INFO: task udevd:4328 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:25168 pid: 4328 ppid:  3560 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503
 wait_on_page_bit_common+0x83b/0xe50 mm/filemap.c:1356
 wait_on_page_bit mm/filemap.c:1417 [inline]
 wait_on_page_locked include/linux/pagemap.h:688 [inline]
 wait_on_page_read mm/filemap.c:3437 [inline]
 do_read_cache_page+0xb05/0x1030 mm/filemap.c:3480
 read_mapping_page include/linux/pagemap.h:515 [inline]
 read_part_sector+0xd4/0x4f0 block/partitions/core.c:726
 adfspart_check_ICS+0xc3/0xe40 block/partitions/acorn.c:360
 check_partition block/partitions/core.c:148 [inline]
 blk_add_partitions block/partitions/core.c:611 [inline]
 bdev_disk_changed+0x933/0x16c0 block/partitions/core.c:697
 blkdev_get_whole+0x2f9/0x390 block/bdev.c:682
 blkdev_get_by_dev+0x2d0/0xa60 block/bdev.c:827
 blkdev_open+0x12d/0x2c0 block/fops.c:466
 do_dentry_open+0x7ff/0xf80 fs/open.c:826
 do_open fs/namei.c:3616 [inline]
 path_openat+0x26f5/0x2fa0 fs/namei.c:3750
 do_filp_open+0x1e2/0x410 fs/namei.c:3777
 do_sys_openat2+0x150/0x4b0 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0b161ae407
RSP: 002b:00007ffcd24d2aa0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f0b160c0880 RCX: 00007f0b161ae407
RDX: 00000000000a0800 RSI: 0000563139cf82c0 RDI: ffffffffffffff9c
RBP: 0000563139cf0910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000563139d08e00
R13: 0000563139d08410 R14: 0000000000000000 R15: 0000563139d08e00
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:4/1273:
 #0: ffff8880b913a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
 #1: ffff8880b9127888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4fe/0x7d0 kernel/sched/psi.c:891
3 locks held by kworker/0:2/1335:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc90005187d00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
 #2: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
2 locks held by udevd/3560:
 #0: ffff8880203d7518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
 #1: ffff8880204cd468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2071
2 locks held by getty/3945:
 #0: ffff88802b791098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900023ce2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
1 lock held by udevd/4328:
 #0: ffff88802050c518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
4 locks held by syz.2.1863/9724:
 #0: ffff888025d40ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_reset net/bluetooth/hci_core.c:1890 [inline]
 #0: ffff888025d40ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_reset+0x12f/0x660 net/bluetooth/hci_core.c:1942
 #1: ffff888025d40078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_reset net/bluetooth/hci_core.c:1901 [inline]
 #1: ffff888025d40078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_reset+0x17b/0x660 net/bluetooth/hci_core.c:1942
 #2: ffffffff8d582a28 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline]
 #2: ffffffff8d582a28 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa4/0x220 net/bluetooth/hci_conn.c:1622
 #3: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
 #3: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
1 lock held by syz.1.1877/9733:
 #0: ffff8880203d7518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
1 lock held by dhcpcd/9760:

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7457 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:io_serial_in+0x73/0xb0 drivers/tty/serial/8250/8250_port.c:461
Code: e8 e2 9c 29 fd 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 a3 a8 6e fd 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 44 89 f9 80 e1 07 38 c1 7c aa 4c
RSP: 0018:ffffc90002f0f170 EFLAGS: 00000002
RAX: 1ffffffff2cc0100 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: 0000000000000020 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520005e1e24 R12: dffffc0000000000
R13: ffffffff96600aa8 R14: ffffffff96600840 R15: 0000000000000000
FS:  000055557da06500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7dfdd424e0 CR3: 0000000025b4d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 serial_in drivers/tty/serial/8250/8250.h:116 [inline]
 wait_for_xmitr+0xe9/0x260 drivers/tty/serial/8250/8250_port.c:2069
 serial8250_console_putchar+0x1a/0x50 drivers/tty/serial/8250/8250_port.c:3309
 uart_console_write+0xaa/0x100 drivers/tty/serial/serial_core.c:1981
 serial8250_console_write+0xc46/0x1000 drivers/tty/serial/8250/8250_port.c:3386
 call_console_drivers kernel/printk/printk.c:-1 [inline]
 console_unlock+0xb9a/0x1120 kernel/printk/printk.c:2744
 vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274
 _printk+0xda/0x130 kernel/printk/printk.c:2299
 ntfs_printk+0x330/0x3b0 fs/ntfs3/super.c:68
 ntfs_set_state+0x3ca/0x640 fs/ntfs3/fsntfs.c:944
 ni_write_inode+0x72d/0x1080 fs/ntfs3/frecord.c:3336
 ntfs_evict_inode+0x63/0xb0 fs/ntfs3/inode.c:1791
 evict+0x4c9/0x8d0 fs/inode.c:647
 dispose_list fs/inode.c:680 [inline]
 evict_inodes+0x60c/0x6a0 fs/inode.c:734
 generic_shutdown_super+0x93/0x300 fs/super.c:454
 kill_block_super+0x7c/0xe0 fs/super.c:1427
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f4ff96f6897
Code: a2 c7 05 5c ee 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffd5ffe7ae8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f4ff978aef0 RCX: 00007f4ff96f6897
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd5ffe7ba0
RBP: 00007ffd5ffe7ba0 R08: 00007ffd5ffe8ba0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd5ffe8c30
R13: 00007f4ff978aef0 R14: 00000000000401df R15: 00007ffd5ffe8c70
 </TASK>