INFO: task udevd:7604 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:26824 pid:7604 tgid:7604 ppid:4978 task_flags:0x400040 flags:0x00080802 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d4/0x5630 kernel/sched/core.c:7239 __schedule_loop kernel/sched/core.c:7316 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7331 io_schedule+0x7f/0xd0 kernel/sched/core.c:8159 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:4128 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:794 bdev_open+0x324/0xd70 block/bdev.c:1003 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: 0033:0x7f8c32aa7407 RSP: 002b:00007ffd1314df00 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f8c331a4880 RCX: 00007f8c32aa7407 RDX: 00000000000a0800 RSI: 000055eafad8c430 RDI: ffffffffffffff9c RBP: 000055eafad73910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000055eafad9a6d0 R13: 000055eafad81190 R14: 00007ffd1314dfc8 R15: 000055eafad9a6d0 Showing all locks held in the system: locks held by ksoftirqd/0/15: 1, last CPU#0: #0: ffff8880b863b4e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667 locks held by khungtaskd/30: 1, last CPU#1: #0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6793 locks held by syslogd/4960: 1, last CPU#0: #0: ffff8880b863b4e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667 locks held by getty/5366: 2, on CPU#1: #0: ffff888036a330a0 (&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 locks held by kworker/0:4/5733: 2, last CPU#0: #0: ffff88807fcb9140 ((wq_completion)wg-crypt-wg0#8){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88807fcb9140 ((wq_completion)wg-crypt-wg0#8){+.+.}-{0:0}, at: process_scheduled_works+0xa1a/0x14c0 kernel/workqueue.c:3405 #1: ffff8880b8624408 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933 locks held by kworker/u8:1/5489: 5, last CPU#0: #0: ffff888032c16940 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff888032c16940 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0xa1a/0x14c0 kernel/workqueue.c:3405 #1: ffffc9000337fc40 ((work_completion)(&(&bat_priv->tt.work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000337fc40 ((work_completion)(&(&bat_priv->tt.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa1a/0x14c0 kernel/workqueue.c:3405 #2: ffffc90000007d00 ((&q->adapt_timer)#3){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x5f0 kernel/time/timer.c:1745 #3: ffffffff9a7d3748 (&____s->seqcount#2){----}-{0:0}, at: ktime_get+0x45/0x220 kernel/time/timekeeping.c:1002 #4: ffffffff9aa2bcb0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xb7/0x420 lib/debugobjects.c:873 locks held by kworker/u8:39/5530: 6, on CPU#1: #0: ffff88801c296140 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88801c296140 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa1a/0x14c0 kernel/workqueue.c:3405 #1: ffffc9000438fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000438fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa1a/0x14c0 kernel/workqueue.c:3405 #2: ffffffff90027b28 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:677 #3: ffff88808c98c128 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline] #3: ffff88808c98c128 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:124 [inline] #3: ffff88808c98c128 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x420 net/devlink/core.c:575 #4: ffff88808c98b258 (&devlink->lock_key#19){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:308 [inline] #4: ffff88808c98b258 (&devlink->lock_key#19){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:125 [inline] #4: ffff88808c98b258 (&devlink->lock_key#19){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x142/0x420 net/devlink/core.c:575 #5: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #5: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 locks held by udevd/7604: 1, on CPU#1: #0: ffff8880276aa350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:991 locks held by syz-executor/10233: 1, on CPU#1: #0: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #0: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 locks held by dhcpcd/10363: 1, on CPU#1: #0: ffff888052316260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] #0: ffff888052316260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe90 net/packet/af_packet.c:3229 locks held by sed/10369: 1, last CPU#0: #0: ffff88808529c378 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline] #0: ffff88808529c378 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1dd/0x4e0 mm/util.c:579 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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: 16246 Comm: kworker/0:12 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: events_power_efficient neigh_managed_work RIP: 0010:lapic_next_event+0x0/0x20 arch/x86/kernel/apic/apic.c:417 Code: 57 7c 07 c6 05 10 5f fe 11 01 0f b6 05 e9 5c fe 11 c3 cc cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 89 fe bf 80 03 00 00 e8 2f 27 01 00 31 c0 c3 cc cc RSP: 0018:ffffc90000007e58 EFLAGS: 00000046 RAX: 1ffff110170c47a3 RBX: ffff8880b8623c80 RCX: dffffc0000000000 RDX: 8000000000000100 RSI: ffff8880b8623c80 RDI: 000000000000000f RBP: ffffc90000007f08 R08: 0000000000000100 R09: 0000000000080000 R10: 0000000000000000 R11: ffffffff8174c510 R12: ffffffff8174c510 R13: 1ffff110170c4799 R14: 0000000000000000 R15: ffff8880b8623ccc FS: 0000000000000000(0000) GS:ffff888124f24000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005639653954a0 CR3: 000000007f9de000 CR4: 00000000003526f0 Call Trace: clockevents_program_event+0x44e/0x630 kernel/time/clockevents.c:381 hrtimer_update_softirq_timer kernel/time/hrtimer.c:1336 [inline] hrtimer_run_softirq+0x255/0x2e0 kernel/time/hrtimer.c:2144 handle_softirqs+0x226/0x860 kernel/softirq.c:645 do_softirq+0x77/0xd0 kernel/softirq.c:546 __local_bh_enable_ip+0x100/0x140 kernel/softirq.c:473 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa88/0x14c0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 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 net_ratelimit: 1 callbacks suppressed IPVS: sed: UDP 224.0.0.2:0 - no destination available IPVS: sed: UDP 224.0.0.2:0 - no destination available IPVS: sed: UDP 224.0.0.2:0 - no destination available