INFO: task syz.1.3509:14952 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.3509      state:D stack:22632 pid:14952 ppid:12111  flags:0x00004006
Call Trace:
 <TASK>
 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+0x9c/0x7b0 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: 0033:0x7f6d9178f6c9
RSP: 002b:00007f6d92583fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007f6d919e5fa0 RCX: 00007f6d9178f6c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000042164000
RBP: 00007f6d91811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f6d919e6038 R14: 00007f6d919e5fa0 R15: 00007ffc96375dc8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 #0: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
 #0: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
1 lock held by syslogd/5140:
 #0: ffff8880b8f3c218 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558
4 locks held by udevd/5158:
2 locks held by getty/5554:
 #0: ffff888030d920a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000328b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
2 locks held by kworker/1:10/6094:
 #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: ffffc900033a7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
 #1: ffffc900033a7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
4 locks held by kworker/u4:18/15380:
 #0: ffff888017873938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
 #0: ffff888017873938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #1: ffffc9000ff27d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
 #1: ffffc9000ff27d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
 #2: ffffffff8dfaeed0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x136/0xb90 net/core/net_namespace.c:606
 #3: ffffffff8dfbbd08 (rtnl_mutex){+.+.}-{3:3}, at: wg_netns_pre_exit+0x1c/0x1d0 drivers/net/wireguard/device.c:422
5 locks held by kworker/u4:30/18101:
2 locks held by syz.5.4773/18186:
 #0: ffffffff8dfbbd08 (rtnl_mutex){+.+.}-{3:3}, at: ppp_release+0x8a/0x1f0 drivers/net/ppp/ppp_generic.c:418
 #1: ffffffff8cd358b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
 #1: ffffffff8cd358b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x448/0x830 kernel/rcu/tree_exp.h:1004
1 lock held by syz.7.4781/18209:
 #0: ffffffff8dfbbd08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
 #0: ffffffff8dfbbd08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6469
1 lock held by syz.7.4781/18210:
 #0: ffffffff8dfbbd08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
 #0: ffffffff8dfbbd08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6469

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 18085 Comm: kworker/u4:19 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:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:212
Code: 00 0f 0b 0f 1f 80 00 00 00 00 f3 0f 1e fa 53 48 89 fb e8 13 00 00 00 48 8b 3d 0c 00 c5 0c 48 89 de 5b e9 a3 8a 56 00 cc cc cc <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0d 20 28 7e 7e 65 8b 15 21 28 7e
RSP: 0018:ffffc900118e7468 EFLAGS: 00000282
RAX: ffffffff813ac057 RBX: 0000000080000001 RCX: 0000000000000000
RDX: ffff888050e90000 RSI: 0000000080000001 RDI: 0000000000000000
RBP: ffffc900118e75a8 R08: ffff888050e90000 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000000 R12: ffffc900118e75a8
R13: dffffc0000000000 R14: ffffc900118e7640 R15: ffffc900118e75b8
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdf707b4198 CR3: 000000000cb30000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 unwind_next_frame+0x1d24/0x2970 arch/x86/kernel/unwind_orc.c:672
 __unwind_start+0x66a/0x7e0 arch/x86/kernel/unwind_orc.c:760
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xf8/0x190 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1811 [inline]
 slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837
 slab_free mm/slub.c:3830 [inline]
 __kmem_cache_free+0xba/0x1f0 mm/slub.c:3843
 skb_kfree_head net/core/skbuff.c:945 [inline]
 skb_free_head net/core/skbuff.c:957 [inline]
 skb_release_data+0x634/0x800 net/core/skbuff.c:987
 skb_release_all net/core/skbuff.c:1053 [inline]
 __kfree_skb net/core/skbuff.c:1067 [inline]
 consume_skb+0xb2/0x110 net/core/skbuff.c:1283
 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
 </TASK>