INFO: task kworker/0:3:3268 blocked for more than 144 seconds.
Not tainted 5.4.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:3 D23664 3268 2 0x80004000
Workqueue: usb_hub_wq hub_event
Call Trace:
schedule+0xca/0x250 kernel/sched/core.c:4136
schedule_timeout+0x682/0xb20 kernel/time/timer.c:1871
do_wait_for_common kernel/sched/completion.c:83 [inline]
__wait_for_common kernel/sched/completion.c:104 [inline]
wait_for_common kernel/sched/completion.c:115 [inline]
wait_for_completion+0x26f/0x3c0 kernel/sched/completion.c:136
kthread_stop+0x10c/0x610 kernel/kthread.c:559
dvb_ca_en50221_release+0x91/0x200 drivers/media/dvb-core/dvb_ca_en50221.c:1934
tt3650_ci_uninit drivers/media/usb/dvb-usb/pctv452e.c:364 [inline]
pctv452e_usb_disconnect+0xb0/0xf0 drivers/media/usb/dvb-usb/pctv452e.c:1061
usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423
__device_release_driver drivers/base/dd.c:1134 [inline]
device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1165
bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:532
device_del+0x420/0xb20 drivers/base/core.c:2376
usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237
usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2200
hub_port_connect drivers/usb/core/hub.c:5035 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5324 [inline]
port_event drivers/usb/core/hub.c:5470 [inline]
hub_event+0x16f2/0x3800 drivers/usb/core/hub.c:5552
process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
worker_thread+0x96/0xe20 kernel/workqueue.c:2415
kthread+0x318/0x420 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Showing all locks held in the system:
6 locks held by kworker/0:0/5:
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240
#1: ffff8881da1dfdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244
#2: ffff8881d518e200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
#2: ffff8881d518e200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498
#3: ffff8881d51b0520 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2997 [inline]
#3: ffff8881d51b0520 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5115 [inline]
#3: ffff8881d51b0520 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5324 [inline]
#3: ffff8881d51b0520 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5470 [inline]
#3: ffff8881d51b0520 (&port_dev->status_lock){+.+.}, at: hub_event+0x1c06/0x3800 drivers/usb/core/hub.c:5552
#4: ffff8881d5113260 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b6/0x2d30 drivers/usb/core/hub.c:4539
#5: ffffffff871e6fa8 (ehci_cf_port_reset_rwsem){.+.+}, at: hub_port_reset+0x17b/0x1460 drivers/usb/core/hub.c:2859
1 lock held by khungtaskd/23:
#0: ffffffff86cfe8a0 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:5335
1 lock held by rsyslogd/1602:
#0: ffff8881d37d3c60 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:801
2 locks held by getty/1693:
#0: ffff8881d1591090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
#1: ffffc900004812e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1694:
#0: ffff8881d1aca090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
#1: ffffc900004652e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1695:
#0: ffff8881d1926090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
#1: ffffc900004752e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1696:
#0: ffff8881d24cc090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
#1: ffffc9000045d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1697:
#0: ffff8881d1592090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
#1: ffffc900004852e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1698:
#0: ffff8881d1925090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
#1: ffffc900004712e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1699:
#0: ffff8881d2c27090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
#1: ffffc900004552e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
5 locks held by kworker/0:3/3268:
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240
#1: ffff8881d0a27dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244
#2: ffff8881d5167200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
#2: ffff8881d5167200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498
#3: ffff8881cd612200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
#3: ffff8881cd612200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2191
#4: ffff8881cd617190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162
6 locks held by kworker/0:4/3277:
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240
#1: ffff8881afa47dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244
#2: ffff8881d5141200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
#2: ffff8881d5141200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498
#3: ffff8881d991a200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
#3: ffff8881d991a200 (&dev->mutex){....}, at: __device_attach+0x7b/0x360 drivers/base/dd.c:871
#4: ffff8881cd615190 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
#4: ffff8881cd615190 (&dev->mutex){....}, at: __device_attach+0x7b/0x360 drivers/base/dd.c:871
#5: ffff8881ae252120 (zr364xx:1417:(hdl)->_lock){+.+.}, at: v4l2_ctrl_handler_setup drivers/media/v4l2-core/v4l2-ctrls.c:2925 [inline]
#5: ffff8881ae252120 (zr364xx:1417:(hdl)->_lock){+.+.}, at: v4l2_ctrl_handler_setup+0x45/0xa0 drivers/media/v4l2-core/v4l2-ctrls.c:2918
5 locks held by kdvb-ca-2:0/10061:
6 locks held by kworker/0:1/10462:
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240
#1: ffff8881b0337dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244
#2: ffff8881d50ca200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
#2: ffff8881d50ca200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498
#3: ffff8881d50cc520 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2997 [inline]
#3: ffff8881d50cc520 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5115 [inline]
#3: ffff8881d50cc520 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5324 [inline]
#3: ffff8881d50cc520 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5470 [inline]
#3: ffff8881d50cc520 (&port_dev->status_lock){+.+.}, at: hub_event+0x1c06/0x3800 drivers/usb/core/hub.c:5552
#4: ffff8881d549f660 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b6/0x2d30 drivers/usb/core/hub.c:4539
#5: ffffffff871e6fa8 (ehci_cf_port_reset_rwsem){.+.+}, at: hub_port_reset+0x17b/0x1460 drivers/usb/core/hub.c:2859
6 locks held by kworker/0:8/10928:
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline]
#0: ffff8881d8efd128 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240
#1: ffff8881ce82fdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244
#2: ffff8881d51b5200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
#2: ffff8881d51b5200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498
#3: ffff8881d51b7520 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2997 [inline]
#3: ffff8881d51b7520 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5115 [inline]
#3: ffff8881d51b7520 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5324 [inline]
#3: ffff8881d51b7520 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5470 [inline]
#3: ffff8881d51b7520 (&port_dev->status_lock){+.+.}, at: hub_event+0x1c06/0x3800 drivers/usb/core/hub.c:5552
#4: ffff8881d5113560 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b6/0x2d30 drivers/usb/core/hub.c:4539
#5: ffffffff871e6fa8 (ehci_cf_port_reset_rwsem){.+.+}, at: hub_port_reset+0x17b/0x1460 drivers/usb/core/hub.c:2859
2 locks held by syz-executor.5/11909:
#0: ffff8881b22a4860 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:801
#1: ffff8881d2a1ddb0 (&sb->s_type->i_mutex_key#10){++++}, at: inode_lock_shared include/linux/fs.h:801 [inline]
#1: ffff8881d2a1ddb0 (&sb->s_type->i_mutex_key#10){++++}, at: ext4_direct_IO_read fs/ext4/inode.c:3830 [inline]
#1: ffff8881d2a1ddb0 (&sb->s_type->i_mutex_key#10){++++}, at: ext4_direct_IO+0x44d/0x1b90 fs/ext4/inode.c:3869
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 23 Comm: khungtaskd Not tainted 5.4.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xca/0x13e lib/dump_stack.c:113
nmi_cpu_backtrace.cold+0x55/0x96 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x1b0/0x1c7 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
watchdog+0x9a4/0xe50 kernel/hung_task.c:289
kthread+0x318/0x420 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10061 Comm: kdvb-ca-2:0 Not tainted 5.4.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:trace_hrtimer_expire_exit include/trace/events/timer.h:279 [inline]
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1515 [inline]
RIP: 0010:__hrtimer_run_queues+0x878/0xc60 kernel/time/hrtimer.c:1576
Code: e8 ad 4d 0e 00 84 db 0f 84 35 02 00 00 e8 70 4c 0e 00 65 ff 0d d1 14 d2 7e e9 82 f9 ff ff e8 5f 4c 0e 00 65 ff 05 c0 14 d2 7e <48> c7 c0 a8 e2 84 87 48 c1 e8 03 42 80 3c 30 00 0f 85 a9 03 00 00
RSP: 0018:ffff8881db209e30 EFLAGS: 00000002
RAX: ffff8881c8fbc800 RBX: 0000000000000000 RCX: ffffffff812fd4de
RDX: 0000000000010000 RSI: ffffffff812fda01 RDI: 0000000000000001
RBP: ffff8881db225b00 R08: ffff8881c8fbc800 R09: fffffbfff0f0ca21
R10: fffffbfff0f0ca20 R11: ffffffff87865107 R12: ffff8881db225b80
R13: ffff8881b476fdd0 R14: dffffc0000000000 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fba5bff6000 CR3: 00000001ced87000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
hrtimer_interrupt+0x2e8/0x730 kernel/time/hrtimer.c:1638
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
smp_apic_timer_interrupt+0xf5/0x500 arch/x86/kernel/apic/apic.c:1135
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/irqflags.h:85 [inline]
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:1751 [inline]
RIP: 0010:vprintk_emit+0x3cd/0x3e0 kernel/printk/printk.c:1995
Code: 00 83 fb ff 75 d6 e9 db fc ff ff e8 9d 7b 15 00 e8 68 a8 1a 00 41 56 9d e9 b1 fd ff ff e8 8b 7b 15 00 e8 56 a8 1a 00 41 56 9d 2a ff ff ff 0f 1f 40 00 66 2e 0f 1f 84 00 00 00 00 00 55 48 89
RSP: 0018:ffff8881d905faa8 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000007 RBX: 0000000000000200 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8881c8fbd04c
RBP: ffff8881d905faf0 R08: ffff8881c8fbc800 R09: fffffbfff11aafc0
R10: fffffbfff11aafbf R11: ffffffff88d57dff R12: 0000000000000027
R13: ffff8881da27c800 R14: 0000000000000293 R15: 0000000000000000
vprintk_func+0x75/0x113 kernel/printk/printk_safe.c:386
printk+0xba/0xed kernel/printk/printk.c:2056
dvb_usb_generic_rw.cold+0x33/0x56 drivers/media/usb/dvb-usb/dvb-usb-urb.c:36
tt3650_ci_msg+0x1b1/0x2f0 drivers/media/usb/dvb-usb/pctv452e.c:126
tt3650_ci_msg_locked+0x83/0xb0 drivers/media/usb/dvb-usb/pctv452e.c:157
tt3650_ci_poll_slot_status+0x90/0x110 drivers/media/usb/dvb-usb/pctv452e.c:333
dvb_ca_en50221_check_camstatus+0x102/0x330 drivers/media/dvb-core/dvb_ca_en50221.c:234
dvb_ca_en50221_thread_state_machine drivers/media/dvb-core/dvb_ca_en50221.c:1128 [inline]
dvb_ca_en50221_thread+0x26b/0x13e0 drivers/media/dvb-core/dvb_ca_en50221.c:1317
kthread+0x318/0x420 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352