INFO: task syz.5.7466:2046 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.7466 state:D stack:23568 pid:2046 ppid:1472 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 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+0x83e/0x8d0 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+0x1d0/0x260 kernel/task_work.c:203 get_signal+0x11a6/0x1350 kernel/signal.c:2648 arch_do_signal_or_restart+0xc4/0x1350 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:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f454899cdd9 RSP: 002b:00007f4549782fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffffc RBX: 00007f4548c15fa0 RCX: 00007f454899cdd9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040100000 RBP: 00007f4548a32d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f4548c16038 R14: 00007f4548c15fa0 R15: 00007fff8397ded8 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2df70 (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: ffffffff8cb2e790 (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: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4030: #0: ffff88802fe44098 (&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+0x429/0x1390 drivers/tty/n_tty.c:2198 2 locks held by kworker/0:3/27302: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc900039d7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 2 locks held by syz.0.8213/5422: #0: ffffffff8cb826a8 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 #1: ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962 2 locks held by syz.9.8216/5417: #0: ffff88801788e210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #0: ffff88801788e210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline] #0: ffff88801788e210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1399 #1: ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #1: ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962 1 lock held by syz.2.8215/5418: #0: ffffffff8cb826a8 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 1 lock held by syz.2.8215/5420: 1 lock held by syz.1.8217/5430: #0: ffffffff8dd4a488 (bpf_dispatcher_xdp.mutex){+.+.}-{3:3}, at: bpf_dispatcher_change_prog+0xc8/0xf10 kernel/bpf/dispatcher.c:146 1 lock held by dhcpcd/5426: #0: ffff888027170130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline] #0: ffff888027170130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249 1 lock held by syz.8.8219/5434: #0: ffffffff8dd4a488 (bpf_dispatcher_xdp.mutex){+.+.}-{3:3}, at: bpf_dispatcher_change_prog+0xc8/0xf10 kernel/bpf/dispatcher.c:146 ============================================= 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 04/18/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3e6/0x460 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: 17546 Comm: kworker/u4:40 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:hlock_class kernel/locking/lockdep.c:223 [inline] RIP: 0010:__lock_acquire+0x1091/0x7d10 kernel/locking/lockdep.c:5045 Code: 4c 8b bc 24 c0 00 00 00 0f 85 02 03 00 00 48 83 7c 24 60 00 0f 84 39 02 00 00 48 8b 44 24 78 48 8d 58 f8 48 89 d8 48 c1 e8 03 <42> 0f b6 04 00 84 c0 0f 85 16 5e 00 00 8b 03 89 c3 81 e3 ff 1f 00 RSP: 0018:ffffc9000d3bf4a0 EFLAGS: 00000802 RAX: 1ffff1100d092c97 RBX: ffff8880684964b8 RCX: 00000000e1531c22 RDX: 0000000076f58567 RSI: 000000003652f4f7 RDI: ffffffff90af9248 RBP: ffffc9000d3bf6f0 R08: dffffc0000000000 R09: 1ffffffff215f249 R10: dffffc0000000000 R11: fffffbfff215f24a R12: 0000000090ca6486 R13: 000000000a5a46df R14: 00000000d0052189 R15: ffff888068496410 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fadcffec4b8 CR3: 000000007d424000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] crng_make_state+0x1ee/0xb00 drivers/char/random.c:328 _get_random_bytes+0xfc/0x250 drivers/char/random.c:366 eth_random_addr include/linux/etherdevice.h:232 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:755 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x334/0xaf0 drivers/net/netdevsim/dev.c:851 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295