INFO: task syz-executor:12934 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21976 pid:12934 tgid:12934 ppid:1 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+0x508/0x680 kernel/locking/rtmutex.c:1647 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline] rt_mutex_slowlock+0x2dc/0x7b0 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline] mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:552 lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 jfs_umount+0x2ef/0x3c0 fs/jfs/jfs_umount.c:114 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x13d/0x2d0 fs/super.c:646 kill_block_super+0x44/0x90 fs/super.c:1725 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f51dfb8d9d7 RSP: 002b:00007fff4305b758 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f51dfc22050 RCX: 00007f51dfb8d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff4305b810 RBP: 00007fff4305b810 R08: 00007fff4305c810 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff4305c8a0 R13: 00007f51dfc22050 R14: 00000000000aa5cf R15: 00007fff4305c8e0 Showing all locks held in the system: 1 lock held by khungtaskd/37: #0: ffffffff8ddcb8c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcb8c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcb8c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by dhcpcd/5457: 2 locks held by getty/5552: #0: ffff888036e770a0 (&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/u8:4/9906: 8 locks held by kworker/0:0/11635: 2 locks held by syz-executor/12796: #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24da18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by kworker/u8:14/12842: #0: ffff88801b316138 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff88801b316138 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc900072e7c40 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc900072e7c40 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 2 locks held by syz-executor/12934: #0: ffff888026c220d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888026c220d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888026c220d0 (&type->s_umount_key#121){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24da18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 1 lock held by syz.3.1084/13128: #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 2 locks held by syz-executor/13334: #0: ffff8880646f40d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880646f40d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880646f40d0 (&type->s_umount_key#121){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24da18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/13558: #0: ffff88802807e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88802807e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88802807e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24da18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/13873: #0: ffff8880359000d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880359000d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880359000d0 (&type->s_umount_key#121){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24da18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 1 lock held by syz.4.1190/14228: #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.4.1190/14229: #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.4.1190/14231: #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.4.1190/14232: #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.2.1323/15081: #0: ffff888026c220d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff888026c220d0 (&type->s_umount_key#121){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 2 locks held by syz.8.1387/15543: #0: ffff88802a5060d0 (&type->s_umount_key#120/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345 #1: ffffffff8e24da18 (jfs_log_mutex){+.+.}-{4:4}, at: open_dummy_log fs/jfs/jfs_logmgr.c:1191 [inline] #1: ffffffff8e24da18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogOpen+0x1a1/0xfa0 fs/jfs/jfs_logmgr.c:1066 1 lock held by syz.5.1401/15634: #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88803903e0d0 (&type->s_umount_key#121){++++}-{4:4}, at: super_lock+0x289/0x3d0 fs/super.c:122 3 locks held by syz-executor/15713: #0: ffffffff8f1c8f60 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8f1c8d58 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline] #1: ffffffff8f1c8d58 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline] #1: ffffffff8f1c8d58 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208 #2: ffffffff8f15a9b8 (rtnl_mutex){+.+.}-{4:4}, at: wg_set_device_doit+0x170/0x2070 drivers/net/wireguard/netlink.c:484 3 locks held by syz.3.1420/15769: ============================================= 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: 11635 Comm: kworker/0:0 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 neigh_periodic_work RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:417 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 e9 2b 70 0c f6 cc RSP: 0018:ffffc900047d78c8 EFLAGS: 00000002 RAX: 0000000000000000 RBX: ffff88805d353d00 RCX: 0000000080000001 RDX: 0000000000000002 RSI: ffffffff8d5606f0 RDI: ffffffff8ba66600 RBP: ffffc900047d7a18 R08: ffffffff8f6a3cb7 R09: 1ffffffff1ed4796 R10: dffffc0000000000 R11: fffffbfff1ed4797 R12: 1ffff920008faf30 R13: 0000000000000246 R14: ffffffff8b265630 R15: ffff88805d353d00 FS: 0000000000000000(0000) GS:ffff88812633c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f38c0469e80 CR3: 0000000032056000 CR4: 00000000003526f0 Call Trace: lockdep_hardirqs_on+0x7a/0x110 kernel/locking/lockdep.c:4472 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline] _raw_spin_unlock_irqrestore+0x30/0x80 kernel/locking/spinlock.c:194 rwbase_write_lock+0x5b6/0x7f0 kernel/locking/rwbase_rt.c:281 rt_write_lock+0x7a/0x220 kernel/locking/spinlock_rt.c:243 write_lock include/linux/rwlock_rt.h:92 [inline] neigh_periodic_work+0x46a/0xe90 net/core/neighbour.c:1008 process_one_work kernel/workqueue.c:3276 [inline] process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440 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