INFO: task syz.0.903:7845 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.903 state:D stack:22400 pid:7845 ppid:4267 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
perf_pending_task_sync kernel/events/core.c:5031 [inline]
_free_event+0x171/0x10a0 kernel/events/core.c:5037
put_event kernel/events/core.c:5162 [inline]
perf_event_release_kernel+0x832/0x8c0 kernel/events/core.c:5287
perf_release+0x37/0x40 kernel/events/core.c:5297
__fput+0x22c/0x920 fs/file_table.c:320
task_work_run+0x1ca/0x250 kernel/task_work.c:203
get_signal+0x11a6/0x1350 kernel/signal.c:2648
arch_do_signal_or_restart+0xb7/0x1240 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1abc78efc9
RSP: 002b:00007f1abd61bfe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007f1abc9e6090 RCX: 00007f1abc78efc9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000042000000
RBP: 00007f1abc811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f1abc9e6128 R14: 00007f1abc9e6090 R15: 00007fff05c8c218
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2b630 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2be50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/27:
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by getty/4029:
#0: ffff88803001c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198
2 locks held by kworker/0:7/4379:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004bdfd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
3 locks held by kworker/0:8/4381:
#0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#1: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#1: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: do_perf_sw_event kernel/events/core.c:9706 [inline]
#1: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: ___perf_sw_event+0x13c/0x630 kernel/events/core.c:9744
#2: ffff88806228b240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x26b/0x32b0 drivers/net/netdevsim/fib.c:1491
2 locks held by syz.9.1651/11192:
#0: ffffffff8cb7fd28 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
#1: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#1: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x346/0x830 kernel/rcu/tree_exp.h:962
1 lock held by syz.3.1652/11200:
#0: ffffffff8cb7fd28 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
2 locks held by syz.6.1660/11241:
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: srcu_read_lock include/linux/srcu.h:165 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: perf_init_event kernel/events/core.c:11624 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: perf_event_alloc+0xbe2/0x21b0 kernel/events/core.c:11950
#1: ffffffff8cb7fd28 (event_mutex){+.+.}-{3:3}, at: perf_trace_init+0x4c/0x2d0 kernel/trace/trace_event_perf.c:221
1 lock held by syz.6.1660/11242:
#0: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#0: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962
2 locks held by syz.7.1661/11245:
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: srcu_read_lock include/linux/srcu.h:165 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: perf_init_event kernel/events/core.c:11624 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: perf_event_alloc+0xbe2/0x21b0 kernel/events/core.c:11950
#1: ffffffff8cb7fd28 (event_mutex){+.+.}-{3:3}, at: perf_trace_init+0x4c/0x2d0 kernel/trace/trace_event_perf.c:221
=============================================
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 10/02/2025
Call Trace:
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xeee/0xf30 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4915 Comm: kworker/u4:14 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events_unbound bpf_map_free_deferred
RIP: 0010:remove_class_from_lock_chain kernel/locking/lockdep.c:5952 [inline]
RIP: 0010:remove_class_from_lock_chains kernel/locking/lockdep.c:5991 [inline]
RIP: 0010:zap_class+0x160/0x830 kernel/locking/lockdep.c:6036
Code: 3f 4d 85 ff 0f 94 c0 49 83 c7 f8 0f 94 c1 08 c1 75 b5 4d 89 fd 49 c1 ed 03 43 0f b6 44 35 00 84 c0 0f 85 45 02 00 00 45 8b 27 <41> f6 c4 fc 0f 84 03 02 00 00 41 c1 ec 08 44 89 e5 01 ed 49 81 fc
RSP: 0018:ffffc9000c53fa48 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000bc9 RCX: 000000000002fe00
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffff8fa89dca
RBP: 000000000005fccc R08: dffffc0000000000 R09: fffffbfff215277d
R10: fffffbfff215277d R11: 1ffffffff215277c R12: 0000000000b23715
R13: 1ffffffff2168b30 R14: dffffc0000000000 R15: ffffffff90b45980
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f598c4c0700 CR3: 000000007c7df000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
__lockdep_free_key_range kernel/locking/lockdep.c:6162 [inline]
lockdep_unregister_key+0x38f/0x530 kernel/locking/lockdep.c:6364
htab_map_free+0x8d1/0x9b0 kernel/bpf/hashtab.c:1543
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295