INFO: task syz.4.16:520 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.16 state:D stack:0 pid:520 tgid:520 ppid:476 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_timeout+0xb2/0x3a0 kernel/time/timer.c:2595
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common+0x359/0x630 kernel/sched/completion.c:127
wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
__flush_work+0x6d2/0xac0 kernel/workqueue.c:4233
__cancel_work_sync kernel/workqueue.c:4354 [inline]
cancel_work_sync+0xac/0xe0 kernel/workqueue.c:4391
uhid_dev_destroy drivers/hid/uhid.c:584 [inline]
uhid_char_release+0xa7/0x600 drivers/hid/uhid.c:662
__fput+0x1fe/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e0/0x250 kernel/task_work.c:240
resume_user_mode_work+0x36/0x50 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x64/0xb0 kernel/entry/common.c:218
do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f0580b8e929
RSP: 002b:00007ffef31d47f8 EFLAGS: 00000246
ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000000c5f9 RCX: 00007f0580b8e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f0580db7ba0 R08: 0000000000000001 R09: 00000003f31d4aef
R10: 00007f0580a00000 R11: 0000000000000246 R12: 00007f0580db5fac
R13: 00007f0580db5fa0 R14: ffffffffffffffff R15: 00007ffef31d4910
INFO: task syz.2.21:524 blocked for more than 124 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.21 state:D
stack:0 pid:524 tgid:524 ppid:480 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_timeout+0xb2/0x3a0 kernel/time/timer.c:2595
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common+0x359/0x630 kernel/sched/completion.c:127
wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
__flush_work+0x6d2/0xac0 kernel/workqueue.c:4233
__cancel_work_sync kernel/workqueue.c:4354 [inline]
cancel_work_sync+0xac/0xe0 kernel/workqueue.c:4391
uhid_dev_destroy drivers/hid/uhid.c:584 [inline]
uhid_char_release+0xa7/0x600 drivers/hid/uhid.c:662
__fput+0x1fe/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e0/0x250 kernel/task_work.c:240
resume_user_mode_work+0x36/0x50 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x64/0xb0 kernel/entry/common.c:218
do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f10f538e929
RSP: 002b:00007fffea05b868 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000000c634 RCX: 00007f10f538e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f10f55b7ba0 R08: 0000000000000001 R09: 00000003ea05bb5f
R10: 00007f10f5200000 R11: 0000000000000246 R12: 00007f10f55b5fac
R13: 00007f10f55b5fa0 R14: ffffffffffffffff R15: 00007fffea05b980
INFO: task syz.3.22:528 blocked for more than 125 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.22 state:D
stack:0 pid:528 tgid:528 ppid:481 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_timeout+0xb2/0x3a0 kernel/time/timer.c:2595
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common+0x359/0x630 kernel/sched/completion.c:127
wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
__flush_work+0x6d2/0xac0 kernel/workqueue.c:4233
__cancel_work_sync kernel/workqueue.c:4354 [inline]
cancel_work_sync+0xac/0xe0 kernel/workqueue.c:4391
uhid_dev_destroy drivers/hid/uhid.c:584 [inline]
uhid_char_release+0xa7/0x600 drivers/hid/uhid.c:662
__fput+0x1fe/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e0/0x250 kernel/task_work.c:240
resume_user_mode_work+0x36/0x50 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x64/0xb0 kernel/entry/common.c:218
do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f157758e929
RSP: 002b:00007ffe894c5658 EFLAGS: 00000246
ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000000c664 RCX: 00007f157758e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f15777b7ba0 R08: 0000000000000001 R09: 00000003894c594f
R10: 00007f1577400000 R11: 0000000000000246 R12: 00007f15777b5fac
R13: 00007f15777b5fa0 R14: ffffffffffffffff R15: 00007ffe894c5770
INFO: task syz.1.23:533 blocked for more than 126 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.23 state:D
stack:0 pid:533 tgid:533 ppid:478 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_timeout+0xb2/0x3a0 kernel/time/timer.c:2595
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common+0x359/0x630 kernel/sched/completion.c:127
wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
__flush_work+0x6d2/0xac0 kernel/workqueue.c:4233
__cancel_work_sync kernel/workqueue.c:4354 [inline]
cancel_work_sync+0xac/0xe0 kernel/workqueue.c:4391
uhid_dev_destroy drivers/hid/uhid.c:584 [inline]
uhid_char_release+0xa7/0x600 drivers/hid/uhid.c:662
__fput+0x1fe/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e0/0x250 kernel/task_work.c:240
resume_user_mode_work+0x36/0x50 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x64/0xb0 kernel/entry/common.c:218
do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f9fa338e929
RSP: 002b:00007ffe44fc6c08 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000000c691 RCX: 00007f9fa338e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f9fa35b7ba0 R08: 0000000000000001 R09: 0000000344fc6eff
R10: 00007f9fa3200000 R11: 0000000000000246 R12: 00007f9fa35b5fac
R13: 00007f9fa35b5fa0 R14: ffffffffffffffff R15: 00007ffe44fc6d20
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 95167fa7b47a7fb5a2b4cf844ce00148e80797b6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
dump_stack+0x19/0x20 lib/dump_stack.c:129
nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
watchdog+0xd8f/0xed0 kernel/hung_task.c:423
kthread+0x2ca/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 380 Comm: kworker/1:3 Not tainted syzkaller #0 95167fa7b47a7fb5a2b4cf844ce00148e80797b6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events uhid_device_add_worker
RIP: 0010:io_serial_out+0x85/0xd0 drivers/tty/serial/8250/8250_port.c:413
Code: fe 44 89 e1 41 d3 e6 49 83 c7 08 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 d4 78 c3 fe 45 03 37 89 d8 44 89 f2 ee <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 44 89 e1 80 e1 07
RSP: 0018:ffffc900010aede8 EFLAGS: 00000002
RAX: 000000000000005b RBX: 000000000000005b RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffc900010aee10 R08: ffff888107e8c107 R09: 1ffff11020fd1820
R10: 0000000000000000 R11: ffffffff8318d4e0 R12: 0000000000000000
R13: dffffc0000000000 R14: 00000000000003f8 R15: ffffffff889f3e28
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555619764a8 CR3: 000000010b722000 CR4: 00000000003526b0
Call Trace:
serial_out drivers/tty/serial/8250/8250.h:142 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline]
serial8250_console_write+0x166d/0x2130 drivers/tty/serial/8250/8250_port.c:3421
univ8250_console_write+0x6f/0xb0 drivers/tty/serial/8250/8250_core.c:396
console_emit_next_record kernel/printk/printk.c:3152 [inline]
console_flush_all+0x5e6/0xaa0 kernel/printk/printk.c:3240
__console_flush_and_unlock kernel/printk/printk.c:3299 [inline]
console_unlock+0xe9/0x270 kernel/printk/printk.c:3339
vprintk_emit+0x27c/0x640 kernel/printk/printk.c:2463
dev_vprintk_emit+0x33b/0x400 drivers/base/core.c:4962
dev_printk_emit+0xe1/0x130 drivers/base/core.c:4973
__dev_printk+0x17f/0x1b0 drivers/base/core.c:4985
_dev_warn+0x10b/0x160 drivers/base/core.c:5029
hid_parser_main+0x84b/0xdc0 drivers/hid/hid-core.c:632
hid_open_report+0x868/0x1110 drivers/hid/hid-core.c:1278
hid_parse include/linux/hid.h:1138 [inline]
hid_generic_probe+0x42/0x90 drivers/hid/hid-generic.c:66
__hid_device_probe drivers/hid/hid-core.c:2711 [inline]
hid_device_probe+0x2c1/0x5d0 drivers/hid/hid-core.c:2748
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x2d6/0x890 drivers/base/dd.c:657
__driver_probe_device+0x198/0x280 drivers/base/dd.c:799
driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829
__device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957
bus_for_each_drv+0x260/0x2f0 drivers/base/bus.c:459
__device_attach+0x2bd/0x3a0 drivers/base/dd.c:1029
device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078
bus_probe_device+0x18b/0x270 drivers/base/bus.c:534
device_add+0x80c/0xc00 drivers/base/core.c:3692
hid_add_device+0x39b/0x560 drivers/hid/hid-core.c:2894
uhid_device_add_worker+0x49/0xf0 drivers/hid/uhid.c:73
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3319
worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
kthread+0x2ca/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244