INFO: task kworker/1:3:5934 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:3 state:D
stack:22872 pid:5934 tgid:5934 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: events console_callback
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
___down_common kernel/locking/semaphore.c:268 [inline]
__down_common+0x33e/0x750 kernel/locking/semaphore.c:293
down+0xaa/0xe0 kernel/locking/semaphore.c:100
console_lock+0x58/0x90 kernel/printk/printk.c:2843
class_console_lock_constructor include/linux/console.h:737 [inline]
console_callback+0x69/0x440 drivers/tty/vt/vt.c:3256
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1760 kernel/workqueue.c:3340
worker_thread+0xa57/0xfc0 kernel/workqueue.c:3421
kthread+0x711/0x890 kernel/kthread.c:463
ret_from_fork+0x595/0xb20 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
INFO: task kworker/1:3:5934 blocked on a semaphore likely last held by task udevd:6409
task:udevd state:S
stack:25448 pid:6409 tgid:6409 ppid:5199 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_hrtimeout_range_clock+0x1c5/0x2f0 kernel/time/sleep_timeout.c:207
ep_poll fs/eventpoll.c:2028 [inline]
do_epoll_wait+0xca7/0xf30 fs/eventpoll.c:2461
__do_sys_epoll_wait fs/eventpoll.c:2469 [inline]
__se_sys_epoll_wait fs/eventpoll.c:2464 [inline]
__x64_sys_epoll_wait+0x1be/0x210 fs/eventpoll.c:2464
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x8a/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fda882a7407
RSP: 002b:00007ffeb447fc70 EFLAGS: 00000202
ORIG_RAX: 00000000000000e8
RAX: ffffffffffffffda RBX: 00007fda88aa9880 RCX: 00007fda882a7407
RDX: 0000000000000004 RSI: 00007ffeb447fd00 RDI: 0000000000000004
RBP: 000056464e4ea910 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000202 R12: 000056464e502e00
R13: 00007ffeb447fd00 R14: 0000000000000000 R15: 000056464e502e00
Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
#0:
ffff88813fe69948
(
(wq_completion)events_unbound
#2
){+.+.}-{0:0}
, at: process_one_work kernel/workqueue.c:3232 [inline]
, at: process_scheduled_works+0x9b4/0x1760 kernel/workqueue.c:3340
#1:
ffffc90000127b60
(
(linkwatch_work).work
){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1760 kernel/workqueue.c:3340
#2:
ffffffff8f0c7148
(rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
1 lock held by khungtaskd/31:
#0:
ffffffff8dd3fba0 (rcu_read_lock){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
6 locks held by kworker/u8:4/70:
#0:
ffff88801aadf148
(
(wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
(wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1760 kernel/workqueue.c:3340
#1: ffffc9000218fb60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000218fb60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1760 kernel/workqueue.c:3340
#2:
ffffffff8f0ba090
(
pernet_ops_rwsem
){++++}-{4:4}
, at: cleanup_net+0xf7/0x860 net/core/net_namespace.c:670
#3:
ffff888078c880e8
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:914 [inline]
, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506
#4:
ffff888021ebf250
(
&devlink->lock_key
#7
){+.+.}-{4:4}
, at: devl_lock net/devlink/core.c:276 [inline]
, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506
#5:
ffffffff8dd455c0
(
rcu_state.barrier_mutex
){+.+.}-{4:4}
, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3816
6 locks held by udevd/5199:
2 locks held by getty/5590:
#0:
ffff8880336ed0a0
(
&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1:
ffffc9000331e2f0
(
&ldata->atomic_read_lock
){+.+.}-{4:4}
, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by kworker/1:3/5934:
#0:
ffff88813fe55948
(
(wq_completion)events
){+.+.}-{0:0}
, at: process_one_work kernel/workqueue.c:3232 [inline]
, at: process_scheduled_works+0x9b4/0x1760 kernel/workqueue.c:3340
#1:
ffffc900036c7b60
(
console_work
){+.+.}-{0:0}
, at: process_one_work kernel/workqueue.c:3233 [inline]
, at: process_scheduled_works+0x9ef/0x1760 kernel/workqueue.c:3340
1 lock held by syz.1.91/7018:
#0:
ffff888142bef358
(
&disk->open_mutex
){+.+.}-{4:4}
, at: bdev_release+0x1a9/0x650 block/bdev.c:1145
3 locks held by syz-executor/7030:
#0:
ffffffff8e85f568
(
&ops->srcu
#2
){.+.+}-{0:0}
, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1:
ffffffff8f0c7148
(
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
, at: rtnl_newlink+0x8ec/0x1c80 net/core/rtnetlink.c:4071
#2:
ffffffff8dd456f8
(
rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:956
3 locks held by syz.2.95/7039:
#0:
ffff8880246f1448
(
&lo->lo_mutex
){+.+.}-{4:4}, at: loop_set_status+0xa2/0xd60 drivers/block/loop.c:1236
#1:
ffff8880246db008 (&q->q_usage_counter(io)#19){++++}-{0:0}, at: blk_mq_freeze_queue include/linux/blk-mq.h:954 [inline]
ffff8880246db008 (&q->q_usage_counter(io)#19){++++}-{0:0}, at: loop_set_status+0x2e4/0xd60 drivers/block/loop.c:1252
#2:
ffff8880246db040
(&q->q_usage_counter(queue)
#3
){+.+.}-{0:0}
, at: blk_mq_freeze_queue include/linux/blk-mq.h:954 [inline]
, at: loop_set_status+0x2e4/0xd60 drivers/block/loop.c:1252
1 lock held by syz.4.96/7041:
#0:
ffffffff8dd456f8
(
rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:956
3 locks held by syz.4.96/7042:
#0: ffff8880246f7448 (&lo->lo_mutex){+.+.}-{4:4}, at: loop_set_status+0xa2/0xd60 drivers/block/loop.c:1236
#1: ffff8880246dc318 (&q->q_usage_counter(io)#21){++++}-{0:0}, at: blk_mq_freeze_queue include/linux/blk-mq.h:954 [inline]
#1: ffff8880246dc318 (&q->q_usage_counter(io)#21){++++}-{0:0}, at: loop_set_status+0x2e4/0xd60 drivers/block/loop.c:1252
#2: ffff8880246dc350 (&q->q_usage_counter(queue)#5){+.+.}-{0:0}, at: blk_mq_freeze_queue include/linux/blk-mq.h:954 [inline]
#2: ffff8880246dc350 (&q->q_usage_counter(queue)#5){+.+.}-{0:0}, at: loop_set_status+0x2e4/0xd60 drivers/block/loop.c:1252
6 locks held by syz.1.97/7045:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0x16db/0x1720 kernel/hung_task.c:495
kthread+0x711/0x890 kernel/kthread.c:463
ret_from_fork+0x595/0xb20 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5199 Comm: udevd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_switch+0x8f/0x130 kernel/kcov.c:351
Code: 00 00 00 41 57 41 56 41 54 53 48 8b 54 24 20 65 4c 8b 04 25 08 50 4b 92 45 31 c9 eb 08 49 ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 <65> 44 8b 1d 79 bc 8a 10 41 81 e3 00 01 ff 00 74 13 41 81 fb 00 01
RSP: 0018:ffffc90003356c28 EFLAGS: 00000202
RAX: 0000000000000008 RBX: dffffc0000000000 RCX: 0000000000000001
RDX: ffffffff8b298df8 RSI: ffffffff8f439180 RDI: 0000000000000001
RBP: ffffffff8b4ba945 R08: ffff88807dbd5b80 R09: 0000000000000006
R10: 0000000000000006 R11: 0000000000000000 R12: ffffc90003356d40
R13: ffffc90003356f21 R14: 0000000000000801 R15: ffffffff8b4ba941
FS: 00007fda88aa9880(0000) GS:ffff88812636b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556fff35c8 CR3: 000000007cf64000 CR4: 00000000003526f0
Call Trace:
vsnprintf+0x118/0xee0 lib/vsprintf.c:2891
sprintf+0xd9/0x120 lib/vsprintf.c:3110
print_time kernel/printk/printk.c:1357 [inline]
info_print_prefix+0x155/0x310 kernel/printk/printk.c:1383
record_print_text+0x154/0x420 kernel/printk/printk.c:1432
printk_get_next_message+0x26d/0x7b0 kernel/printk/printk.c:3018
console_emit_next_record kernel/printk/printk.c:3083 [inline]
console_flush_one_record kernel/printk/printk.c:3215 [inline]
console_flush_all+0x514/0xb50 kernel/printk/printk.c:3289
__console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
console_unlock+0xbb/0x190 kernel/printk/printk.c:3359
vprintk_emit+0x4f8/0x5f0 kernel/printk/printk.c:2426
_printk+0xcf/0x120 kernel/printk/printk.c:2451
blk_add_partition block/partitions/core.c:540 [inline]
blk_add_partitions block/partitions/core.c:633 [inline]
bdev_disk_changed+0xc7b/0x14b0 block/partitions/core.c:693
blkdev_get_whole+0x380/0x510 block/bdev.c:765
bdev_open+0x31e/0xd30 block/bdev.c:974
blkdev_open+0x457/0x600 block/fops.c:702
do_dentry_open+0x7cc/0x1420 fs/open.c:962
vfs_open+0x3b/0x340 fs/open.c:1094
do_open fs/namei.c:4628 [inline]
path_openat+0x340a/0x3dd0 fs/namei.c:4787
do_filp_open+0x1fa/0x410 fs/namei.c:4814
do_sys_openat2+0x121/0x200 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1447
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x8a/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fda882a7407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffeb447fde0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fda88aa9880 RCX: 00007fda882a7407
RDX: 00000000000a0800 RSI: 000056464e6501b0 RDI: ffffffffffffff9c
RBP: 000056464e5057b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000056464e5051d0
R13: 0000564627277100 R14: 0000000000000000 R15: 00007ffeb4480130