INFO: task syz.2.3961:15517 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.3961 state:D stack:26192 pid:15517 ppid:12497 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x107f/0x4030 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+0x176/0x1050 kernel/events/core.c:5037 put_event kernel/events/core.c:5162 [inline] perf_event_release_kernel+0x7c4/0x850 kernel/events/core.c:5287 perf_release+0x37/0x40 kernel/events/core.c:5297 __fput+0x20a/0x8b0 fs/file_table.c:320 task_work_run+0x1d0/0x260 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0x9d5/0x2570 kernel/exit.c:881 do_group_exit+0x229/0x2e0 kernel/exit.c:1024 get_signal+0x1259/0x1340 kernel/signal.c:2872 arch_do_signal_or_restart+0xc4/0x1310 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: 0033:0x7f8f7619de59 RSP: 002b:00007f8f771260e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000000 RBX: 00007f8f76425fa8 RCX: 00007f8f7619de59 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f8f76425fa8 RBP: 00007f8f76425fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8f76426038 R14: 00007fffc93b1e40 R15: 00007fffc93b1f28 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/27: #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527 2 locks held by getty/4028: #0: ffff88802ff1b098 (&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+0x41e/0x1360 drivers/tty/n_tty.c:2198 3 locks held by kworker/1:4/4273: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #1: ffffc90003fd7d00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #2: ffffffff8dd58c28 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:104 4 locks held by kworker/u4:6/4323: 2 locks held by kworker/0:6/4358: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #1: ffffc90004697d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 1 lock held by syz-executor/13044: #0: ffff8880b8f3ad18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x25/0x130 kernel/sched/core.c:538 2 locks held by syz.3.4627/17698: #0: ffffffff8dd58c28 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8dd58c28 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3495 #1: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962 2 locks held by syz.0.4635/17721: #0: ffffffff8cb82c88 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 #1: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #1: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962 1 lock held by syz.1.4636/17723: #0: ffffffff8cb82c88 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 1 lock held by syz.4.4637/17727: #0: ffffffff8cb82c88 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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+0xf0e/0xf50 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4256 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:in_32bit_syscall arch/x86/include/asm/compat.h:94 [inline] RIP: 0010:in_compat_syscall arch/x86/include/asm/compat.h:100 [inline] RIP: 0010:get_timespec64+0xea/0x1b0 kernel/time/time.c:884 Code: 24 20 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 f8 35 62 00 4c 89 33 65 4c 8b 35 1d 5d 91 7e 49 83 c6 10 4c 89 f0 <48> c1 e8 03 42 0f b6 04 28 84 c0 0f 85 8a 00 00 00 45 8b 36 44 89 RSP: 0018:ffffc90003ee7dc0 EFLAGS: 00000282 RAX: ffff888030c8da10 RBX: ffffc90003ee7ea0 RCX: ffff888030c8da00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003ee7e50 R08: 00000000000f4240 R09: 1ffff920007dcfbd R10: dffffc0000000000 R11: fffff520007dcfbe R12: 1ffff920007dcfb8 R13: dffffc0000000000 R14: ffff888030c8da10 R15: 00000000ffffffff FS: 0000555592223500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2faa3ed2f8 CR3: 000000007a6ef000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __do_sys_clock_nanosleep kernel/time/posix-timers.c:1303 [inline] __se_sys_clock_nanosleep+0x1c3/0x3a0 kernel/time/posix-timers.c:1291 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd033558fd7 Code: 48 89 fa 4c 89 df e8 a8 56 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007fff56ce47c0 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000555592223500 RCX: 00007fd033558fd7 RDX: 00007fff56ce4800 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fff56ce4ce0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004 R13: 00007fff56ce483c R14: 00007fff56ce48d0 R15: 0000000000000000