INFO: task syz.8.9605:9191 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.9605 state:D stack:27472 pid: 9191 ppid: 6129 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5127 _free_event+0x34/0xe60 kernel/events/core.c:5133 put_event kernel/events/core.c:5258 [inline] perf_event_release_kernel+0x83e/0x8d0 kernel/events/core.c:5383 perf_release+0x37/0x40 kernel/events/core.c:5393 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f79e0936799 RSP: 002b:00007ffdef363c48 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f79e0bb1da0 RCX: 00007f79e0936799 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f79e0bb1da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007f79e0bb1cb0 R11: 0000000000000246 R12: 00000000001debb4 R13: 00007f79e0bb018c R14: 00000000001de975 R15: 00007f79e0bb0180 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by dhcpcd/3852: 2 locks held by getty/3951: #0: ffff88814c8a7098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158 4 locks held by kworker/u4:24/25712: 2 locks held by kworker/0:1/5233: #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc9000330fd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 2 locks held by kworker/0:4/5936: #0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc900032dfd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 4 locks held by kworker/u4:12/9650: 2 locks held by syz.5.10433/11834: #0: ffffffff8c36c168 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 #1: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845 2 locks held by syz.2.10444/11868: #0: ffff888072d98e10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #0: ffff888072d98e10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:650 [inline] #0: ffff888072d98e10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1345 #1: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #1: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845 ============================================= 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 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11834 Comm: syz.5.10433 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:__lock_release kernel/locking/lockdep.c:5329 [inline] RIP: 0010:lock_release+0x2a8/0x8a0 kernel/locking/lockdep.c:5643 Code: f0 ff 42 0f b6 04 2b 84 c0 0f 85 bc 04 00 00 41 89 3e 45 85 ff 4c 8b 7c 24 20 0f 85 9f 02 00 00 48 8b 44 24 40 42 0f b6 04 28 <84> c0 0f 85 73 04 00 00 48 8b 04 24 89 10 4c 89 e0 48 c1 e8 03 42 RSP: 0018:ffffc90002eaf1c0 EFLAGS: 00000087 RAX: 0000000000000000 RBX: 1ffff110091538f0 RCX: 0000000000000001 RDX: 0000000000000006 RSI: ffffe8ffffc78748 RDI: ffff888048a9c760 RBP: ffffc90002eaf2d8 R08: ffffffff8d89e36f R09: 1ffffffff1b13c6d R10: dffffc0000000000 R11: fffffbfff1b13c6e R12: ffff888048a9c760 R13: dffffc0000000000 R14: ffff888048a9c780 R15: 0000000000000046 FS: 0000555566bb6500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1dd7367158 CR3: 000000007defc000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff1 DR7: 0000000000000600 Call Trace: do_write_seqcount_end include/linux/seqlock.h:565 [inline] psi_group_change+0xadb/0x1150 kernel/sched/psi.c:752 psi_task_switch+0x499/0x7d0 kernel/sched/psi.c:882 psi_sched_switch kernel/sched/stats.h:148 [inline] __schedule+0x1d02/0x43c0 kernel/sched/core.c:6390 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6571 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6596 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 on_each_cpu_cond_mask+0x71/0x80 kernel/smp.c:1135 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1442 [inline] text_poke_bp_batch+0x77e/0x830 arch/x86/kernel/alternative.c:-1 text_poke_bp+0xd9/0x160 arch/x86/kernel/alternative.c:1879 __static_call_transform+0x2f2/0x510 arch/x86/kernel/static_call.c:111 arch_static_call_transform+0xa0/0x250 arch/x86/kernel/static_call.c:157 __static_call_update+0xeb/0x5c0 kernel/static_call_inline.c:136 tracepoint_update_call kernel/tracepoint.c:317 [inline] tracepoint_remove_func kernel/tracepoint.c:419 [inline] tracepoint_probe_unregister+0x72f/0x930 kernel/tracepoint.c:551 trace_event_reg+0x218/0x260 kernel/trace/trace_events.c:-1 perf_trace_event_unreg+0xb3/0x1b0 kernel/trace/trace_event_perf.c:162 perf_trace_destroy+0x9a/0x140 kernel/trace/trace_event_perf.c:241 _free_event+0x850/0xe60 kernel/events/core.c:5164 put_event kernel/events/core.c:5258 [inline] perf_event_release_kernel+0x83e/0x8d0 kernel/events/core.c:5383 perf_release+0x37/0x40 kernel/events/core.c:5393 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f3ffa659799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd2ee12718 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f3ffa8d4da0 RCX: 00007f3ffa659799 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f3ffa8d4da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007f3ffa8d4cb0 R11: 0000000000000246 R12: 000000000020572e R13: 00007f3ffa8d309c R14: 0000000000205867 R15: 00007f3ffa8d3090