INFO: task syz.6.505:6451 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.6.505 state:D stack:23736 pid:6451 ppid:4499 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 get_signal+0x15d0/0x17a0 kernel/signal.c:2648 arch_do_signal_or_restart+0xb3/0x12a0 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+0x47/0x80 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f7cac58e169 RSP: 002b:00007f7cad351fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: fffffffffffffffc RBX: 00007f7cac7b5fa0 RCX: 00007f7cac58e169 RDX: 00002000000000c0 RSI: 0000200000000090 RDI: 0000000000000000 RBP: 00007f7cac610a68 R08: 0000200000000140 R09: 0000200000000140 R10: 0000200000000100 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7cac7b5fa0 R15: 00007fffe92d8cd8 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32e910 (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: ffffffff8d32f110 (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: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510 3 locks held by kworker/u4:4/58: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90001597d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263 2 locks held by kworker/1:3/3639: #0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc900032e7d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 2 locks held by getty/4005: #0: ffff8880309b3098 (&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 3 locks held by kworker/1:6/4300: #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90004287d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #2: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 2 locks held by kworker/u4:6/4308: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc900042b7d20 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 2 locks held by kworker/1:10/4593: #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc900034c7d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 3 locks held by kworker/u4:8/4629: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90003547d20 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #2: ffffffff8d333d78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 4 locks held by kworker/u4:9/6392: #0: ffff888017e16938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90003a37d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8e544210 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x166/0xd20 net/core/net_namespace.c:594 #3: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: cangw_pernet_exit_batch+0x1c/0x90 net/can/gw.c:1250 1 lock held by syz-executor/6550: #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3492 7 locks held by syz-executor/7999: #0: ffff88807e34a460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x269/0xbc0 fs/read_write.c:580 #1: ffff888056e4d488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:325 #2: ffff88802772d3a8 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8de61c48 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xf8/0x480 drivers/net/netdevsim/bus.c:209 #4: ffff8880687d60e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #4: ffff8880687d60e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1080 [inline] #4: ffff8880687d60e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb6/0x880 drivers/base/dd.c:1283 #5: ffff88807453a2f8 (&devlink->lock_key#19){+.+.}-{3:3}, at: nsim_drv_remove+0x54/0x160 drivers/net/netdevsim/dev.c:1677 #6: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: unregister_netdevice_notifier_net+0x85/0x390 net/core/dev.c:1928 1 lock held by syz.2.1042/8162: #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: ppp_release+0x86/0x1f0 drivers/net/ppp/ppp_generic.c:417 3 locks held by syz.1.1034/8165: #0: ffffffff8e5b1db0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:860 #1: ffffffff8e5b1c68 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8e5b1c68 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x125/0xf50 net/netlink/genetlink.c:848 #2: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: ieee80211_register_hw+0x2ca4/0x3f10 net/mac80211/main.c:1330 1 lock held by syz.3.1033/8172: #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x4a9/0x2320 drivers/net/tun.c:3104 1 lock held by syz.3.1033/8174: #0: ffffffff8e550d68 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x59c/0xef0 net/core/dev_ioctl.c:612 ============================================= 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: 9 Comm: kworker/u4:0 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:__local_bh_enable_ip+0x58/0x1f0 kernel/softirq.c:381 Code: 49 bc 00 00 00 00 00 fc ff df 48 c7 44 24 20 b3 8a b5 41 48 c7 44 24 28 d3 27 c1 8c 48 c7 44 24 30 00 1b 54 81 48 8d 5c 24 20 <48> c1 eb 03 48 b8 f1 f1 f1 f1 00 f3 f3 f3 4a 89 04 23 65 8b 05 d7 RSP: 0018:ffffc900000e7ac0 EFLAGS: 00000286 RAX: 29610fc8d2109800 RBX: ffffc900000e7ae0 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000201 RDI: ffffffff86636335 RBP: ffffc900000e7b78 R08: dffffc0000000000 R09: ffffed1003a5e6c3 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff888025db6a48 R15: 0000000000000201 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffe8 CR3: 0000000026e54000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x755/0xab0 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