5d4000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x35b/0x4b0 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
rest_init+0x251/0x260 init/main.c:757
start_kernel+0x47a/0x480 init/main.c:1206
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x122/0x130 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148