INFO: task syz.2.726:6840 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.726 state:D stack:24064 pid: 6840 ppid: 4188 flags:0x00004006
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
perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5127
_free_event+0x34/0xe60 kernel/events/core.c:5133
put_event kernel/events/core.c:5258 [inline]
perf_event_release_kernel+0x832/0x8c0 kernel/events/core.c:5383
perf_release+0x37/0x40 kernel/events/core.c:5393
__fput+0x234/0x930 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
exit_task_work include/linux/task_work.h:33 [inline]
do_exit+0x61e/0x20a0 kernel/exit.c:883
do_group_exit+0x12e/0x300 kernel/exit.c:997
get_signal+0x6ca/0x12c0 kernel/signal.c:2900
arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fefe78c66b0
RSP: 002b:00007fefe5c6c238 EFLAGS: 00000283
RAX: 0000000000000000 RBX: 00007fefe5c6cd30 RCX: 00007fefe7c22120
RDX: 00007fefe5c6c240 RSI: 00007fefe5c6c370 RDI: 000000000000000b
RBP: 000000000000000b R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000000 R12: 0000000000000073
R13: 00007fefe5c6ceb0 R14: 9999999999999999 R15: 0000000000000000
Showing all locks held in the system:
4 locks held by ksoftirqd/1/20:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3948:
#0: ffff88814cbfc098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900025ce2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
4 locks held by kworker/u4:6/4359:
#0: ffff8880169cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000346fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d226b10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:589
#3: ffffffff8c1210b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043
3 locks held by kworker/1:12/7391:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000312fd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8c1210b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043
3 locks held by kworker/1:15/7400:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000353fd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8c1210b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043
3 locks held by kworker/1:51/7445:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90003d1fd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8c1210b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043
3 locks held by kworker/1:54/7448:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90003d4fd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffff888023984240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x271/0x3240 drivers/net/netdevsim/fib.c:1480
2 locks held by syz.0.1593/10054:
#0: ffffffff8d226b10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:499
#1: ffffffff8c1210b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043
4 locks held by syz-executor/10406:
#0: ffff888029f2cff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x5f/0x1030 net/bluetooth/hci_core.c:1737
#1: ffff888029f2c078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x3f4/0x1030 net/bluetooth/hci_core.c:1782
#2: ffffffff8d378768 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline]
#2: ffffffff8d378768 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa4/0x220 net/bluetooth/hci_conn.c:1622
#3: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#3: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845
2 locks held by syz.5.1654/10455:
#0: ffffffff8d226b10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:499
#1: ffffffff8c1210b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043
2 locks held by syz.1.1672/10557:
#0: ffffffff8d226b10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:499
#1: ffffffff8c1210b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043
3 locks held by syz.3.1687/10648:
#0: ffff88801abc0ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x5f/0x1030 net/bluetooth/hci_core.c:1737
#1: ffff88801abc0078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x3f4/0x1030 net/bluetooth/hci_core.c:1782
#2: ffffffff8d378768 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline]
#2: ffffffff8d378768 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa4/0x220 net/bluetooth/hci_conn.c:1622
3 locks held by syz.6.1688/10658:
#0: ffff888041e94ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x5f/0x1030 net/bluetooth/hci_core.c:1737
#1: ffff888041e94078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x3f4/0x1030 net/bluetooth/hci_core.c:1782
#2: ffffffff8d378768 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline]
#2: ffffffff8d378768 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa4/0x220 net/bluetooth/hci_conn.c:1622
=============================================
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 10/25/2025
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: 7448 Comm: kworker/1:54 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events nsim_fib_event_work
RIP: 0010:unwind_next_frame+0x0/0x1d90 arch/x86/kernel/unwind_orc.c:423
Code: 02 31 c0 5b 41 5e 41 5f c3 89 d9 80 e1 07 80 c1 03 38 c1 7c 97 48 89 df e8 0d bc 87 00 eb 8d 66 2e 0f 1f 84 00 00 00 00 00 90 <55> 41 57 41 56 41 55 41 54 53 48 81 ec 88 00 00 00 48 89 fb 49 be
RSP: 0018:ffffc90003d4f060 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc90003d4f120 RCX: 0000000080000001
RDX: dffffc0000000000 RSI: ffffffff814f8606 RDI: ffffc90003d4f068
RBP: ffffc90003d4f0f0 R08: ffffc90003d4f130 R09: 000000000000000c
R10: fffff520007a9e19 R11: 1ffff920007a9e17 R12: ffff88802082bb80
R13: 1ffff920007a9e38 R14: ffffffff81667ac0 R15: ffffc90003d4f068
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555c8dbc3950 CR3: 000000006916f000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
save_stack+0xf3/0x1e0 mm/page_owner.c:119
__reset_page_owner+0x51/0x180 mm/page_owner.c:140
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1340 [inline]
free_pcp_prepare mm/page_alloc.c:1391 [inline]
free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
free_unref_page+0x94/0x280 mm/page_alloc.c:3396
free_slab mm/slub.c:2020 [inline]
discard_slab mm/slub.c:2026 [inline]
__unfreeze_partials+0x1a5/0x200 mm/slub.c:2512
put_cpu_partial+0x12d/0x190 mm/slub.c:2592
qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176
kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283
__kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444
kasan_slab_alloc include/linux/kasan.h:254 [inline]
slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
slab_alloc_node mm/slub.c:3225 [inline]
slab_alloc mm/slub.c:3233 [inline]
kmem_cache_alloc_trace+0x103/0x2a0 mm/slub.c:3250
kmalloc include/linux/slab.h:607 [inline]
kzalloc include/linux/slab.h:738 [inline]
nsim_fib6_rt_create drivers/net/netdevsim/fib.c:545 [inline]
nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:750 [inline]
nsim_fib6_event drivers/net/netdevsim/fib.c:854 [inline]
nsim_fib_event drivers/net/netdevsim/fib.c:887 [inline]
nsim_fib_event_work+0x1109/0x3240 drivers/net/netdevsim/fib.c:1483
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
process_scheduled_works kernel/workqueue.c:2373 [inline]
worker_thread+0xdca/0x12a0 kernel/workqueue.c:2459
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
net_ratelimit: 15996 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:02:00:00:00:00:06, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:02:00:00:00:00:06, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:02:00:00:00:00:06, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:02:00:00:00:00:06, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:a6:b0:8c:33:2c:73, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:02:00:00:00:00:06, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:02:00:00:00:00:06, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:02:00:00:00:00:06, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:02:00:00:00:00:06, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:02:00:00:00:00:06, vlan:0)