INFO: task syz.1.4322:20555 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.4322 state:D stack:23984 pid:20555 ppid: 15604 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 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+0x83e/0x8d0 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+0x626/0x20c0 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+0xe7/0x12c0 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: 0033:0x7f9de024f819
RSP: 002b:00007f9dde4a8fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007f9de04c8fa0 RCX: 00007f9de024f819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000126400
RBP: 00007f9de02e5c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f9de04c9038 R14: 00007f9de04c8fa0 R15: 00007ffdf7948188
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c31eb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/u4:3/1339:
#0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc90005767d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
4 locks held by kworker/u4:5/3084:
#0: ffff888016dcd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000d7ffd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffffffff8d431510 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:589
#3: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: cangw_pernet_exit+0xe/0x20 net/can/gw.c:1279
2 locks held by getty/3948:
#0: ffff88802c647098 (&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+0x5df/0x1a70 drivers/tty/n_tty.c:2158
3 locks held by kworker/0:20/6322:
#0: ffff88814c6c4938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000337fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xca/0x1540 net/ipv6/addrconf.c:4110
2 locks held by kworker/u4:8/7111:
#0: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
#1: ffffffff8c31eb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
3 locks held by kworker/1:37/20321:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000354fd00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#2: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
2 locks held by kworker/1:43/20327:
#0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000385fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
3 locks held by syz-executor/21902:
#0: ffff88805d794ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x5f/0x1030 net/bluetooth/hci_core.c:1737
#1: ffff88805d794078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x3f4/0x1030 net/bluetooth/hci_core.c:1782
#2: ffffffff8d583928 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline]
#2: ffffffff8d583928 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa4/0x220 net/bluetooth/hci_conn.c:1622
3 locks held by syz.6.5560/25163:
#0: ffff8880785e8ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x5f/0x1030 net/bluetooth/hci_core.c:1737
#1: ffff8880785e8078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x3f4/0x1030 net/bluetooth/hci_core.c:1782
#2: ffffffff8d583928 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1517 [inline]
#2: ffffffff8d583928 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa4/0x220 net/bluetooth/hci_conn.c:1622
1 lock held by syz.6.5560/25164:
2 locks held by syz.7.5633/25430:
#0: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:699 [inline]
#0: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3440
#1: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7111 Comm: kworker/u4:8 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: bat_events batadv_nc_worker
RIP: 0010:check_preemption_disabled+0x37/0x110 lib/smp_processor_id.c:55
Code: 04 25 28 00 00 00 48 89 44 24 08 65 8b 05 79 2b 45 76 65 8b 0d e2 85 45 76 f7 c1 ff ff ff 7f 74 1f 65 48 8b 0c 25 28 00 00 00 <48> 3b 4c 24 08 0f 85 c4 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d c3
RSP: 0018:ffffc9000339f8c8 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffffff8c1edd18 RCX: 1f2e586856a07d00
RDX: ffffffff8991c816 RSI: ffffffff8a79fe20 RDI: ffffffff8a79fde0
RBP: ffffc9000339f9f0 R08: ffffffff8d89f06f R09: 1ffffffff1b13e0d
R10: dffffc0000000000 R11: fffffbfff1b13e0e R12: dffffc0000000000
R13: 1ffff92000673f28 R14: 0000607f46c35e28 R15: ffffffff8c1edca0
FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056549dad9f70 CR3: 000000007db4f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
perf_trace_lock+0xe4/0x390 include/trace/events/lock.h:39
trace_lock_release include/trace/events/lock.h:58 [inline]
lock_release+0x84a/0x8a0 kernel/locking/lockdep.c:5634
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:174 [inline]
_raw_spin_unlock_bh+0x17/0x30 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:409 [inline]
batadv_nc_purge_paths+0x316/0x3b0 net/batman-adv/network-coding.c:475
batadv_nc_worker+0x2e7/0x5c0 net/batman-adv/network-coding.c:724
process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287