INFO: task syz.4.852:9122 blocked for more than 143 seconds.
Not tainted 6.16.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.852 state:D stack:26808 pid:9122 tgid:9116 ppid:5835 task_flags:0x400640 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6879
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common+0x2ff/0x4e0 kernel/sched/completion.c:116
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264
coredump_wait fs/coredump.c:504 [inline]
do_coredump+0x8fa/0x4f10 fs/coredump.c:686
get_signal+0x22e3/0x26d0 kernel/signal.c:3019
arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f370c24f830
RSP: 002b:00007f370d2783f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000000 RBX: 00007f370c5b6088 RCX: 00007f370c38e929
RDX: 00007f370d278400 RSI: 00007f370d278530 RDI: 000000000000000b
RBP: 00007f370c5b6080 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f370c5b608c
R13: 0000000000000000 R14: 00007ffccae7fed0 R15: 00007ffccae7ffb8
Showing all locks held in the system:
1 lock held by ksoftirqd/0/15:
#0: ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline]
#0: ffff8880b843a2d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599
1 lock held by khungtaskd/31:
#0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770
2 locks held by getty/5589:
#0: ffff888037a620a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xf70/0x12c0 kernel/hung_task.c:470
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
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: 1204 Comm: kworker/0:2 Not tainted 6.16.0-rc6-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events legacy_dvb_usb_read_remote_control
RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:416
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 e9 56 74 2f 06 e8 01 fd c6 fc eb a0 e8 8a fd c6
RSP: 0018:ffffc9000455f628 EFLAGS: 00000002
RAX: 000000000000005b RBX: 00000000000003f8 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: ffffffff855bced5 RDI: ffffffff9b0c72a0
RBP: ffffffff9b0c7260 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 000000000000005b R14: ffffffff9b0c7260 R15: ffffffff855bce70
FS: 0000000000000000(0000) GS:ffff888124713000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000008030 CR3: 000000002ba69000 CR4: 00000000003526f0
DR0: 0000000000000004 DR1: 0000000000000006 DR2: 0000000000000007
DR3: 0000000000001000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
serial_port_out include/linux/serial_core.h:798 [inline]
serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3306 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline]
serial8250_console_write+0xfbf/0x1890 drivers/tty/serial/8250/8250_port.c:3456
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x7fe/0xc60 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xd8/0x210 kernel/printk/printk.c:3325
vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450
_printk+0xc7/0x100 kernel/printk/printk.c:2475
dvb_usb_generic_rw+0x270/0x490 drivers/media/usb/dvb-usb/dvb-usb-urb.c:36
dibusb_rc_query+0x9a/0x110 drivers/media/usb/dvb-usb/dibusb-common.c:386
legacy_dvb_usb_read_remote_control+0x10c/0x4f0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3321 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245