INFO: task syz.5.369:7732 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.369 state:D stack:23880 pid:7732 tgid:7731 ppid:6580 task_flags:0x400140 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 __rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114 rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline] __down_read kernel/locking/rwsem.c:1466 [inline] down_read+0x132/0x200 kernel/locking/rwsem.c:1539 inode_lock_shared include/linux/fs.h:1043 [inline] lookup_slow+0x46/0x70 fs/namei.c:1932 walk_component fs/namei.c:2279 [inline] link_path_walk+0xd1e/0x18d0 fs/namei.c:2647 path_parentat fs/namei.c:2851 [inline] __filename_parentat+0x27f/0x6f0 fs/namei.c:2875 filename_parentat fs/namei.c:2893 [inline] filename_create+0xd9/0x370 fs/namei.c:4903 filename_mkdirat+0xd2/0x520 fs/namei.c:5259 __do_sys_mkdirat fs/namei.c:5287 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5284 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: 0033:0x7f0bfa26b607 RSP: 002b:00007f0bf84c5e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f0bf84c5ee0 RCX: 00007f0bfa26b607 RDX: 00000000000001ff RSI: 0000200000000240 RDI: 00000000ffffff9c RBP: 0000200000000140 R08: 00002000000000c0 R09: 0000000000000000 R10: 0000200000000140 R11: 0000000000000246 R12: 0000200000000240 R13: 00007f0bf84c5ea0 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 4 locks held by ktimers/1/29: 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 2 locks held by getty/5552: #0: ffff88803731f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz.5.369/7732: #0: ffff8880688f1090 (&type->i_mutex_dir_key#3){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline] #0: ffff8880688f1090 (&type->i_mutex_dir_key#3){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1932 5 locks held by syz.5.369/7745: ============================================= NMI backtrace for cpu 0 CPU: 0 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:467 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5954 Comm: kworker/1:7 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:__migrate_enable include/linux/sched.h:2433 [inline] RIP: 0010:migrate_enable include/linux/sched.h:2475 [inline] RIP: 0010:rt_spin_unlock+0xa2/0x200 kernel/locking/spinlock_rt.c:81 Code: c1 e8 03 42 80 3c 38 00 74 05 e8 f9 06 06 f7 4c 89 e8 48 05 b0 04 00 00 49 39 85 a0 04 00 00 0f 85 db 00 00 00 43 0f b6 04 3c <84> c0 0f 85 f5 00 00 00 66 41 c7 06 00 00 65 48 8b 05 60 a3 29 07 RSP: 0018:ffffc90005557a70 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff8e88c680 RCX: ffffffff99595400 RDX: 0000000029c5fe1b RSI: ffffffff8d7b8c0d RDI: ffff888030132320 RBP: 0000000000000001 R08: ffffffff8b2451d0 R09: ffffffff8ddcd780 R10: 0000000000000000 R11: fffffbfff1ed46b7 R12: 1ffff11006026468 R13: ffff888030131e80 R14: ffff888030132340 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888126440000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055653e7c9720 CR3: 000000000dbba000 CR4: 00000000003526f0 Call Trace: spin_unlock include/linux/spinlock_rt.h:109 [inline] wg_ratelimiter_gc_entries+0x3a8/0x480 drivers/net/wireguard/ratelimiter.c:76 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:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245