INFO: task udevd:5245 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:udevd state:D stack:23824 pid:5245 tgid:5245 ppid:2861 flags:0x00004002
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_preempt_disabled+0x13/0x30 kernel/sched/core.c:6839
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752
device_lock include/linux/device.h:1014 [inline]
uevent_show+0x188/0x3b0 drivers/base/core.c:2736
dev_attr_show+0x53/0xe0 drivers/base/core.c:2430
sysfs_kf_seq_show+0x23e/0x410 fs/sysfs/file.c:59
seq_read_iter+0x4f4/0x12b0 fs/seq_file.c:230
kernfs_fop_read_iter+0x414/0x580 fs/kernfs/file.c:279
new_sync_read fs/read_write.c:488 [inline]
vfs_read+0x87f/0xbe0 fs/read_write.c:569
ksys_read+0x12f/0x260 fs/read_write.c:712
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ffb19da2b6a
RSP: 002b:00007ffde73aab48 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000563ffbd7fe30 RCX: 00007ffb19da2b6a
RDX: 0000000000001000 RSI: 0000563ffbda6150 RDI: 0000000000000008
RBP: 0000563ffbd7fe30 R08: 0000000000000008 R09: 0000000000000004
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000003fff R14: 00007ffde73ab028 R15: 000000000000000a
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]
#0: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720
2 locks held by getty/2919:
#0: ffff88811225d0a0 (&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/5245:
#0: ffff888102767668 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182
#1: ffff88811bcad888 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154
#2: ffff88811a64c3c8 (kn->active){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155
#3: ffff888123e3f190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#3: ffff888123e3f190 (&dev->mutex){....}-{3:3}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2736
5 locks held by kworker/1:4/5274:
#0: ffff8881066cc148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204
#1: ffffc900020ffd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205
#2: ffff888108f94190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#2: ffff888108f94190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849
#3: ffff8881f593d6d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:598 [inline]
#3: ffff8881f593d6d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1505 [inline]
#3: ffff8881f593d6d8 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1804 [inline]
#3: ffff8881f593d6d8 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x293/0x34b0 kernel/sched/core.c:6589
#4: ffffffff9355e608 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x199/0x540 lib/debugobjects.c:708
6 locks held by kworker/1:5/5301:
5 locks held by kworker/0:5/18345:
=============================================
NMI backtrace for cpu 0
CPU: 0 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 19094 Comm: kworker/1:0 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: events dvb_usb_read_remote_control
RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:407
Code: 5b b5 fe 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 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c c3 cc cc cc cc e8 58 e4 0d ff eb a2 e8 e1 e4
RSP: 0018:ffffc9000290f7c8 EFLAGS: 00000006
RAX: dffffc0000000005 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: ffffffff82a09790 RDI: ffffffff936336a0
RBP: ffffffff93633660 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff93633660 R14: ffffffff936336b0 R15: 000000000000002f
FS: 0000000000000000(0000) GS:ffff8881f5900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe4a4cfe28 CR3: 000000011659c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
serial_port_in include/linux/serial_core.h:787 [inline]
serial8250_console_write+0x22d/0x17c0 drivers/tty/serial/8250/8250_port.c:3357
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
vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:68
_printk+0xc8/0x100 kernel/printk/printk.c:2432
m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline]
m920x_rc_core_query+0x2d7/0x500 drivers/media/usb/dvb-usb/m920x.c:229
dvb_usb_read_remote_control+0xda/0x1c0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:261
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