INFO: task kworker/0:6:17968 blocked for more than 143 seconds.
Not tainted 6.12.0-rc6-syzkaller-00153-g237d4e0f4113 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:6 state:D stack:22528 pid:17968 tgid:17968 ppid:2 flags:0x00004000
Workqueue: events console_callback
Call Trace:
context_switch kernel/sched/core.c:5328 [inline]
__schedule+0x1042/0x34b0 kernel/sched/core.c:6690
__schedule_loop kernel/sched/core.c:6767 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6782
schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591
___down_common+0x2d7/0x460 kernel/locking/semaphore.c:225
__down_common kernel/locking/semaphore.c:246 [inline]
__down+0x20/0x30 kernel/locking/semaphore.c:254
down+0x74/0xa0 kernel/locking/semaphore.c:63
console_lock+0x5b/0xa0 kernel/printk/printk.c:2808
console_callback+0x63/0x4c0 drivers/tty/vt/vt.c:3120
process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff88ebb140
(rcu_read_lock
){....}-{1:2}
, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720
5 locks held by kworker/0:2/41:
6 locks held by kworker/1:1/64:
5 locks held by kworker/1:2/2825:
2 locks held by getty/2920:
#0: ffff8881120420a0 (&tty->ldisc_sem){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
4 locks held by udevd/16146:
#0:
ffff88811c3559e0 (&p->lock){+.+.}-{3:3}
, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182
#1: ffff888108b16c88
(&of->mutex#2){+.+.}-{3:3}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154
#2: ffff8881077d8968
(kn->active
#3){++++}-{0:0}
, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155
#3: ffff8881087cb190
(&dev->mutex
){....}-{3:3}
, at: device_lock include/linux/device.h:1014 [inline]
, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2736
2 locks held by kworker/0:6/17968:
#0: ffff888100080948 ((wq_completion)events
){+.+.}-{0:0}
, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204
#1: ffffc9000493fd80 (console_work
){+.+.}-{0:0}
, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205
5 locks held by kworker/1:6/18841:
7 locks held by kworker/0:14/24359:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc6-syzkaller-00153-g237d4e0f4113 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
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:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
watchdog+0xf0c/0x1240 kernel/hung_task.c:379
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 24359 Comm: kworker/0:14 Not tainted 6.12.0-rc6-syzkaller-00153-g237d4e0f4113 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: usb_hub_wq hub_event
RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:413
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 11 e5 0d ff eb a0 e8 9a e5 0d
RSP: 0018:ffffc9000795f370 EFLAGS: 00000002
RAX: 0000000000000035 RBX: 00000000000003f8 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: ffffffff82a096d5 RDI: ffffffff936336a0
RBP: ffffffff93633660 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000035 R14: ffffffff82a09670 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556165f4a8 CR3: 0000000123d16000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
serial_out drivers/tty/serial/8250/8250.h:142 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3322 [inline]
serial8250_console_write+0xf9e/0x17c0 drivers/tty/serial/8250/8250_port.c:3393
console_emit_next_record kernel/printk/printk.c:3092 [inline]
console_flush_all+0x800/0xc60 kernel/printk/printk.c:3180
__console_flush_and_unlock kernel/printk/printk.c:3239 [inline]
console_unlock+0xd9/0x210 kernel/printk/printk.c:3279
vprintk_emit+0x424/0x6f0 kernel/printk/printk.c:2407
dev_vprintk_emit drivers/base/core.c:4942 [inline]
dev_printk_emit+0xfb/0x140 drivers/base/core.c:4953
__dev_printk+0xf5/0x270 drivers/base/core.c:4965
_dev_info+0xe5/0x120 drivers/base/core.c:5011
hub_port_init+0xce6/0x3ab0 drivers/usb/core/hub.c:4950
hub_port_connect drivers/usb/core/hub.c:5450 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5661 [inline]
port_event drivers/usb/core/hub.c:5821 [inline]
hub_event+0x2c16/0x4f40 drivers/usb/core/hub.c:5903
process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244