INFO: task syz.4.121:6581 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.121 state:D stack:28128 pid:6581 tgid:6570 ppid:5796 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6908 __schedule_loop kernel/sched/core.c:6990 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7286 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244 inode_lock_nested include/linux/fs.h:1073 [inline] __start_dirop fs/namei.c:2923 [inline] start_dirop fs/namei.c:2934 [inline] filename_create+0x200/0x370 fs/namei.c:4922 filename_mknodat+0x18c/0x670 fs/namei.c:5130 __do_sys_mknod fs/namei.c:5179 [inline] __se_sys_mknod+0x3a/0x150 fs/namei.c:5176 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f91daacc799 RSP: 002b:00007f91d8cfd028 EFLAGS: 00000246 ORIG_RAX: 0000000000000085 RAX: ffffffffffffffda RBX: 00007f91dad46090 RCX: 00007f91daacc799 RDX: 0000000000000709 RSI: 0000000000002000 RDI: 0000200000000000 RBP: 00007f91dab62bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f91dad46128 R14: 00007f91dad46090 R15: 00007ffd2c7d26d8 Showing all locks held in the system: 1 lock held by khungtaskd/37: #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:7/528: #0: ffff88801f6e7138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88801f6e7138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc90004377c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc90004377c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 #2: ffff88803689a0d0 (&type->s_umount_key#103){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565 #3: ffff888061a0c628 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108 6 locks held by kworker/u8:9/1393: 3 locks held by kworker/u8:13/1533: #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc900065dfc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc900065dfc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 #2: ffffffff8f15bdb8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313 4 locks held by kworker/u8:14/3101: #0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc9000e617c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc9000e617c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 #2: ffffffff8f14d600 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:675 #3: ffffffff8f15bdb8 (rtnl_mutex){+.+.}-{4:4}, at: fib_net_exit_batch+0x22/0xf0 net/ipv4/fib_frontend.c:1676 1 lock held by udevd/5165: 2 locks held by getty/5551: #0: ffff888032e8c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by udevd/5797: 3 locks held by kworker/0:3/5805: 1 lock held by udevd/5806: 4 locks held by syz.4.121/6571: 2 locks held by syz.4.121/6581: #0: ffff88803689a480 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff888061a0c9f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff888061a0c9f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline] #1: ffff888061a0c9f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline] #1: ffff888061a0c9f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4922 10 locks held by syz-executor/6730: 1 lock held by udevd/8232: 8 locks held by syz-executor/8260: 5 locks held by syz.3.371/8568: 4 locks held by syz.0.375/8589: 2 locks held by dhcpcd-run-hook/8593: 4 locks held by syz.5.374/8596: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5805 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_power_efficient wg_ratelimiter_gc_entries RIP: 0010:lockdep_hardirqs_on_prepare+0x6/0x260 kernel/locking/lockdep.c:4363 Code: 00 00 10 00 e8 0b 62 fa 02 89 c0 e9 14 18 86 09 cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 <41> 56 41 54 53 83 3d 2e 67 ca 0d 00 0f 84 95 01 00 00 65 8b 05 71 RSP: 0018:ffffc900046f79b0 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000246 RCX: 0000000080000003 RDX: 0000000000000000 RSI: ffffffff8ba64ce0 RDI: ffffffff8ba64ca0 RBP: ffffc900046f7a98 R08: ffffffff8f6a4eb7 R09: 1ffffffff1ed49d6 R10: dffffc0000000000 R11: fffffbfff1ed49d7 R12: 1ffff920008def45 R13: 0000000000000246 R14: ffffffff8e88dbc0 R15: ffffc900046f7a20 FS: 0000000000000000(0000) GS:ffff88812633d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb8de9856b8 CR3: 0000000033264000 CR4: 00000000003526f0 Call Trace: trace_hardirqs_on+0x28/0x40 kernel/trace/trace_preemptirq.c:78 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline] _raw_spin_unlock_irqrestore+0x30/0x80 kernel/locking/spinlock.c:194 raw_spin_unlock_irqrestore_wake include/linux/sched/wake_q.h:97 [inline] rtlock_slowlock kernel/locking/rtmutex.c:1896 [inline] rtlock_lock kernel/locking/spinlock_rt.c:43 [inline] __rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline] rt_spin_lock+0x17a/0x400 kernel/locking/spinlock_rt.c:57 spin_lock include/linux/spinlock_rt.h:45 [inline] wg_ratelimiter_gc_entries+0x5d/0x480 drivers/net/wireguard/ratelimiter.c:63 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245