INFO: task kworker/1:2:796 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:2 state:D stack:21024 pid:796 tgid:796 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6908
__schedule_loop kernel/sched/core.c:6990 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7005
schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153
i2c_del_adapter+0x5c0/0x790 drivers/i2c/i2c-core-base.c:1814
dvb_usbv2_probe+0x4c3/0x3d40 drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:993
usb_probe_interface+0x668/0xc90 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x267/0xaf0 drivers/base/dd.c:661
__driver_probe_device+0x18c/0x320 drivers/base/dd.c:803
driver_probe_device+0x4f/0x240 drivers/base/dd.c:833
__device_attach_driver+0x2d4/0x4c0 drivers/base/dd.c:961
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c5/0x450 drivers/base/dd.c:1033
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1088
bus_probe_device+0x12a/0x220 drivers/base/bus.c:574
device_add+0x7b6/0xb70 drivers/base/core.c:3689
usb_set_configuration+0x1a87/0x2110 drivers/usb/core/message.c:2208
usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
usb_probe_device+0x1c4/0x3b0 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x267/0xaf0 drivers/base/dd.c:661
__driver_probe_device+0x18c/0x320 drivers/base/dd.c:803
driver_probe_device+0x4f/0x240 drivers/base/dd.c:833
__device_attach_driver+0x2d4/0x4c0 drivers/base/dd.c:961
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c5/0x450 drivers/base/dd.c:1033
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1088
bus_probe_device+0x12a/0x220 drivers/base/bus.c:574
device_add+0x7b6/0xb70 drivers/base/core.c:3689
usb_new_device+0xa08/0x16f0 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+0x2a1c/0x4f30 drivers/usb/core/hub.c:5953
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358
worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task syz.6.3444:6868 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.3444 state:D stack:28160 pid:6868 tgid:6850 ppid:31395 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6908
__schedule_loop kernel/sched/core.c:6990 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7005
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7062
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
device_lock include/linux/device.h:895 [inline]
usbdev_open+0x182/0x770 drivers/usb/core/devio.c:1054
chrdev_open+0x4cd/0x5e0 fs/char_dev.c:411
do_dentry_open+0x785/0x14e0 fs/open.c:949
vfs_open+0x3b/0x340 fs/open.c:1081
do_open fs/namei.c:4671 [inline]
path_openat+0x2e08/0x3860 fs/namei.c:4830
do_file_open+0x23e/0x4a0 fs/namei.c:4859
do_sys_openat2+0x113/0x200 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+0x138/0x170 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fef37d5cfce
RSP: 002b:00007fef38badb28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fef38bae6c0 RCX: 00007fef37d5cfce
RDX: 0000000000008401 RSI: 00007fef38badc00 RDI: ffffffffffffff9c
RBP: 00007fef38badc00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007fef38016128 R14: 00007fef38016090 R15: 00007fef3813fa48
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
5 locks held by kworker/1:2/796:
#0: ffff8880222c6548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff8880222c6548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
#1: ffffc90003b77c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc90003b77c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
#2: ffff88802a0a2198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#2: ffff88802a0a2198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899
#3: ffff888036fc7198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#3: ffff888036fc7198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1008
#4: ffff888030fb1160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#4: ffff888030fb1160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1008
2 locks held by getty/5584:
#0: ffff8880371210a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
4 locks held by udevd/7391:
#0: ffff8880285e1668 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:183
#1: ffff88807eb89088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172
#2: ffff8880899dbd28 (kn->active#29){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880899dbd28 (kn->active#29){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173
#3: ffff888036fc7198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline]
#3: ffff888036fc7198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
1 lock held by syz.6.3444/6868:
#0: ffff88802a0a2198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#0: ffff88802a0a2198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x182/0x770 drivers/usb/core/devio.c:1054
1 lock held by syz.7.3733/7809:
#0: ffff88802a0a2198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#0: ffff88802a0a2198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x182/0x770 drivers/usb/core/devio.c:1054
1 lock held by syz.3.3938/8855:
#0: ffff88802a0a2198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#0: ffff88802a0a2198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x182/0x770 drivers/usb/core/devio.c:1054
1 lock held by syz.1.4200/9948:
#0: ffff88802a0a2198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#0: ffff88802a0a2198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x182/0x770 drivers/usb/core/devio.c:1054
3 locks held by syz-executor/10314:
#0: ffff8880b03d4ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff8880b03d4ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff8880b03d40c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346
#2: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#2: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
4 locks held by syz.9.4278/10408:
#0: ffff88806635cec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff88806635cec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff88806635c0c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346
#2: ffffffff8fd59f28 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#2: ffffffff8fd59f28 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2644
#3: ffff8880291ad2f8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 net/bluetooth/l2cap_core.c:1755
1 lock held by syz.0.4279/10406:
#0: ffffffff8fbcd688 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8fbcd688 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
2 locks held by syz.2.4280/10411:
#0: ffff8880a8ba8ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff8880a8ba8ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff8880a8ba80c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346
1 lock held by dhcpcd/10433:
#0: ffff88802a19a260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
#0: ffff88802a19a260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe10 net/packet/af_packet.c:3197
=============================================
NMI backtrace for cpu 0
CPU: 0 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 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 1453 Comm: kworker/u8:7 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:unwind_next_frame+0x1862/0x23c0 arch/x86/kernel/unwind_orc.c:663
Code: 49 0a 00 00 48 89 d0 48 c1 e8 03 0f b6 04 28 84 c0 48 8b 74 24 18 0f 85 56 0a 00 00 48 0f bf 03 48 01 c6 49 8d 56 40 4c 89 f7 5d 49 8d 5e 40 48 89 d8 48 c1 e8 03 80 3c 28 00 74 08 48 89 df
RSP: 0018:ffffc90004cdf0f8 EFLAGS: 00000287
RAX: fffffffffffffff0 RBX: ffffffff90b49350 RCX: 0000000000000000
RDX: ffffc90004cdf208 RSI: ffffc90004cdf430 RDI: ffffc90004cdf1c8
RBP: dffffc0000000000 R08: ffffc90004cdf227 R09: 0000000000000000
R10: ffffc90004cdf218 R11: fffff5200099be45 R12: ffffc90004cdf218
R13: 1ffff9200099be3b R14: ffffc90004cdf1c8 R15: 1ffffffff216926a
FS: 0000000000000000(0000) GS:ffff888125563000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe72b2bf52 CR3: 000000000e54c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000c DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:165
__set_page_owner+0x8d/0x4c0 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889
prep_new_page mm/page_alloc.c:1897 [inline]
get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2484
alloc_slab_page mm/slub.c:3267 [inline]
allocate_slab+0x83/0x660 mm/slub.c:3458
new_slab mm/slub.c:3516 [inline]
___slab_alloc+0x150/0x6b0 mm/slub.c:4390
__slab_alloc_node mm/slub.c:4456 [inline]
slab_alloc_node mm/slub.c:4832 [inline]
__do_kmalloc_node mm/slub.c:5237 [inline]
__kmalloc_node_track_caller_noprof+0x304/0x7b0 mm/slub.c:5346
kmalloc_reserve net/core/skbuff.c:635 [inline]
__alloc_skb+0x2c1/0x7d0 net/core/skbuff.c:713
alloc_skb include/linux/skbuff.h:1383 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline]
nsim_dev_trap_report_work+0x29a/0xb80 drivers/net/netdevsim/dev.c:922
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358
worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245