INFO: task syz.4.92:4634 blocked for more than 143 seconds. Not tainted 6.1.134-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.92 state:D stack:21256 pid:4634 ppid:4260 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6561 schedule+0xbf/0x180 kernel/sched/core.c:6637 perf_pending_task_sync kernel/events/core.c:5033 [inline] _free_event+0x169/0x1090 kernel/events/core.c:5039 put_event kernel/events/core.c:5164 [inline] perf_event_release_kernel+0x873/0x900 kernel/events/core.c:5289 perf_release+0x37/0x40 kernel/events/core.c:5299 __fput+0x3f6/0x8d0 fs/file_table.c:320 task_work_run+0x246/0x300 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xa6e/0x26a0 kernel/exit.c:871 do_group_exit+0x202/0x2b0 kernel/exit.c:1021 get_signal+0x16cb/0x17a0 kernel/signal.c:2871 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f032618d169 RSP: 002b:00007f0327017fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffff4 RBX: 00007f03263a5fa0 RCX: 00007f032618d169 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000024084200 RBP: 00007f032620e990 R08: 0000200000001a40 R09: 0000200000001a40 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f03263a5fa0 R15: 00007ffd6b10f728 Showing all locks held in the system: 5 locks held by kworker/u4:0/9: #0: ffff8880b8f3a998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #1: ffffffff8d32e7c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #1: ffffffff8d32e7c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #1: ffffffff8d32e7c0 (rcu_read_lock){....}-{1:2}, at: do_perf_sw_event kernel/events/core.c:9683 [inline] #1: ffffffff8d32e7c0 (rcu_read_lock){....}-{1:2}, at: ___perf_sw_event+0x18a/0x6a0 kernel/events/core.c:9721 #2: ffff8880b8f28358 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x62d/0xee0 kernel/time/timer.c:1096 #3: ffffffff9763c080 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x68/0x4e0 lib/debugobjects.c:698 #4: ffffffff976724b8 (&obj_hash[i].lock){-.-.}-{2:2}, at: __debug_check_no_obj_freed lib/debugobjects.c:968 [inline] #4: ffffffff976724b8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_check_no_obj_freed+0xd8/0x4e0 lib/debugobjects.c:1009 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32e990 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32f190 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8d32e7c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32e7c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32e7c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510 2 locks held by kworker/u4:2/33: 1 lock held by dhcpcd/3917: #0: ffffffff8e550ea8 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x29a/0x1ae0 net/ipv4/devinet.c:1081 2 locks held by getty/4008: #0: ffff8880304cd098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x54a/0x1620 drivers/tty/n_tty.c:2198 2 locks held by syz-executor/4238: #0: ffff8880b8f3a998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #1: ffffffff8d32e7c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #1: ffffffff8d32e7c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #1: ffffffff8d32e7c0 (rcu_read_lock){....}-{1:2}, at: do_perf_sw_event kernel/events/core.c:9683 [inline] #1: ffffffff8d32e7c0 (rcu_read_lock){....}-{1:2}, at: ___perf_sw_event+0x18a/0x6a0 kernel/events/core.c:9721 4 locks held by syz.9.899/7759: 1 lock held by syz.2.900/7762: #0: ffffffff8e550ea8 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x59c/0xf70 net/core/dev_ioctl.c:612 2 locks held by syz.0.902/7767: #0: ffffffff8d383d48 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 #1: ffffffff8d333df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #1: ffffffff8d333df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 2 locks held by syz.6.901/7768: #0: ffffffff8e550ea8 (rtnl_mutex){+.+.}-{3:3}, at: ppp_release+0x86/0x1f0 drivers/net/ppp/ppp_generic.c:417 #1: ffffffff8d333df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #1: ffffffff8d333df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.134-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1ca/0x430 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+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 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: 33 Comm: kworker/u4:2 Not tainted 6.1.134-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:__sanitizer_cov_trace_switch+0x2/0xe0 kernel/kcov.c:326 Code: 77 1e 49 ff c2 4c 89 12 48 c7 44 11 08 07 00 00 00 48 89 7c 11 10 48 89 74 11 18 4c 89 44 11 20 c3 0f 1f 80 00 00 00 00 41 57 <41> 56 41 54 53 48 8b 46 08 48 83 c0 f8 48 c1 c0 3d 48 83 f8 07 0f RSP: 0018:ffffc90000a9fb20 EFLAGS: 00000207 RAX: 0000000000000031 RBX: 0000000000000030 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8e552ca0 RDI: 0000000000000030 RBP: 0000000000000030 R08: 0000000000000001 R09: ffffffff88ae3705 R10: 0000000000000003 R11: ffff88801ce61dc0 R12: 0000000000000006 R13: ffffffff8bac46c3 R14: 0000000000000001 R15: ffffffff8bac46c2 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f39ef779ab8 CR3: 000000006740c000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: in_aton+0x255/0x430 net/core/utils.c:61 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:764 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x491/0xab0 drivers/net/netdevsim/dev.c:851 process_one_work+0x917/0x1260 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295