INFO: task syz.1.8542:2468 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.8542 state:D stack:26880 pid:2468 tgid:2463 ppid:19809 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5352 [inline] __schedule+0x165c/0x5560 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7047 [inline] schedule+0x164/0x360 kernel/sched/core.c:7062 super_lock+0x1e0/0x3d0 fs/super.c:116 __iterate_supers+0x126/0x250 fs/super.c:926 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl+0x3a7/0x9e0 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: 0033:0x7fccdad9c799 RSP: 002b:00007fccdbc06028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007fccdb015fa0 RCX: 00007fccdad9c799 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102 RBP: 00007fccdae32c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fccdb016038 R14: 00007fccdb015fa0 R15: 00007ffd220db128 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e95d7e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e95d7e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e95d7e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by udevd/5210: 2 locks held by getty/5599: #0: ffff8880377110a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211 1 lock held by syz.0.7157/20999: 2 locks held by kworker/1:9/24221: #0: ffff88813ff43140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x890/0x1710 kernel/workqueue.c:3260 #1: ffffc90012f57c40 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x8b7/0x1710 kernel/workqueue.c:3261 1 lock held by syz.4.7877/29021: #0: ffff8880422620d8 (&type->s_umount_key#91/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xab0 fs/super.c:345 1 lock held by syz-executor/29602: 1 lock held by syz-executor/29609: #0: ffffffff8fdf6540 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8fdf6540 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436 1 lock held by syz.3.8074/31806: #0: ffffffff8e963a28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #0: ffffffff8e963a28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 1 lock held by syz-executor/3020: 5 locks held by syz-executor/3027: #0: ffff8880952c0ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline] #0: ffff8880952c0ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716 #1: ffff8880952c00b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346 #2: ffffffff8ff82900 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline] #2: ffffffff8ff82900 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2644 #3: ffff888037111af8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 net/bluetooth/l2cap_core.c:1774 #4: ffffffff8e963a28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #4: ffffffff8e963a28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP 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:162 [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:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 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: 30796 Comm: kworker/u8:7 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: bat_events batadv_tt_purge RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3801 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3821 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3876 [inline] RIP: 0010:__lock_acquire+0xb17/0x2cf0 kernel/locking/lockdep.c:5237 Code: db 94 0e 48 c7 c6 07 09 18 8e 67 48 0f b9 3a 90 48 bb eb 83 b5 80 46 86 c8 61 48 0f af dd 48 c1 eb 2d 48 8b 04 dd 60 a3 06 94 <48> 85 c0 0f 94 c1 48 83 c0 f8 0f 94 c2 08 ca 0f 84 1c 01 00 00 e8 RSP: 0018:ffffc90004adf478 EFLAGS: 00000007 RAX: ffffffff949b68b8 RBX: 000000000000edc6 RCX: 0000000000040000 RDX: 00000000ab0c3346 RSI: 00000000e1dc148c RDI: ffff88802b649e80 RBP: cf6d8e996d0f470a R08: ffffffff8194f241 R09: ffff8880b843ae60 R10: dffffc0000000000 R11: fffffbfff206889f R12: ffff88802b64aa20 R13: ffff88802b64aa20 R14: ffff88802b649e80 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff888124ff3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffda9d29928 CR3: 000000000e74a000 CR4: 00000000003526f0 DR0: 0000000000000006 DR1: 1000000000000004 DR2: 000000007fffdffd DR3: 0000800000000005 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 _raw_spin_lock_nested+0x32/0x50 kernel/locking/spinlock.c:382 raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 raw_spin_rq_lock kernel/sched/sched.h:1620 [inline] rq_lock kernel/sched/sched.h:1957 [inline] __schedule+0x3a6/0x5560 kernel/sched/core.c:6865 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7292 irqentry_exit+0x5e4/0x700 kernel/entry/common.c:240 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:104 [inline] RIP: 0010:__local_bh_enable_ip+0xd8/0x130 kernel/softirq.c:457 Code: 8b e8 cc eb 32 0a 65 66 8b 05 8c cc b9 11 66 85 c0 75 32 bf 01 00 00 00 e8 55 f1 0b 00 e8 10 ac 45 00 fb 65 8b 05 68 cc b9 11 <85> c0 75 05 e8 7f 07 ab ff 5b 41 5e e9 07 bc 35 0a cc 90 0f 0b 90 RSP: 0018:ffffc90004adfa10 EFLAGS: 00000202 RAX: 0000000080000000 RBX: 0000000000000201 RCX: 0000000000000046 RDX: 0000000000000006 RSI: ffffffff8e05f4c1 RDI: ffffffff8c2a8e80 RBP: ffff88805a199098 R08: ffffffff903444f7 R09: 1ffffffff206889e R10: dffffc0000000000 R11: fffffbfff206889f R12: ffff888021698288 R13: dffffc0000000000 R14: ffffffff8b8a7ad7 R15: ffff88807b43dcd0 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_tt_local_purge+0x2a7/0x340 net/batman-adv/translation-table.c:1315 batadv_tt_purge+0x35/0x9e0 net/batman-adv/translation-table.c:3509 process_one_work+0x9a3/0x1710 kernel/workqueue.c:3288 process_scheduled_works kernel/workqueue.c:3379 [inline] worker_thread+0xba8/0x11e0 kernel/workqueue.c:3465 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