INFO: task syz.0.41:6037 blocked for more than 143 seconds.
Not tainted 6.6.102-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.41 state:D stack:22256 pid:6037 ppid:5840 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
perf_pending_task_sync kernel/events/core.c:5242 [inline]
_free_event+0x174/0xf30 kernel/events/core.c:5248
put_event kernel/events/core.c:5376 [inline]
perf_event_release_kernel+0x836/0x8c0 kernel/events/core.c:5501
perf_release+0x3b/0x40 kernel/events/core.c:5511
__fput+0x234/0x970 fs/file_table.c:384
task_work_run+0x1ce/0x250 kernel/task_work.c:239
get_signal+0x1235/0x1400 kernel/signal.c:2678
arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f213eb8ebe9
RSP: 002b:00007f213fa44fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007f213edb5fa0 RCX: 00007f213eb8ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000630c1000
RBP: 00007f213ec11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f213edb6038 R14: 00007f213edb5fa0 R15: 00007ffc208d35a8
Showing all locks held in the system:
1 lock held by khungtaskd/29:
#0: ffffffff8cd2fbe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2fbe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2fbe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
2 locks held by getty/5548:
#0: ffff8880323ba0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
2 locks held by kworker/1:1/5827:
#0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc900049dfd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc900049dfd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
2 locks held by syz.8.599/7720:
#0: ffffffff8dfbba48 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8dfbba48 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3511
#1: ffffffff8cd35bb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
#1: ffffffff8cd35bb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x448/0x830 kernel/rcu/tree_exp.h:1004
2 locks held by syz.9.600/7726:
#0: ffff888020e90688 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0xf4/0x810 net/netlink/af_netlink.c:2346
#1: ffffffff8dfbba48 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0x71f/0xde0 net/netlink/af_netlink.c:2273
1 lock held by syz.5.602/7730:
#0: ffffffff8dfbba48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
#0: ffffffff8dfbba48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6472
1 lock held by syz.1.603/7735:
#0: ffffffff8dfbba48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
#0: ffffffff8dfbba48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6472
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.6.102-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf41/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 61 Comm: kworker/u4:4 Not tainted 6.6.102-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4773 [inline]
RIP: 0010:__lock_acquire+0x5d0/0x7c80 kernel/locking/lockdep.c:5087
Code: 7c 24 10 0f 85 63 64 00 00 83 3d ca 9a 83 15 00 0f 84 f6 01 00 00 31 db 48 81 c3 c8 00 00 00 48 89 d8 48 c1 e8 03 0f b6 04 10 <84> c0 0f 85 1b 63 00 00 44 0f b6 33 48 8b 44 24 48 0f b6 04 10 84
RSP: 0018:ffffc900015a7640 EFLAGS: 00000806
RAX: 0000000000000000 RBX: ffffffff90714e18 RCX: ffffffff81670940
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff90da3510
RBP: ffffc900015a7888 R08: ffffffff90da3517 R09: 1ffffffff21b46a2
R10: dffffc0000000000 R11: fffffbfff21b46a3 R12: ffff8880186fe4c4
R13: ffff8880186fda00 R14: 0000000000000000 R15: ffff8880186fe550
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000ffd000 CR3: 000000000cb30000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa8/0xf0 kernel/locking/spinlock.c:162
prepare_to_wait_event+0x20/0x470 kernel/sched/wait.c:315
toggle_allocation_gate+0x12a/0x250 mm/kfence/core.c:833
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293