INFO: task kworker/1:2:975 blocked for more than 143 seconds.
Not tainted 6.15.0-rc3-syzkaller-00076-ge72e9e693307 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:2 state:D stack:22696 pid:975 tgid:975 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: events rfkill_sync_work
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b33/0x51f0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
__mutex_lock_common kernel/locking/mutex.c:678 [inline]
__mutex_lock+0x805/0x10c0 kernel/locking/mutex.c:746
device_lock include/linux/device.h:922 [inline]
nfc_dev_down net/nfc/core.c:143 [inline]
nfc_rfkill_set_block+0x50/0x310 net/nfc/core.c:179
rfkill_set_block+0x1f1/0x440 net/rfkill/core.c:346
rfkill_sync net/rfkill/core.c:379 [inline]
rfkill_sync_work+0x12c/0x220 net/rfkill/core.c:1056
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd50 kernel/workqueue.c:3400
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task udevd:5200 blocked for more than 143 seconds.
Not tainted 6.15.0-rc3-syzkaller-00076-ge72e9e693307 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:22600 pid:5200 tgid:5200 ppid:1 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b33/0x51f0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
__mutex_lock_common kernel/locking/mutex.c:678 [inline]
__mutex_lock+0x805/0x10c0 kernel/locking/mutex.c:746
device_lock include/linux/device.h:922 [inline]
uevent_show+0x17d/0x340 drivers/base/core.c:2730
dev_attr_show+0x55/0xc0 drivers/base/core.c:2424
sysfs_kf_seq_show+0x32b/0x4a0 fs/sysfs/file.c:65
seq_read_iter+0x461/0xda0 fs/seq_file.c:230
new_sync_read fs/read_write.c:489 [inline]
vfs_read+0x9a0/0xb90 fs/read_write.c:570
ksys_read+0x19d/0x2d0 fs/read_write.c:713
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9079516b6a
RSP: 002b:00007fff3b574628 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000556b0d2fa730 RCX: 00007f9079516b6a
RDX: 0000000000001000 RSI: 0000556b0d325dc0 RDI: 000000000000000c
RBP: 0000556b0d2fa730 R08: 000000000000000c R09: 0000000000000000
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000003fff R14: 00007fff3b574b08 R15: 000000000000000a
INFO: task kworker/1:5:5894 blocked for more than 143 seconds.
Not tainted 6.15.0-rc3-syzkaller-00076-ge72e9e693307 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:5 state:D stack:24040 pid:5894 tgid:5894 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: events rfkill_global_led_trigger_worker
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b33/0x51f0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
__mutex_lock_common kernel/locking/mutex.c:678 [inline]
__mutex_lock+0x805/0x10c0 kernel/locking/mutex.c:746
rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd50 kernel/workqueue.c:3400
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task syz.7.424:9929 blocked for more than 144 seconds.
Not tainted 6.15.0-rc3-syzkaller-00076-ge72e9e693307 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.424 state:D stack:24936 pid:9929 tgid:9929 ppid:7042 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b33/0x51f0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
schedule_timeout+0xb1/0x2b0 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion+0x32f/0x600 kernel/sched/completion.c:148
__flush_work+0xa48/0xc60 kernel/workqueue.c:4244
__cancel_work_sync+0xbc/0x110 kernel/workqueue.c:4364
rfkill_unregister+0x96/0x230 net/rfkill/core.c:1139
nfc_unregister_device+0x96/0x2a0 net/nfc/core.c:1167
virtual_ncidev_close+0x56/0x90 drivers/nfc/virtual_ncidev.c:172
__fput+0x3e9/0x9f0 fs/file_table.c:465
task_work_run+0x251/0x310 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218
do_syscall_64+0x100/0x210 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa6f4d8e969
RSP: 002b:00007ffe8ca5bf58 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000004fa9d RCX: 00007fa6f4d8e969
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fa6f4fb7ba0 R08: 0000000000000001 R09: 0000000e8ca5c24f
R10: 00007fa6f4c00000 R11: 0000000000000246 R12: 00007fa6f4fb5fac
R13: 00007fa6f4fb5fa0 R14: ffffffffffffffff R15: 00007ffe8ca5c070
INFO: task syz-executor:10312 blocked for more than 144 seconds.
Not tainted 6.15.0-rc3-syzkaller-00076-ge72e9e693307 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:27080 pid:10312 tgid:10312 ppid:1 task_flags:0x400040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b33/0x51f0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
__mutex_lock_common kernel/locking/mutex.c:678 [inline]
__mutex_lock+0x805/0x10c0 kernel/locking/mutex.c:746
rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
hci_register_dev+0x407/0x8b0 net/bluetooth/hci_core.c:2597
__vhci_create_device drivers/bluetooth/hci_vhci.c:429 [inline]
vhci_create_device+0x38b/0x6e0 drivers/bluetooth/hci_vhci.c:471
vhci_get_user drivers/bluetooth/hci_vhci.c:528 [inline]
vhci_write+0x3c8/0x4a0 drivers/bluetooth/hci_vhci.c:608
new_sync_write fs/read_write.c:591 [inline]
vfs_write+0x70f/0xd10 fs/read_write.c:684
ksys_write+0x19d/0x2d0 fs/read_write.c:736
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5e80f8d3e0
RSP: 002b:00007ffd55139dc8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f5e80f8d3e0
RDX: 0000000000000002 RSI: 00007ffd55139dda RDI: 00000000000000ca
RBP: 00007f5e811b6738 R08: 0000000000000000 R09: 00007f5e81ced6c0
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764
4 locks held by kworker/1:2/975:
#0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc90003977c60 ((work_completion)(&rfkill->sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003977c60 ((work_completion)(&rfkill->sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_sync_work+0x23/0x220 net/rfkill/core.c:1055
#3: ffff888060d84100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#3: ffff888060d84100 (&dev->mutex){....}-{4:4}, at: nfc_dev_down net/nfc/core.c:143 [inline]
#3: ffff888060d84100 (&dev->mutex){....}-{4:4}, at: nfc_rfkill_set_block+0x50/0x310 net/nfc/core.c:179
4 locks held by udevd/5200:
#0: ffff888058e9bc30 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb4/0xda0 fs/seq_file.c:182
#1: ffff888024693088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154
#2: ffff8880458aa968 (kn->active#5){.+.+}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155
#3: ffff888060d84100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#3: ffff888060d84100 (&dev->mutex){....}-{4:4}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2730
2 locks held by getty/5585:
#0: ffff8880322630a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5844:
#0: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_unregister+0xd0/0x230 net/rfkill/core.c:1145
3 locks held by kworker/1:5/5894:
#0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc900042afc60 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900042afc60 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182
1 lock held by syz-executor/6796:
#0: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_unregister+0xd0/0x230 net/rfkill/core.c:1145
1 lock held by syz-executor/7234:
#0: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_unregister+0xd0/0x230 net/rfkill/core.c:1145
1 lock held by syz-executor/7787:
#0: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_unregister+0xd0/0x230 net/rfkill/core.c:1145
1 lock held by syz.7.424/9929:
#0: ffff888060d84100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#0: ffff888060d84100 (&dev->mutex){....}-{4:4}, at: nfc_unregister_device+0x63/0x2a0 net/nfc/core.c:1165
2 locks held by syz-executor/10312:
#0: ffff88805e080118 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/10827:
#0: ffff88807b577918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/11245:
#0: ffff888058cc5118 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/11269:
#0: ffff888060eef918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/11271:
#0: ffff88805d5de118 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/11274:
#0: ffff88807aa85918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/11284:
#0: ffff88807ed3e918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/11293:
#0: ffff88805f404918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/11295:
#0: ffff888058cb1918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/11297:
#0: ffff88807c895918 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/11299:
#0: ffff88807bb8e118 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
2 locks held by syz-executor/11308:
#0: ffff88807c5dd118 (&data->open_mutex){+.+.}-{4:4}, at: vhci_create_device+0x34/0x6e0 drivers/bluetooth/hci_vhci.c:470
#1: ffffffff903c6848 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x34/0x8c0 net/rfkill/core.c:1071
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc3-syzkaller-00076-ge72e9e693307 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:437
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
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: 13 Comm: kworker/u8:1 Not tainted 6.15.0-rc3-syzkaller-00076-ge72e9e693307 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: 0x0 (events_unbound)
RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:217
Code: 08 10 65 93 65 8b 15 b8 53 a2 11 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 3c 16 00 00 00 74 2c 8b 91 18 16 00 00 <83> fa 02 75 21 48 8b 91 20 16 00 00 48 8b 32 48 8d 7e 01 8b 89 1c
RSP: 0018:ffffc90000127098 EFLAGS: 00000046
RAX: ffffffff8161c2bd RBX: ffff8880b863a4b0 RCX: ffff88801d6d8000
RDX: 0000000000000000 RSI: ffffffff8e4c80fe RDI: 0000000000000000
RBP: ffffc900001271a0 R08: ffffffff8161c2f1 R09: fffff52000024e2c
R10: dffffc0000000000 R11: fffff52000024e2c R12: ffffc90000127120
R13: dffffc0000000000 R14: ffffffff93651020 R15: 1ffff92000024e20
FS: 0000000000000000(0000) GS:ffff8881250cf000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559afc7daf48 CR3: 000000000eb38000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
sched_clock+0xd/0x70 arch/x86/kernel/tsc.c:284
sched_clock_cpu+0x77/0x4d0 kernel/sched/clock.c:394
update_rq_clock+0x107/0x9e0 kernel/sched/core.c:814
sched_balance_rq+0x50fa/0x8b50 kernel/sched/fair.c:11803
sched_balance_newidle+0x74d/0x11c0 kernel/sched/fair.c:12851
pick_next_task_fair+0x40/0xb80 kernel/sched/fair.c:8938
__pick_next_task+0xdd/0x400 kernel/sched/core.c:6032
pick_next_task kernel/sched/core.c:6117 [inline]
__schedule+0x897/0x51f0 kernel/sched/core.c:6720
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
worker_thread+0xa37/0xd50 kernel/workqueue.c:3415
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245