INFO: task kworker/0:2:1118 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:2 state:D stack:19800 pid:1118 tgid:1118 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0xeb1/0x4220 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7008 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 class_mutex_constructor include/linux/mutex.h:253 [inline] usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950 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:2268 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+0x6c3/0xcb0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task kworker/1:2:2813 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:2 state:D stack:21488 pid:2813 tgid:2813 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0xeb1/0x4220 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7008 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 class_mutex_constructor include/linux/mutex.h:253 [inline] usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950 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:2268 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+0x6c3/0xcb0 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: 6 locks held by kworker/0:0/9: #0: ffff888105e90948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc9000009fd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffff88810cb181e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #2: ffff88810cb181e0 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff8881339811e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #3: ffff8881339811e0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #4: ffff8881339401a8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #4: ffff8881339401a8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #5: ffffffff8aa21188 (register_mutex#3){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #5: ffffffff8aa21188 (register_mutex#3){+.+.}-{4:4}, at: usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950 8 locks held by kworker/0:1/10: 1 lock held by khungtaskd/30: #0: ffffffff896de760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 6 locks held by kworker/0:2/1118: #0: ffff888105e90948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc90002edfd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffff88810c7981e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #2: ffff88810c7981e0 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff88811b2c81e0 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #4: ffff888119a361a8 ( &dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] ){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #5: ffffffff8aa21188 ( register_mutex #3 ){+.+.}-{4:4} , at: class_mutex_constructor include/linux/mutex.h:253 [inline] , at: usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950 6 locks held by kworker/1:2/2813: #0: ffff888105e90948 ( (wq_completion)usb_hub_wq ){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc9000590fd18 ( (work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffff88810cf081e0 ( &dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] &dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff8881192e01e0 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #4: ffff88811ec8c1a8 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #5: ffffffff8aa21188 ( register_mutex #3 ){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] ){+.+.}-{4:4}, at: usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950 2 locks held by getty/2916: #0: ffff888115e3b0a0 ( &tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 ( &ldata->atomic_read_lock ){+.+.}-{4:4} , at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 4 locks held by udevd/5223: #0: ffff88811963e2f0 ( &p->lock ){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff88811df56888 ( &of->mutex #2 ){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff88811ba9ac38 ( kn->active #21 ){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] ){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff8881192e01e0 ( &dev->mutex ){....}-{4:4} , at: device_lock_interruptible include/linux/device.h:954 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 4 locks held by udevd/5234: #0: ffff88811dd6c0a0 ( &p->lock ){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff88811e183c88 ( &of->mutex #2 ){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff888113d07f08 ( kn->active #21 ){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] ){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88811b2c81e0 ( &dev->mutex ){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:954 [inline] ){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 6 locks held by kworker/1:4/5238: #0: ffff888105e90948 ( (wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc90003297d18 ( (work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffff88810cb681e0 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff8881367c11e0 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #4: ffff88811ff1c1a8 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #5: ffffffff8aa21188 ( register_mutex #3 ){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] ){+.+.}-{4:4}, at: usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950 4 locks held by udevd/5882: #0: ffff88811b084668 ( &p->lock ){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff888113e21088 ( &of->mutex #2 ){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff888112712e18 ( kn->active #21 ){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] ){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88811a3ad1e0 ( &dev->mutex ){....}-{4:4} , at: device_lock_interruptible include/linux/device.h:954 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 4 locks held by udevd/6951: #0: ffff888113428668 ( &p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff888118e21488 ( &of->mutex #2 ){+.+.}-{4:4} , at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff888114904b48 ( kn->active #21){++++}-{0:0} , at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] , at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff8881339811e0 (&dev->mutex){....}-{4:4} , at: device_lock_interruptible include/linux/device.h:954 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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+0x6c3/0xcb0 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: 10 Comm: kworker/0:1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: usb_hub_wq hub_event RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:408 Code: 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1c 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d c3 cc cc cc cc e8 e1 78 f5 fe eb a0 e8 6a 79 f5 RSP: 0018:ffffc900000ae350 EFLAGS: 00000002 RAX: 0000000000000020 RBX: 00000000000003f8 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff83208635 RDI: ffffffff941b8be0 RBP: ffffffff941b8ba0 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000020 R14: 0000000000000010 R15: ffffffff832085d0 FS: 0000000000000000(0000) GS:ffff8882686c9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555569ed0908 CR3: 00000001230c4000 CR4: 00000000003506f0 Call Trace: serial_port_out include/linux/serial_core.h:811 [inline] serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3217 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3279 [inline] serial8250_console_write+0xde8/0x1900 drivers/tty/serial/8250/8250_port.c:3357 console_emit_next_record kernel/printk/printk.c:3183 [inline] console_flush_one_record+0x790/0xe50 kernel/printk/printk.c:3269 console_flush_all kernel/printk/printk.c:3343 [inline] __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0x103/0x260 kernel/printk/printk.c:3413 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479 dev_vprintk_emit+0x394/0x3e0 drivers/base/core.c:4915 dev_printk_emit+0xd2/0x10d drivers/base/core.c:4926 __dev_printk+0xcb/0x100 drivers/base/core.c:4938 _dev_err+0xef/0x127 drivers/base/core.c:4981 parse_uac2_sample_rate_range.cold+0x100/0x135 sound/usb/format.c:468 parse_audio_format_rates_v2v3+0x2fe/0xf70 sound/usb/format.c:689 parse_audio_format_ii sound/usb/format.c:847 [inline] snd_usb_parse_audio_format.cold+0x48c/0x4cc sound/usb/format.c:868 snd_usb_get_audioformat_uac12 sound/usb/stream.c:856 [inline] __snd_usb_parse_audio_interface+0xa85/0x4710 sound/usb/stream.c:1201 snd_usb_parse_audio_interface+0x81/0x110 sound/usb/stream.c:1282 create_standard_audio_quirk+0x6b/0x120 sound/usb/quirks.c:101 snd_usb_create_quirk sound/usb/quirks.c:541 [inline] create_composite_quirk+0x257/0x510 sound/usb/quirks.c:49 snd_usb_create_quirk+0xad/0xf0 sound/usb/quirks.c:541 usb_audio_probe+0x992/0x3a90 sound/usb/card.c:1023 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:2268 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+0x6c3/0xcb0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245