INFO: task udevd:4234 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:23296 pid: 4234 ppid: 3561 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 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+0x815/0xe00 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:731
adfspart_check_ICS+0xbf/0xe00 block/partitions/acorn.c:360
check_partition block/partitions/core.c:148 [inline]
blk_add_partitions block/partitions/core.c:616 [inline]
bdev_disk_changed+0x917/0x16b0 block/partitions/core.c:702
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:3608 [inline]
path_openat+0x2682/0x2f30 fs/namei.c:3742
do_filp_open+0x1b3/0x3e0 fs/namei.c:3769
do_sys_openat2+0x142/0x4a0 fs/open.c:1253
do_sys_open fs/open.c:1269 [inline]
__do_sys_openat fs/open.c:1285 [inline]
__se_sys_openat fs/open.c:1280 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1280
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: 0033:0x7f9545cbf407
RSP: 002b:00007ffd604e5770 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f9545bd1880 RCX: 00007f9545cbf407
RDX: 00000000000a0800 RSI: 000056098d909bc0 RDI: ffffffffffffff9c
RBP: 000056098d8e7910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000056098d8ef650
R13: 000056098d8ff410 R14: 0000000000000000 R15: 000056098d8ef650
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:2/154:
#0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffff8880b9127888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4d6/0x810 kernel/sched/psi.c:891
4 locks held by kworker/u4:3/1230:
2 locks held by getty/3950:
#0: ffff88802b6cc098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
1 lock held by udevd/4234:
#0: ffff888020044518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
2 locks held by kworker/u4:5/4275:
2 locks held by kworker/u4:6/4312:
#0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc900033ffd00 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
1 lock held by udevd/4342:
3 locks held by kworker/0:11/5546:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90003ecfd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8c1210e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#2: ffffffff8c1210e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845
2 locks held by kworker/0:12/5547:
#0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90003d6fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
5 locks held by kworker/1:20/7225:
2 locks held by udevd/10704:
#0: ffff88801fdcf918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
#1: ffff88801fed0468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 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
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7225 Comm: kworker/1:20 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events_power_efficient gc_worker
RIP: 0010:__lock_acquire+0x108/0x7c60 kernel/locking/lockdep.c:4882
Code: 00 74 29 48 89 d8 48 c1 e8 03 42 80 3c 00 00 74 12 48 89 df e8 d9 34 60 00 49 b8 00 00 00 00 00 fc ff df 48 81 3b 80 bf b2 8f <75> 03 45 31 e4 44 89 bc 24 c8 00 00 00 41 83 fe 01 77 30 44 89 f0
RSP: 0018:ffffc90000dd0800 EFLAGS: 00000083
RAX: 1ffffffff1db8511 RBX: ffffffff8edc2888 RCX: 1ffff920001ba124
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8edc2888
RBP: ffffc90000dd0a50 R08: dffffc0000000000 R09: 0000000000000001
R10: fffffbfff1ad323e R11: 1ffffffff1ad323d R12: 0000000000000001
R13: ffff888023033b80 R14: 0000000000000000 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9545287000 CR3: 00000000295cb000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
do_write_seqcount_begin_nested include/linux/seqlock.h:519 [inline]
do_write_seqcount_begin include/linux/seqlock.h:545 [inline]
update_pvclock_gtod arch/x86/kvm/x86.c:2127 [inline]
pvclock_gtod_notify+0xcb/0x480 arch/x86/kvm/x86.c:8667
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
update_pvclock_gtod kernel/time/timekeeping.c:655 [inline]
timekeeping_update+0x2c5/0x460 kernel/time/timekeeping.c:751
timekeeping_advance+0x7ab/0xac0 kernel/time/timekeeping.c:2198
update_wall_time+0xc/0x20 kernel/time/timekeeping.c:2214
tick_sched_do_timer kernel/time/tick-sched.c:210 [inline]
tick_sched_timer+0xc7/0x560 kernel/time/tick-sched.c:1466
__run_hrtimer kernel/time/hrtimer.c:1690 [inline]
__hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:seqcount_lockdep_reader_access+0x17b/0x1c0 include/linux/seqlock.h:106
Code: f9 4d 85 e4 75 16 e8 b4 8a 61 f9 eb 15 e8 ad 8a 61 f9 e8 e8 ad 92 01 4d 85 e4 74 ea e8 9e 8a 61 f9 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 66 43 c7 44 3e 09 00 00 43 c6 44 3e 0b 00
RSP: 0018:ffffc900030ffa20 EFLAGS: 00000293
RAX: ffffffff88164082 RBX: 0000000000000000 RCX: ffff888023033b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900030ffad0 R08: dffffc0000000000 R09: fffffbfff1ff782c
R10: fffffbfff1ff782c R11: 1ffffffff1ff782b R12: 0000000000000200
R13: ffff8880218b1a18 R14: 1ffff9200061ff44 R15: dffffc0000000000
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:338 [inline]
gc_worker+0x2e2/0x13a0 net/netfilter/nf_conntrack_core.c:1472
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287