INFO: task udevd:15272 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:26216 pid:15272 tgid:15272 ppid:4983 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7376
io_schedule+0x7f/0xd0 kernel/sched/core.c:8220
folio_wait_bit_common+0x836/0xbc0 mm/filemap.c:1329
folio_put_wait_locked mm/filemap.c:1498 [inline]
do_read_cache_folio+0x1ac/0x590 mm/filemap.c:4138
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:793
bdev_open+0x324/0xd70 block/bdev.c:1002
blkdev_open+0x461/0x600 block/fops.c:674
do_dentry_open+0x816/0x1380 fs/open.c:996
vfs_open+0x3b/0x340 fs/open.c:1101
do_open fs/namei.c:4837 [inline]
path_openat+0x1443/0x1d60 fs/namei.c:5000
do_file_open+0x23e/0x4a0 fs/namei.c:5029
do_sys_openat2+0x115/0x200 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_openat fs/open.c:1439 [inline]
__se_sys_openat fs/open.c:1434 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1434
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8cca4a7407
RSP: 002b:00007fffb690a4a0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f8ccab93880 RCX: 00007f8cca4a7407
RDX: 00000000000a0800 RSI: 000056458032b480 RDI: ffffffffffffff9c
RBP: 000056458030d910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000564580365180
R13: 000056458031b190 R14: 0000000000000000 R15: 0000564580365180
Showing all locks held in the system:
locks held by khungtaskd/32: 1, last CPU#1:
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by getty/5369: 2, on CPU#0:
#0: ffff8880360d00a0 (&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+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by kworker/0:9/14433: 5, last CPU#0:
#0: ffff88801b069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801b069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801b069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#0: ffff88801b069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#1: ffffc9000d3dfc40 ((work_completion)(&(&tbl->gc_work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc9000d3dfc40 ((work_completion)(&(&tbl->gc_work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc9000d3dfc40 ((work_completion)(&(&tbl->gc_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#1: ffffc9000d3dfc40 ((work_completion)(&(&tbl->gc_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#2: ffffffff90385798 (&tbl->lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:353 [inline]
#2: ffffffff90385798 (&tbl->lock){+.-.}-{3:3}, at: neigh_periodic_work+0xc43/0xe40 net/core/neighbour.c:1037
#3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: neigh_periodic_work+0x41d/0xe40 net/core/neighbour.c:1004
#4: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#4: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#4: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: __neigh_notify+0x29/0x310 net/core/neighbour.c:3580
locks held by udevd/15272: 1, on CPU#0:
#0: ffff8880269d8350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:990
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [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+0x38b/0x480 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: 14433 Comm: kworker/0:9 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Workqueue: events_power_efficient neigh_periodic_work
RIP: 0010:check_preemption_disabled+0x1/0xd0 lib/smp_processor_id.c:13
Code: 20 ad 6d 8c 48 c7 c6 60 ad 6d 8c eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 <41> 57 41 56 53 65 8b 05 1b 8d ae 07 65 48 8b 0d eb 8c ae 07 85 c9
RSP: 0018:ffffc9000d3df3a8 EFLAGS: 00000046
RAX: 144e24c52308859d RBX: 0000000000000206 RCX: 0000000000000000
RDX: ffffc9000d3df501 RSI: ffffffff8e69f4bd RDI: ffffffff8c6dad80
RBP: ffff88807e730c78 R08: ffffc9000d3dff38 R09: 0000000000000000
R10: ffffc9000d3df518 R11: fffff52001a7bea5 R12: 0000000000000005
R13: 0000000000000005 R14: ffffffff8ed5c8a0 R15: ffff88807e730000
FS: 0000000000000000(0000) GS:ffff888124cc7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1c106904c0 CR3: 000000000eb48000 CR4: 00000000003526f0
Call Trace:
lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline]
lock_release+0x263/0x3c0 kernel/locking/lockdep.c:5966
rcu_lock_release include/linux/rcupdate.h:319 [inline]
rcu_read_unlock include/linux/rcupdate.h:880 [inline]
class_rcu_destructor include/linux/rcupdate.h:1216 [inline]
unwind_next_frame+0x1baa/0x2550 arch/x86/kernel/unwind_orc.c:709
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:264 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:296
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2748 [inline]
slab_free mm/slub.c:6508 [inline]
kmem_cache_free+0x182/0x650 mm/slub.c:6635
netlink_broadcast_filtered+0xd9d/0xea0 net/netlink/af_netlink.c:1560
nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
nlmsg_multicast include/net/netlink.h:1184 [inline]
nlmsg_notify+0xe3/0x1a0 net/netlink/af_netlink.c:2618
__neigh_notify+0x1ae/0x310 net/core/neighbour.c:3593
neigh_notify net/core/neighbour.c:3604 [inline]
neigh_cleanup_and_release+0xae/0x2b0 net/core/neighbour.c:119
neigh_periodic_work+0xb4a/0xe40 net/core/neighbour.c:1026
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
kthread+0x38b/0x480 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