INFO: task kworker/0:6:6638 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/0:6 state:D stack:21672 pid:6638 tgid:6638 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0xfee/0x6120 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7008
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_usb_i2c_exit+0x9f/0xf0 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+0x313/0x520 drivers/media/usb/dvb-usb/dvb-usb-init.c:338
cxusb_probe.cold+0x4d/0xc2 drivers/media/usb/dvb-usb/cxusb.c:1663
usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:643 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:721
__driver_probe_device+0x1de/0x400 drivers/base/dd.c:863
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:893
__device_attach_driver+0x1df/0x340 drivers/base/dd.c:1021
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1093
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1148
bus_probe_device+0x64/0x160 drivers/base/bus.c:613
device_add+0x11d9/0x1950 drivers/base/core.c:3691
usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2266
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:643 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:721
__driver_probe_device+0x1de/0x400 drivers/base/dd.c:863
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:893
__device_attach_driver+0x1df/0x340 drivers/base/dd.c:1021
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1093
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1148
bus_probe_device+0x64/0x160 drivers/base/bus.c:613
device_add+0x11d9/0x1950 drivers/base/core.c:3691
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+0xa23/0x19a0 kernel/workqueue.c:3276
process_scheduled_works kernel/workqueue.c:3359 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
3 locks held by kworker/1:1/42:
#0: ffff88813fe67148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc90000b27d08 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffffffff8e7f3478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
2 locks held by getty/5564:
#0: ffff88803a2f20a0 (&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
2 locks held by syz-executor/5805:
#0: ffffffff90613528 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90613528 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
#1: ffffffff8e7f3478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by syz-executor/5810:
2 locks held by syz-executor/5811:
5 locks held by kworker/0:6/6638:
#0: ffff8880216b0948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc90003c87d08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffff88802b3b71e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline]
#2: ffff88802b3b71e0 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
#3: ffff88802e41c1e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline]
#3: ffff88802e41c1e0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068
#4: ffff8880212e21a8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline]
#4: ffff8880212e21a8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068
2 locks held by syz.4.267/6892:
4 locks held by udevd/9289:
#0: ffff88807b4652f0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
#1: ffff88805eed0c88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
#2: ffff888039027788 (kn->active#21){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888039027788 (kn->active#21){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
#3: ffff88802e41c1e0 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:954 [inline]
#3: ffff88802e41c1e0 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
1 lock held by syz.0.1447/11190:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 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 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+0xd25/0x1050 kernel/hung_task.c:515
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6892 Comm: syz.4.267 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:185 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x39/0x70 kernel/kcov.c:217
Code: 65 48 8b 15 41 48 05 12 a9 00 01 ff 00 74 1b f6 c4 01 74 07 a9 00 00 ff 00 74 05 c3 cc cc cc cc 8b 82 a4 16 00 00 85 c0 74 f1 <8b> 82 80 16 00 00 83 f8 02 75 e6 48 8b 8a 88 16 00 00 8b 92 84 16
RSP: 0018:ffffc90003437008 EFLAGS: 00000046
RAX: 0000000080000002 RBX: ffff88805fa539c2 RCX: ffffffff8b8edf59
RDX: ffff8880334124c0 RSI: ffffffff8b8edf7b RDI: ffff8880334124c0
RBP: 0000000000000002 R08: 0000000000000007 R09: 0000000000000002
R10: 0000000000000002 R11: 0000000000000000 R12: ffffc90003437128
R13: ffff88805f98d600 R14: 0000000000000002 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff88812433c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b2d686f170 CR3: 000000000e598000 CR4: 00000000003526f0
Call Trace:
xa_is_node include/linux/xarray.h:1270 [inline]
xas_load+0x5b/0x5c0 lib/xarray.c:241
xas_store+0xb56/0x1a30 lib/xarray.c:797
page_cache_delete mm/filemap.c:142 [inline]
__filemap_remove_folio+0x421/0x660 mm/filemap.c:228
filemap_remove_folio+0xfc/0x270 mm/filemap.c:257
truncate_inode_folio+0x49/0x70 mm/truncate.c:176
shmem_undo_range+0x3ae/0x1570 mm/shmem.c:1145
shmem_truncate_range mm/shmem.c:1277 [inline]
shmem_evict_inode+0x39e/0xbd0 mm/shmem.c:1407
evict+0x3c2/0xad0 fs/inode.c:846
iput_final fs/inode.c:1966 [inline]
iput.part.0+0x605/0xf50 fs/inode.c:2015
iput+0x35/0x40 fs/inode.c:1981
dentry_unlink_inode+0x2a1/0x490 fs/dcache.c:467
__dentry_kill+0x1d0/0x600 fs/dcache.c:670
shrink_kill fs/dcache.c:1147 [inline]
shrink_dentry_list+0x180/0x5e0 fs/dcache.c:1174
shrink_dcache_tree+0x100/0x570 fs/dcache.c:1620
do_one_tree fs/dcache.c:1654 [inline]
shrink_dcache_for_umount+0xa7/0x400 fs/dcache.c:1671
generic_shutdown_super+0x7e/0x360 fs/super.c:624
kill_anon_super+0x3a/0x60 fs/super.c:1292
deactivate_locked_super+0xc1/0x1b0 fs/super.c:476
deactivate_super fs/super.c:509 [inline]
deactivate_super+0xe7/0x110 fs/super.c:505
cleanup_mnt+0x21f/0x450 fs/namespace.c:1312
task_work_run+0x150/0x240 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x8b8/0x2b60 kernel/exit.c:976
do_group_exit+0xd5/0x2a0 kernel/exit.c:1118
get_signal+0x1ec7/0x21e0 kernel/signal.c:3034
arch_do_signal_or_restart+0x91/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x4a0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ffbcc15cfce
Code: Unable to access opcode bytes at 0x7ffbcc15cfa4.
RSP: 002b:00007ffbca3f5f58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007ffbca3f66c0 RCX: 00007ffbcc15cfce
RDX: 00007ffbca3f5fb0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffbcc232c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffbcc416038 R14: 00007ffbcc415fa0 R15: 00007ffc671adbe8