INFO: task udevd:28105 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:22392 pid:28105 tgid:28105 ppid:5192 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7183
__schedule_loop kernel/sched/core.c:7262 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7277
io_schedule+0x7f/0xd0 kernel/sched/core.c:8104
folio_wait_bit_common+0x6d8/0xbc0 mm/filemap.c:1323
folio_put_wait_locked mm/filemap.c:1492 [inline]
do_read_cache_folio+0x1ad/0x590 mm/filemap.c:4088
read_mapping_folio include/linux/pagemap.h:1017 [inline]
read_part_sector+0xb6/0x2b0 block/partitions/core.c:724
adfspart_check_POWERTEC+0x9a/0x7a0 block/partitions/acorn.c:450
check_partition block/partitions/core.c:143 [inline]
blk_add_partitions block/partitions/core.c:591 [inline]
bdev_disk_changed+0x817/0x1770 block/partitions/core.c:695
blkdev_get_whole+0x380/0x510 block/bdev.c:756
bdev_open+0x31e/0xd30 block/bdev.c:965
blkdev_open+0x470/0x610 block/fops.c:697
do_dentry_open+0x785/0x14e0 fs/open.c:947
vfs_open+0x3b/0x340 fs/open.c:1079
do_open fs/namei.c:4699 [inline]
path_openat+0x2e08/0x3860 fs/namei.c:4858
do_file_open+0x23e/0x4a0 fs/namei.c:4887
do_sys_openat2+0x113/0x200 fs/open.c:1364
do_sys_open fs/open.c:1370 [inline]
__do_sys_openat fs/open.c:1386 [inline]
__se_sys_openat fs/open.c:1381 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1381
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd6f55de407
RSP: 002b:00007ffe13945160 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fd6f5552880 RCX: 00007fd6f55de407
RDX: 00000000000a0800 RSI: 000055a34e8c6360 RDI: ffffffffffffff9c
RBP: 000055a34e8b5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055a34e8ca830
R13: 000055a34e8c3190 R14: 0000000000000000 R15: 000055a34e8ca830
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e95d020 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e95d020 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e95d020 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5577:
#0: ffff888035c620a0 (&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+0x45c/0x13a0 drivers/tty/n_tty.c:2211
1 lock held by udevd/28105:
#0: ffff888027934350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:953
1 lock held by syz-executor/29236:
4 locks held by syz-executor/29255:
#0: ffff88809ffe8ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff88809ffe8ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff88809ffe80b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5356
#2: ffffffff8ff5c720 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#2: ffffffff8ff5c720 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2650
#3: ffff88807dd4a2f8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x92/0x570 net/bluetooth/l2cap_core.c:1777
1 lock held by syz-executor/29719:
#0: ffffffff8e963328 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#0: ffffffff8e963328 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
1 lock held by syz-executor/30632:
3 locks held by kworker/1:3/31884:
#0: ffff88813fe53140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline]
#0: ffff88813fe53140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3371
#1: ffffc9000d48fc40 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline]
#1: ffffc9000d48fc40 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3371
#2: ffffffff8e963328 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#2: ffffffff8e963328 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
=============================================
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 04/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [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:346 [inline]
watchdog+0xfaa/0x1000 kernel/hung_task.c:515
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: 13118 Comm: kworker/u8:12 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:37 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline]
RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline]
RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:208
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 cc cc cc cc cc 89 f6 31 d2 e9 96 f2 77 03 66 0f 1f 44 00
RSP: 0018:ffffc9001a16f3d0 EFLAGS: 00000046
RAX: 0000000000016eb6 RBX: ffff8880b8623e40 RCX: 0000000000000838
RDX: 0000000000000000 RSI: 0000000000016eb6 RDI: 0000000000000838
RBP: ffffc9001a16f490 R08: ffffffff81b2a065 R09: ffffffff9a4d75c8
R10: 0000000000000003 R11: ffffffff8173ba10 R12: 0000000000016eb6
R13: dffffc0000000000 R14: 00000000100053e2 R15: 0000000000000020
FS: 0000000000000000(0000) GS:ffff888125243000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f03ce347e20 CR3: 000000000e74a000 CR4: 00000000003526f0
Call Trace:
apic_write arch/x86/include/asm/apic.h:405 [inline]
lapic_next_event+0x11/0x20 arch/x86/kernel/apic/apic.c:417
clockevents_program_event+0x385/0x5f0 kernel/time/clockevents.c:369
hrtimer_start_range_ns+0x940/0xed0 kernel/time/hrtimer.c:1492
hrtimer_start include/linux/hrtimer.h:220 [inline]
hrtick_cond_restart kernel/sched/core.c:919 [inline]
hrtick_schedule_exit kernel/sched/core.c:981 [inline]
finish_lock_switch kernel/sched/core.c:5118 [inline]
finish_task_switch+0x3cd/0xbe0 kernel/sched/core.c:5237
context_switch kernel/sched/core.c:5385 [inline]
__schedule+0x17bc/0x5680 kernel/sched/core.c:7183
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7364
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
on_each_cpu_cond_mask+0x7a/0x80 kernel/smp.c:1058
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2761 [inline]
smp_text_poke_batch_finish+0xec2/0x1160 arch/x86/kernel/alternative.c:3054
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:240
static_key_disable+0x1a/0x20 kernel/jump_label.c:248
toggle_allocation_gate+0x1fe/0x290 mm/kfence/core.c:907
process_one_work kernel/workqueue.c:3288 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3371
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3452
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