INFO: task udevd:1196 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:20096 pid:1196 tgid:1196 ppid:5193 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7183
__schedule_loop kernel/sched/core.c:7262 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7277
io_schedule+0x7f/0xd0 kernel/sched/core.c:8104
folio_wait_bit_common+0x6d8/0xbc0 mm/filemap.c:1323
folio_put_wait_locked mm/filemap.c:1492 [inline]
do_read_cache_folio+0x1ad/0x590 mm/filemap.c:4088
read_mapping_folio include/linux/pagemap.h:1017 [inline]
read_part_sector+0xb6/0x2b0 block/partitions/core.c:724
adfspart_check_POWERTEC+0x9a/0x7a0 block/partitions/acorn.c:450
check_partition block/partitions/core.c:143 [inline]
blk_add_partitions block/partitions/core.c:591 [inline]
bdev_disk_changed+0x817/0x1770 block/partitions/core.c:695
blkdev_get_whole+0x380/0x510 block/bdev.c:756
bdev_open+0x31e/0xd30 block/bdev.c:965
blkdev_open+0x470/0x610 block/fops.c:697
do_dentry_open+0x785/0x14e0 fs/open.c:947
vfs_open+0x3b/0x340 fs/open.c:1079
do_open fs/namei.c:4699 [inline]
path_openat+0x2e08/0x3860 fs/namei.c:4858
do_file_open+0x23e/0x4a0 fs/namei.c:4887
do_sys_openat2+0x113/0x200 fs/open.c:1364
do_sys_open fs/open.c:1370 [inline]
__do_sys_openat fs/open.c:1386 [inline]
__se_sys_openat fs/open.c:1381 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1381
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f79e2aa7407
RSP: 002b:00007ffe4ee1ea00 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f79e324e880 RCX: 00007f79e2aa7407
RDX: 00000000000a0800 RSI: 0000558e14368aa0 RDI: ffffffffffffff9c
RBP: 0000558e14357910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000558e14361840
R13: 0000558e14365190 R14: 0000000000000000 R15: 0000558e14361840
Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
1 lock held by khungtaskd/30:
#0: ffffffff8e95d020 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e95d020 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e95d020 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5582:
#0: ffff888036b810a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
1 lock held by udevd/1196:
#0: ffff8880275b4350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:953
2 locks held by syz.2.20081/18437:
#0: ffffffff8fdc01c8 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:575
#1: ffffffff8e963328 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e963328 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
1 lock held by syz.4.20086/18450:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfaa/0x1000 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
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: 15030 Comm: kworker/0:10 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: events free_ipc
RIP: 0010:__bfs kernel/locking/lockdep.c:-1 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x1968/0x2cf0 kernel/locking/lockdep.c:5237
Code: 89 c1 81 e1 ff 0f 00 00 89 0d d8 f6 a4 14 2b 05 ce f6 a4 14 25 ff 0f 00 00 39 05 8f f6 a3 12 73 06 89 05 87 f6 a3 12 48 8b 02 <48> 89 df 4c 39 e8 0f 84 2c fe ff ff 4c 89 60 30 48 8b 00 4c 39 e8
RSP: 0018:ffffc90004caf2f8 EFLAGS: 00000002
RAX: ffffffff96e72d58 RBX: 00000000000003fd RCX: 0000000000000392
RDX: ffffffff96e72b28 RSI: ffff88802bc38ca8 RDI: 00000000000003fd
RBP: cd8e5a636224f02c R08: ffffc90004caf2c0 R09: 0000000000000020
R10: dffffc0000000000 R11: ffffffff81a1e3d0 R12: ffffffff96e72b98
R13: ffffffff93f07ba8 R14: ffff88802bc38000 R15: 0000000000000391
FS: 0000000000000000(0000) GS:ffff888125245000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000051a030 CR3: 00000000b1720000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
debug_object_deactivate+0x6c/0x3a0 lib/debugobjects.c:890
debug_hrtimer_deactivate kernel/time/hrtimer.c:490 [inline]
remove_hrtimer kernel/time/hrtimer.c:1190 [inline]
hrtimer_try_to_cancel+0x34e/0x670 kernel/time/hrtimer.c:1527
update_curr_dl_se+0x32c/0xe80 kernel/sched/deadline.c:1491
update_curr+0x1fa/0x4e0 kernel/sched/fair.c:1412
enqueue_entity kernel/sched/fair.c:5505 [inline]
enqueue_task_fair+0x442/0x2aa0 kernel/sched/fair.c:7223
enqueue_task+0x75/0x410 kernel/sched/core.c:2160
activate_task kernel/sched/core.c:2200 [inline]
ttwu_do_activate+0x1cc/0x660 kernel/sched/core.c:3720
ttwu_queue kernel/sched/core.c:3973 [inline]
try_to_wake_up+0x724/0x1380 kernel/sched/core.c:4297
kthread_queue_work+0xff/0x180 kernel/kthread.c:1207
synchronize_rcu_expedited_queue_work kernel/rcu/tree_exp.h:498 [inline]
synchronize_rcu_expedited+0x48e/0x770 kernel/rcu/tree_exp.h:971
free_ipc+0xb5/0x1d0 ipc/namespace.c:180
process_one_work kernel/workqueue.c:3288 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3371
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3452
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245