======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
kworker/0:2/3157 is trying to acquire lock:
ffff888077550a28 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x5c/0x1050 kernel/sched/core.c:4049
but task is already holding lock:
ffff88807a602528 (&tty->write_wait){-...}-{2:2}, at: __wake_up_common_lock kernel/sched/wait.c:137 [inline]
ffff88807a602528 (&tty->write_wait){-...}-{2:2}, at: __wake_up+0xed/0x180 kernel/sched/wait.c:157
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #5 (&tty->write_wait){-...}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
__wake_up_common_lock kernel/sched/wait.c:137 [inline]
__wake_up+0xed/0x180 kernel/sched/wait.c:157
tty_port_default_wakeup+0xa5/0xf0 drivers/tty/tty_port.c:51
serial8250_tx_chars+0x629/0x830 drivers/tty/serial/8250/8250_port.c:1828
serial8250_handle_irq+0x519/0x610 drivers/tty/serial/8250/8250_port.c:1924
serial8250_default_handle_irq+0xb4/0x1a0 drivers/tty/serial/8250/8250_port.c:1941
serial8250_interrupt+0x9b/0x1c0 drivers/tty/serial/8250/8250_core.c:127
__handle_irq_event_percpu+0x291/0x9b0 kernel/irq/handle.c:156
handle_irq_event_percpu kernel/irq/handle.c:196 [inline]
handle_irq_event+0xa5/0x220 kernel/irq/handle.c:213
handle_edge_irq+0x243/0xb20 kernel/irq/chip.c:819
generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
handle_irq arch/x86/kernel/irq.c:233 [inline]
__common_interrupt+0xd7/0x1e0 arch/x86/kernel/irq.c:252
common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:242
asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:667
native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
default_idle+0xb/0x10 arch/x86/kernel/process.c:729
default_idle_call+0x81/0xc0 kernel/sched/idle.c:112
cpuidle_idle_call kernel/sched/idle.c:194 [inline]
do_idle+0x21b/0x5b0 kernel/sched/idle.c:306
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
start_kernel+0x486/0x530 init/main.c:1154
secondary_startup_64_no_verify+0xb1/0xbb
-> #4 (&port_lock_key){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
serial8250_console_write+0x170/0xf80 drivers/tty/serial/8250/8250_port.c:3362
call_console_drivers kernel/printk/printk.c:-1 [inline]
console_unlock+0xc86/0x1200 kernel/printk/printk.c:2744
vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274
_printk+0xcc/0x110 kernel/printk/printk.c:2299
register_console+0x682/0x960 kernel/printk/printk.c:3107
univ8250_console_init+0x41/0x50 drivers/tty/serial/8250/8250_core.c:690
console_init+0x177/0x5d0 kernel/printk/printk.c:3207
start_kernel+0x2f9/0x530 init/main.c:1090
secondary_startup_64_no_verify+0xb1/0xbb
-> #3 (console_owner){..-.}-{0:0}:
console_lock_spinning_enable+0x51/0x60 kernel/printk/printk.c:1805
console_unlock+0x9f8/0x1200 kernel/printk/printk.c:2741
vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274
_printk+0xcc/0x110 kernel/printk/printk.c:2299
debug_objects_oom+0x89/0x2f0 lib/debugobjects.c:473
debug_object_activate+0x409/0x480 lib/debugobjects.c:699
debug_rcu_head_queue kernel/rcu/rcu.h:176 [inline]
kvfree_call_rcu+0xb5/0x7c0 kernel/rcu/tree.c:3591
trie_update_elem+0x86e/0xc50 kernel/bpf/lpm_trie.c:396
bpf_map_update_value+0x57d/0x650 kernel/bpf/syscall.c:223
generic_map_update_batch+0x525/0x7c0 kernel/bpf/syscall.c:1430
bpf_map_do_batch+0x466/0x600 kernel/bpf/syscall.c:-1
__sys_bpf+0x601/0x670 kernel/bpf/syscall.c:-1
__do_sys_bpf kernel/bpf/syscall.c:4761 [inline]
__se_sys_bpf kernel/bpf/syscall.c:4759 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4759
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #2 (&trie->lock){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
trie_delete_elem+0x90/0x710 kernel/bpf/lpm_trie.c:467
0xffffffffa0008e02
bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline]
__bpf_prog_run include/linux/filter.h:621 [inline]
bpf_prog_run include/linux/filter.h:635 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline]
bpf_trace_run2+0x242/0x2d0 kernel/trace/bpf_trace.c:1915
trace_tlb_flush+0xe6/0x110 include/trace/events/tlb.h:38
switch_mm_irqs_off+0x6e3/0x9a0 arch/x86/mm/tlb.c:-1
context_switch kernel/sched/core.c:5035 [inline]
__schedule+0x1024/0x4390 kernel/sched/core.c:6395
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6571
preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6596
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
__raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:404 [inline]
zap_pte_range mm/memory.c:1446 [inline]
zap_pmd_range mm/memory.c:1505 [inline]
zap_pud_range mm/memory.c:1534 [inline]
zap_p4d_range mm/memory.c:1555 [inline]
unmap_page_range+0x208c/0x2520 mm/memory.c:1576
unmap_vmas+0x11b/0x230 mm/memory.c:1653
exit_mmap+0x38f/0x5f0 mm/mmap.c:3216
__mmput+0x115/0x3b0 kernel/fork.c:1127
exit_mm+0x567/0x6c0 kernel/exit.c:550
do_exit+0x5a1/0x20a0 kernel/exit.c:870
do_group_exit+0x12e/0x300 kernel/exit.c:997
get_signal+0x6ca/0x12c0 kernel/signal.c:2900
arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #1 (&rq->__lock){-.-.}-{2:2}:
_raw_spin_lock_nested+0x2e/0x40 kernel/locking/spinlock.c:368
raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
raw_spin_rq_lock kernel/sched/sched.h:1326 [inline]
rq_lock kernel/sched/sched.h:1621 [inline]
task_fork_fair+0x5c/0x350 kernel/sched/fair.c:11499
sched_cgroup_fork+0x2c6/0x320 kernel/sched/core.c:4485
copy_process+0x22d1/0x3e00 kernel/fork.c:2395
kernel_clone+0x219/0x930 kernel/fork.c:2679
kernel_thread+0xc8/0x120 kernel/fork.c:2731
rest_init+0x21/0x330 init/main.c:720
start_kernel+0x486/0x530 init/main.c:1154
secondary_startup_64_no_verify+0xb1/0xbb
-> #0 (&p->pi_lock){-.-.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain kernel/locking/lockdep.c:3788 [inline]
__lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
try_to_wake_up+0x5c/0x1050 kernel/sched/core.c:4049
autoremove_wake_function+0x13/0xf0 kernel/sched/wait.c:416
__wake_up_common+0x2a4/0x4e0 kernel/sched/wait.c:108
__wake_up_common_lock kernel/sched/wait.c:138 [inline]
__wake_up+0x108/0x180 kernel/sched/wait.c:157
tty_port_default_wakeup+0xa5/0xf0 drivers/tty/tty_port.c:51
serial8250_tx_chars+0x629/0x830 drivers/tty/serial/8250/8250_port.c:1828
serial8250_handle_irq+0x519/0x610 drivers/tty/serial/8250/8250_port.c:1924
serial8250_default_handle_irq+0xb4/0x1a0 drivers/tty/serial/8250/8250_port.c:1941
serial8250_interrupt+0x9b/0x1c0 drivers/tty/serial/8250/8250_core.c:127
__handle_irq_event_percpu+0x291/0x9b0 kernel/irq/handle.c:156
handle_irq_event_percpu kernel/irq/handle.c:196 [inline]
handle_irq_event+0xa5/0x220 kernel/irq/handle.c:213
handle_edge_irq+0x243/0xb20 kernel/irq/chip.c:819
generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
handle_irq arch/x86/kernel/irq.c:233 [inline]
__common_interrupt+0xd7/0x1e0 arch/x86/kernel/irq.c:252
common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:242
asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:667
get_current arch/x86/include/asm/current.h:15 [inline]
write_comp_data kernel/kcov.c:226 [inline]
__sanitizer_cov_trace_const_cmp4+0xc/0x80 kernel/kcov.c:293
number+0x9d/0xf70 lib/vsprintf.c:460
vsnprintf+0x10fe/0x1a00 lib/vsprintf.c:2877
kvasprintf+0xf2/0x180 lib/kasprintf.c:29
kasprintf+0xd1/0x120 lib/kasprintf.c:59
dvb_create_tsout_entity+0x191/0x390 drivers/media/dvb-core/dvbdev.c:285
dvb_create_media_entity drivers/media/dvb-core/dvbdev.c:322 [inline]
dvb_register_media_device drivers/media/dvb-core/dvbdev.c:416 [inline]
dvb_register_device+0xf1e/0x21b0 drivers/media/dvb-core/dvbdev.c:567
dvb_dmxdev_init+0x2c5/0x420 drivers/media/dvb-core/dmxdev.c:1440
dvb_usb_adapter_dvb_init+0x8f2/0xd70 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:192
dvb_usb_adapter_init drivers/media/usb/dvb-usb/dvb-usb-init.c:86 [inline]
dvb_usb_init drivers/media/usb/dvb-usb/dvb-usb-init.c:186 [inline]
dvb_usb_device_init+0x1acf/0x23f0 drivers/media/usb/dvb-usb/dvb-usb-init.c:310
m920x_probe+0x240/0xe90 drivers/media/usb/dvb-usb/m920x.c:845
usb_probe_interface+0x5a0/0xaf0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x284/0xc80 drivers/base/dd.c:595
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:755
driver_probe_device+0x4f/0x420 drivers/base/dd.c:785
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907
bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429
__device_attach+0x29b/0x460 drivers/base/dd.c:979
bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
device_add+0xa00/0xfb0 drivers/base/core.c:3412
usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2165
usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
usb_probe_device+0x139/0x270 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x284/0xc80 drivers/base/dd.c:595
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:755
driver_probe_device+0x4f/0x420 drivers/base/dd.c:785
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907
bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429
__device_attach+0x29b/0x460 drivers/base/dd.c:979
bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
device_add+0xa00/0xfb0 drivers/base/core.c:3412
usb_new_device+0xd53/0x1640 drivers/usb/core/hub.c:2632
hub_port_connect drivers/usb/core/hub.c:5497 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5637 [inline]
port_event drivers/usb/core/hub.c:5799 [inline]
hub_event+0x2dd9/0x5560 drivers/usb/core/hub.c:5881
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
other info that might help us debug this:
Chain exists of:
&p->pi_lock --> &port_lock_key --> &tty->write_wait
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&tty->write_wait);
lock(&port_lock_key);
lock(&tty->write_wait);
lock(&p->pi_lock);
*** DEADLOCK ***
9 locks held by kworker/0:2/3157:
#0: ffff88801ba9b138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000dbefd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffff888147d8a220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#2: ffff888147d8a220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1a7/0x5560 drivers/usb/core/hub.c:5827
#3: ffff888023cb8220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#3: ffff888023cb8220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x460 drivers/base/dd.c:954
#4: ffff88807a1c01a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#4: ffff88807a1c01a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x460 drivers/base/dd.c:954
#5: ffffffff8cdb9848 (dvbdev_register_lock){+.+.}-{3:3}, at: dvb_register_device+0x46/0x21b0 drivers/media/dvb-core/dvbdev.c:479
#6: ffff888073ac4b30 (&i->lock){-.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:364 [inline]
#6: ffff888073ac4b30 (&i->lock){-.-.}-{2:2}, at: serial8250_interrupt+0x3e/0x1c0 drivers/tty/serial/8250/8250_core.c:117
#7: ffffffff963d82a0 (&port_lock_key){-.-.}-{2:2}, at: serial8250_handle_irq+0x6c/0x610 drivers/tty/serial/8250/8250_port.c:1895
#8: ffff88807a602528 (&tty->write_wait){-...}-{2:2}, at: __wake_up_common_lock kernel/sched/wait.c:137 [inline]
#8: ffff88807a602528 (&tty->write_wait){-...}-{2:2}, at: __wake_up+0xed/0x180 kernel/sched/wait.c:157
stack backtrace:
CPU: 0 PID: 3157 Comm: kworker/0:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: usb_hub_wq hub_event
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2133
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain kernel/locking/lockdep.c:3788 [inline]
__lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
try_to_wake_up+0x5c/0x1050 kernel/sched/core.c:4049
autoremove_wake_function+0x13/0xf0 kernel/sched/wait.c:416
__wake_up_common+0x2a4/0x4e0 kernel/sched/wait.c:108
__wake_up_common_lock kernel/sched/wait.c:138 [inline]
__wake_up+0x108/0x180 kernel/sched/wait.c:157
tty_port_default_wakeup+0xa5/0xf0 drivers/tty/tty_port.c:51
serial8250_tx_chars+0x629/0x830 drivers/tty/serial/8250/8250_port.c:1828
serial8250_handle_irq+0x519/0x610 drivers/tty/serial/8250/8250_port.c:1924
serial8250_default_handle_irq+0xb4/0x1a0 drivers/tty/serial/8250/8250_port.c:1941
serial8250_interrupt+0x9b/0x1c0 drivers/tty/serial/8250/8250_core.c:127
__handle_irq_event_percpu+0x291/0x9b0 kernel/irq/handle.c:156
handle_irq_event_percpu kernel/irq/handle.c:196 [inline]
handle_irq_event+0xa5/0x220 kernel/irq/handle.c:213
handle_edge_irq+0x243/0xb20 kernel/irq/chip.c:819
generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
handle_irq arch/x86/kernel/irq.c:233 [inline]
__common_interrupt+0xd7/0x1e0 arch/x86/kernel/irq.c:252
common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:242
asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:667
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:172 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:227 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0xc/0x80 kernel/kcov.c:293
Code: 44 02 08 03 00 00 00 4a 89 7c 02 10 4a 89 74 02 18 4a 89 44 02 20 48 ff c1 48 89 0a c3 90 48 8b 04 24 65 48 8b 0d 44 a0 8a 7e <65> 8b 15 45 a0 8a 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75
RSP: 0018:ffffc9000dbee638 EFLAGS: 00000246
RAX: ffffffff83fdfced RBX: 0000000000000000 RCX: ffff88802af71dc0
RDX: ffffc90003661000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000dbee760 R08: ffff88802af71dc0 R09: 0000000000000012
R10: 0000000000000012 R11: 0000000000000002 R12: ffff888022720bd1
R13: ffff0a01ffffff10 R14: ffff888022720bcd R15: 00000000ffff0a01
number+0x9d/0xf70 lib/vsprintf.c:460
vsnprintf+0x10fe/0x1a00 lib/vsprintf.c:2877
kvasprintf+0xf2/0x180 lib/kasprintf.c:29
kasprintf+0xd1/0x120 lib/kasprintf.c:59
dvb_create_tsout_entity+0x191/0x390 drivers/media/dvb-core/dvbdev.c:285
dvb_create_media_entity drivers/media/dvb-core/dvbdev.c:322 [inline]
dvb_register_media_device drivers/media/dvb-core/dvbdev.c:416 [inline]
dvb_register_device+0xf1e/0x21b0 drivers/media/dvb-core/dvbdev.c:567
dvb_dmxdev_init+0x2c5/0x420 drivers/media/dvb-core/dmxdev.c:1440
dvb_usb_adapter_dvb_init+0x8f2/0xd70 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:192
dvb_usb_adapter_init drivers/media/usb/dvb-usb/dvb-usb-init.c:86 [inline]
dvb_usb_init drivers/media/usb/dvb-usb/dvb-usb-init.c:186 [inline]
dvb_usb_device_init+0x1acf/0x23f0 drivers/media/usb/dvb-usb/dvb-usb-init.c:310
m920x_probe+0x240/0xe90 drivers/media/usb/dvb-usb/m920x.c:845
usb_probe_interface+0x5a0/0xaf0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x284/0xc80 drivers/base/dd.c:595
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:755
driver_probe_device+0x4f/0x420 drivers/base/dd.c:785
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907
bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429
__device_attach+0x29b/0x460 drivers/base/dd.c:979
bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
device_add+0xa00/0xfb0 drivers/base/core.c:3412
usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2165
usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
usb_probe_device+0x139/0x270 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x284/0xc80 drivers/base/dd.c:595
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:755
driver_probe_device+0x4f/0x420 drivers/base/dd.c:785
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907
bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429
__device_attach+0x29b/0x460 drivers/base/dd.c:979
bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
device_add+0xa00/0xfb0 drivers/base/core.c:3412
usb_new_device+0xd53/0x1640 drivers/usb/core/hub.c:2632
hub_port_connect drivers/usb/core/hub.c:5497 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5637 [inline]
port_event drivers/usb/core/hub.c:5799 [inline]
hub_event+0x2dd9/0x5560 drivers/usb/core/hub.c:5881
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
vkms_vblank_simulate: vblank timer overrun
----------------
Code disassembly (best guess):
0: 44 02 08 add (%rax),%r9b
3: 03 00 add (%rax),%eax
5: 00 00 add %al,(%rax)
7: 4a 89 7c 02 10 mov %rdi,0x10(%rdx,%r8,1)
c: 4a 89 74 02 18 mov %rsi,0x18(%rdx,%r8,1)
11: 4a 89 44 02 20 mov %rax,0x20(%rdx,%r8,1)
16: 48 ff c1 inc %rcx
19: 48 89 0a mov %rcx,(%rdx)
1c: c3 ret
1d: 90 nop
1e: 48 8b 04 24 mov (%rsp),%rax
22: 65 48 8b 0d 44 a0 8a mov %gs:0x7e8aa044(%rip),%rcx # 0x7e8aa06e
29: 7e
* 2a: 65 8b 15 45 a0 8a 7e mov %gs:0x7e8aa045(%rip),%edx # 0x7e8aa076 <-- trapping instruction
31: 81 e2 00 01 ff 00 and $0xff0100,%edx
37: 74 11 je 0x4a
39: 81 fa 00 01 00 00 cmp $0x100,%edx
3f: 75 .byte 0x75