INFO: task udevd:8538 blocked in I/O wait 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:23976 pid:8538 tgid:8538 ppid:4991 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
io_schedule+0x7f/0xd0 kernel/sched/core.c:8154
folio_wait_bit_common+0x836/0xbc0 mm/filemap.c:1323
folio_put_wait_locked mm/filemap.c:1492 [inline]
do_read_cache_folio+0x1ac/0x590 mm/filemap.c:4122
read_mapping_folio include/linux/pagemap.h:1015 [inline]
read_part_sector+0xb6/0x2b0 block/partitions/core.c:724
adfspart_check_POWERTEC+0x9a/0x7a0 block/partitions/acorn.c:451
check_partition block/partitions/core.c:143 [inline]
blk_add_partitions block/partitions/core.c:591 [inline]
bdev_disk_changed+0x851/0x17a0 block/partitions/core.c:695
blkdev_get_whole+0x372/0x510 block/bdev.c:751
bdev_open+0x324/0xd70 block/bdev.c:960
blkdev_open+0x461/0x600 block/fops.c:672
do_dentry_open+0x816/0x1380 fs/open.c:947
vfs_open+0x3b/0x340 fs/open.c:1052
do_open fs/namei.c:4700 [inline]
path_openat+0x2e44/0x3830 fs/namei.c:4859
do_file_open+0x23e/0x4a0 fs/namei.c:4888
do_sys_openat2+0x115/0x200 fs/open.c:1368
do_sys_open fs/open.c:1374 [inline]
__do_sys_openat fs/open.c:1390 [inline]
__se_sys_openat fs/open.c:1385 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1385
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f42306a7407
RSP: 002b:00007ffe23d9a480 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f4230dc4880 RCX: 00007f42306a7407
RDX: 00000000000a0800 RSI: 000055db1707e3d0 RDI: ffffffffffffff9c
RBP: 000055db17074910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055db17087e20
R13: 000055db17082190 R14: 0000000000000000 R15: 000055db17087e20
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8eb59c20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8eb59c20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8eb59c20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5380:
#0: ffff8880324f90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
1 lock held by udevd/8538:
#0: ffff88802735d350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:948
3 locks held by kworker/u8:20/10999:
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc9000d8a7c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc9000d8a7c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#2: ffffffff9002bb40 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
1 lock held by udevd/13416:
#0: ffff888027555350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:948
2 locks held by syz.0.4509/22024:
#0: ffffffff9002bb40 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:641 [inline]
#0: ffffffff9002bb40 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3506
#1: ffffffff8eb5ff28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8eb5ff28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
1 lock held by syz.4.4512/22039:
#0: ffffffff9002bb40 (rtnl_mutex){+.+.}-{4:4}, at: bpf_xdp_link_attach+0x120/0x990 net/core/dev.c:10677
1 lock held by syz.4.4512/22040:
#0: ffffffff9002bb40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff9002bb40 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x767/0xc00 net/core/rtnetlink.c:7082
=============================================
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 05/09/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
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: 22046 Comm: rm Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x36/0x90 kernel/kcov.c:300
Code: 38 eb a5 11 65 8b 0d 59 eb a5 11 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 24 17 00 00 00 74 52 8b 8a f8 16 00 00 <83> f9 03 75 47 48 8b 8a 00 17 00 00 44 8b 8a fc 16 00 00 49 c1 e1
RSP: 0018:ffffc900025578a8 EFLAGS: 00000246
RAX: ffffffff84879708 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: ffff8880319c8000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffff888032376810 R08: ffff888032376837 R09: 1ffff1100646ed06
R10: dffffc0000000000 R11: ffffed100646ed07 R12: ffff888032376830
R13: 000000000000002f R14: 000000000000002e R15: 0000000000000001
FS: 00007f18dda0bc80(0000) GS:ffff888124f5a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f18ddd4637e CR3: 0000000028da0000 CR4: 00000000003526f0
Call Trace:
variable_test_bit arch/x86/include/asm/bitops.h:222 [inline]
arch_test_bit arch/x86/include/asm/bitops.h:233 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
tomoyo_check_acl+0x2f8/0x400 security/tomoyo/domain.c:184
tomoyo_path_permission+0x1a6/0x3b0 security/tomoyo/file.c:591
tomoyo_path_perm+0x3f3/0x560 security/tomoyo/file.c:843
security_inode_getattr+0x12b/0x310 security/security.c:1895
vfs_getattr+0x23/0x70 fs/stat.c:259
vfs_statx_path+0x2b/0x230 fs/stat.c:299
vfs_statx+0x12e/0x200 fs/stat.c:356
vfs_fstatat+0x11b/0x170 fs/stat.c:373
__do_sys_newfstatat fs/stat.c:538 [inline]
__se_sys_newfstatat fs/stat.c:532 [inline]
__x64_sys_newfstatat+0x151/0x200 fs/stat.c:532
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f18ddbc5b0a
Code: 48 8b 15 f1 f2 0d 00 f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 b9 f2 0d 00 f7
RSP: 002b:00007ffceea43f48 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007ffceea45dd2 RCX: 00007f18ddbc5b0a
RDX: 00007ffceea43f58 RSI: 00007ffceea45dd2 RDI: 00000000ffffff9c
RBP: 0000000000000008 R08: 00007ffceea45dd2 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f18ddd599cc R14: 00007f18dddb5000 R15: 0000555b25e77d98