INFO: task syz.5.1541:15826 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.1541 state:D stack:26688 pid:15826 tgid:15824 ppid:12872 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289 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 __super_lock fs/super.c:60 [inline] super_lock+0x2d6/0x3d0 fs/super.c:122 user_get_super+0xc8/0x120 fs/super.c:1001 quotactl_block fs/quota/quota.c:889 [inline] __do_sys_quotactl fs/quota/quota.c:955 [inline] __se_sys_quotactl+0x540/0x9e0 fs/quota/quota.c:917 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: 0033:0x7ffa6135c819 RSP: 002b:00007ffa5f5ae028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007ffa615d5fa0 RCX: 00007ffa6135c819 RDX: 0000000000000000 RSI: 0000200000000000 RDI: ffffffff80000500 RBP: 00007ffa613f2c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000200000000240 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffa615d6038 R14: 00007ffa615d5fa0 R15: 00007ffe66c20fc8 Showing all locks held in the system: 2 locks held by kthreadd/2: #0: ffffffff8de0b130 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x2360/0x3cd0 kernel/fork.c:2322 #1: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: write_lock_irq include/linux/rwlock_rt.h:115 [inline] #1: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: copy_process+0x2482/0x3cd0 kernel/fork.c:2369 1 lock held by pool_workqueue_/3: #0: ffffffff8dc6bb78 (wq_pool_mutex){+.+.}-{4:4}, at: pwq_release_workfn+0x3cc/0x8c0 kernel/workqueue.c:5190 1 lock held by khungtaskd/38: #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:847 [inline] #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by udevd/5166: 2 locks held by getty/5557: #0: ffff88803212d0a0 (&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 3 locks held by kworker/0:3/5804: 1 lock held by udevd/5814: 2 locks held by syz-executor/6626: 2 locks held by syz-executor/13001: 1 lock held by syz-executor/13757: 1 lock held by syz-executor/14140: #0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: read_lock include/linux/rwlock_rt.h:38 [inline] #0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: __do_wait+0xe1/0x740 kernel/exit.c:1678 1 lock held by syz.5.1541/15826: #0: ffff88803b8f20d0 (&type->s_umount_key#83){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88803b8f20d0 (&type->s_umount_key#83){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz-executor/16074: #0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: read_lock include/linux/rwlock_rt.h:38 [inline] #0: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: __do_wait+0xe1/0x740 kernel/exit.c:1678 9 locks held by syz-executor/17593: 6 locks held by syz.3.1855/18070: 2 locks held by syz.0.1857/18079: #0: ffff888075d860d0 (&type->s_umount_key#65/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345 #1: ffffffff8dc6bb78 (wq_pool_mutex){+.+.}-{4:4}, at: apply_wqattrs_lock kernel/workqueue.c:5291 [inline] #1: ffffffff8dc6bb78 (wq_pool_mutex){+.+.}-{4:4}, at: __alloc_workqueue+0x9ef/0x1e90 kernel/workqueue.c:5844 2 locks held by syz.2.1859/18091: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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: 5804 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: events_power_efficient wg_ratelimiter_gc_entries RIP: 0010:__lock_acquire+0x2b4/0x2cf0 kernel/locking/lockdep.c:5170 Code: b8 0b 00 00 83 fd 31 48 89 74 24 18 0f 83 14 28 00 00 48 89 6c 24 28 48 8d 04 ad 00 00 00 00 48 01 e8 89 f1 81 e1 ff 1f 00 00 00 e0 ff ff 41 23 54 c7 20 09 ca 41 89 54 c7 20 4d 89 44 c7 08 RSP: 0018:ffffc900044f7800 EFLAGS: 00000002 RAX: 000000000000000a RBX: 0000000000000000 RCX: 00000000000009f1 RDX: 0000000000000002 RSI: 00000000000009f1 RDI: 0000000000000000 RBP: 0000000000000002 R08: ffffffff85ebe4bd R09: ffffffff8e88e5d8 R10: dffffc0000000000 R11: fffffbfff1ed4f17 R12: 0000000000000000 R13: 0000000000000000 R14: ffff888029ec9e80 R15: ffff888029ecaa38 FS: 0000000000000000(0000) GS:ffff888126332000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8dc44cf000 CR3: 0000000031ae6000 CR4: 00000000003526f0 Call Trace: lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 rt_spin_lock+0x83/0x400 kernel/locking/spinlock_rt.c:56 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:3288 [inline] process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3371 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3452 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