INFO: task udevd:6274 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:24232 pid:6274  ppid:5143   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6701
 schedule+0xbd/0x170 kernel/sched/core.c:6775
 io_schedule+0x80/0xd0 kernel/sched/core.c:9024
 folio_wait_bit_common+0x881/0xfa0 mm/filemap.c:1329
 folio_put_wait_locked mm/filemap.c:1493 [inline]
 do_read_cache_folio+0x1c0/0x7f0 mm/filemap.c:3791
 read_mapping_folio include/linux/pagemap.h:898 [inline]
 read_part_sector+0xd2/0x350 block/partitions/core.c:718
 adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454
 check_partition block/partitions/core.c:138 [inline]
 blk_add_partitions block/partitions/core.c:600 [inline]
 bdev_disk_changed+0x755/0x1450 block/partitions/core.c:689
 blkdev_get_whole+0x30d/0x390 block/bdev.c:668
 blkdev_get_by_dev+0x3a9/0x610 block/bdev.c:810
 blkdev_open+0x14e/0x360 block/fops.c:589
 do_dentry_open+0x880/0x14b0 fs/open.c:929
 do_open fs/namei.c:3683 [inline]
 path_openat+0x284f/0x3270 fs/namei.c:3844
 do_filp_open+0x1f2/0x430 fs/namei.c:3871
 do_sys_openat2+0x134/0x1d0 fs/open.c:1422
 do_sys_open fs/open.c:1437 [inline]
 __do_sys_openat fs/open.c:1453 [inline]
 __se_sys_openat fs/open.c:1448 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1448
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f92556a7407
RSP: 002b:00007fffc5be4d90 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f9255d44880 RCX: 00007f92556a7407
RDX: 00000000000a0800 RSI: 000055eee9b48900 RDI: ffffffffffffff9c
RBP: 000055eee9b37910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055eee9b5b990
R13: 000055eee9b4f410 R14: 0000000000000000 R15: 000055eee9b5b990
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6635
3 locks held by kworker/u4:10/3433:
1 lock held by udevd/5143:
 #0: ffff888019e45948 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_dop_revalidate+0xc8/0x570 fs/kernfs/dir.c:1159
1 lock held by sshd-session/5763:
2 locks held by syz-executor/5775:
3 locks held by kworker/0:6/5838:
1 lock held by udevd/6241:
1 lock held by udevd/6274:
 #0: ffff888021da34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x11b/0x610 block/bdev.c:801
2 locks held by syz-executor/7817:
2 locks held by syz-executor/7833:
4 locks held by syz-executor/7956:
2 locks held by getty/9579:
 #0: ffff88802d33a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000455d2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
2 locks held by kworker/u4:3/12877:
2 locks held by syz-executor/12958:
3 locks held by syz-executor/12983:
 #0: ffffffff8e3d0988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
 #0: ffffffff8e3d0988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7ed/0xf90 net/core/rtnetlink.c:6481
 #1: ffff8880b8f3c258 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559
 #2: ffff8880b8f3c258 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559
2 locks held by syz.3.2689/12990:

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xf59/0xfa0 kernel/hung_task.c:379
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 12894 Comm: kworker/0:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events nsim_dev_hwstats_traffic_work
RIP: 0010:__sanitizer_cov_trace_switch+0x58/0xe0 kernel/kcov.c:345
Code: 48 8b 06 48 85 c0 0f 84 a4 00 00 00 41 57 41 56 41 54 53 48 8d 4c 09 01 48 8b 54 24 20 65 4c 8b 05 9d 27 7c 7e 45 31 c9 eb 08 <49> ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d 8b 27 7c 7e 41
RSP: 0018:ffffc9000ba4f2a8 EFLAGS: 00000093
RAX: 0000000000000020 RBX: 0000000000000009 RCX: 0000000000000005
RDX: ffffffff81895e15 RSI: ffffffff8d17b560 RDI: 0000000000000009
RBP: 00000000000009b8 R08: ffff888029541e00 R09: 000000000000000e
R10: 000000000000000e R11: 0000000000000000 R12: dffffc0000000000
R13: f800000000000000 R14: ffff8880186405f8 R15: 000000000004ca89
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f62ee957e20 CR3: 000000006097b000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 rb_event_length+0x45/0x3f0 kernel/trace/ring_buffer.c:198
 check_buffer+0x542/0x950 kernel/trace/ring_buffer.c:3494
 __rb_reserve_next+0x4d9/0xd00 kernel/trace/ring_buffer.c:3627
 rb_reserve_next_event kernel/trace/ring_buffer.c:3762 [inline]
 ring_buffer_lock_reserve+0xae1/0xed0 kernel/trace/ring_buffer.c:3821
 __trace_buffer_lock_reserve kernel/trace/trace.c:996 [inline]
 trace_event_buffer_lock_reserve+0x1d2/0x6f0 kernel/trace/trace.c:2905
 trace_event_buffer_reserve+0x2ac/0x3d0 kernel/trace/trace_events.c:661
 do_trace_event_raw_event_lock include/trace/events/lock.h:50 [inline]
 trace_event_raw_event_lock+0x11e/0x240 include/trace/events/lock.h:50
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0x866/0x8c0 kernel/locking/lockdep.c:5767
 debug_objects_fill_pool+0xcc/0x790 lib/debugobjects.c:655
 debug_object_assert_init+0x66/0x300 lib/debugobjects.c:940
 debug_timer_assert_init kernel/time/timer.c:792 [inline]
 debug_assert_init kernel/time/timer.c:837 [inline]
 __mod_timer+0x55/0xd60 kernel/time/timer.c:1020
 queue_delayed_work_on+0x131/0x200 kernel/workqueue.c:2010
 process_one_work kernel/workqueue.c:2657 [inline]
 process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>