INFO: task syz.0.219:6496 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.219 state:D stack:23472 pid:6496 ppid:5788 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+0xf6/0x180 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: 0033:0x7f817bb8efc9
RSP: 002b:00007f817ca27fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007f817bde5fa0 RCX: 00007f817bb8efc9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000630c1000
RBP: 00007f817bc11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f817bde6038 R14: 00007f817bde5fa0 R15: 00007ffc1dec16e8
Showing all locks held in the system:
3 locks held by kworker/u4:0/11:
#0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffffffff8dfbb688 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286
2 locks held by kworker/1:1/28:
#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: ffffc90000a4fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90000a4fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
1 lock held by khungtaskd/29:
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
2 locks held by getty/5555:
#0: ffff888030c780a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
2 locks held by syz.5.845/8764:
#0: ffffffff8dfbb688 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8dfbb688 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3511
#1: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
#1: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x448/0x830 kernel/rcu/tree_exp.h:1004
1 lock held by syz.6.849/8780:
#0: ffffffff8dfbb688 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x3b9/0x1fd0 drivers/net/tun.c:3121
1 lock held by syz.6.849/8783:
#0: ffffffff8dfbb688 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x7d2/0x1170 net/core/dev_ioctl.c:785
1 lock held by syz.2.850/8782:
#0: ffffffff8dfbb688 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x86a/0x1170 net/core/dev_ioctl.c:810
1 lock held by syz.2.850/8786:
#0: ffffffff8dfbb688 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x86a/0x1170 net/core/dev_ioctl.c:810
1 lock held by syz.4.851/8788:
#0: ffffffff8dfbb688 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x3b9/0x1fd0 drivers/net/tun.c:3121
1 lock held by syz.4.851/8789:
#0: ffffffff8dfbb688 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x7d2/0x1170 net/core/dev_ioctl.c:785
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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: 37 Comm: kworker/u4:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:lock_release+0x566/0x8b0 kernel/locking/lockdep.c:5777
Code: ff 65 0f c1 05 03 0f 9b 7e 83 f8 01 75 75 48 c7 84 24 80 00 00 00 00 00 00 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 <75> 75 f7 44 24 50 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45
RSP: 0018:ffffc90000adf7e0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 95e32fa3747e6c62 RCX: b2a41b9068c82e00
RDX: 0000000000000004 RSI: ffffffff8aaace60 RDI: ffffffff8afc64c0
RBP: ffffc90000adf8f0 R08: ffffffff8e4a856f R09: 1ffffffff1c950ad
R10: dffffc0000000000 R11: fffffbfff1c950ae R12: ffff888018298b80
R13: dffffc0000000000 R14: ffff888018298ad0 R15: 1ffff9200015bf08
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c385373 CR3: 000000002c9e4000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff1 DR7: 0000000000000600
Call Trace:
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
_raw_spin_unlock_irqrestore+0x71/0x110 kernel/locking/spinlock.c:194
__debug_check_no_obj_freed lib/debugobjects.c:999 [inline]
debug_check_no_obj_freed+0x51f/0x540 lib/debugobjects.c:1020
slab_free_hook mm/slub.c:1786 [inline]
slab_free_freelist_hook+0xd2/0x1b0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
kmem_cache_free+0xf8/0x280 mm/slub.c:3852
nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
nsim_dev_trap_report_work+0x76f/0xb00 drivers/net/netdevsim/dev.c:851
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