INFO: task syz-executor:14620 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:22528 pid:14620 tgid:14620 ppid:1 task_flags:0x400140 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+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: 0033:0x7f98bdc2d9d7 RSP: 002b:00007ffee682d428 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f98bdcc2050 RCX: 00007f98bdc2d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffee682d4e0 RBP: 00007ffee682d4e0 R08: 00007ffee682e4e0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffee682e570 R13: 00007f98bdcc2050 R14: 00000000000bef5d R15: 00007ffee682e5b0 INFO: task syz-executor:14748 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:22688 pid:14748 tgid:14748 ppid:1 task_flags:0x400140 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+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: 0033:0x7f339f6dd9d7 RSP: 002b:00007fff3d8612e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f339f772050 RCX: 00007f339f6dd9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff3d8613a0 RBP: 00007fff3d8613a0 R08: 00007fff3d8623a0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff3d862430 R13: 00007f339f772050 R14: 00000000000bfb17 R15: 00007fff3d862470 Showing all locks held in the system: 3 locks held by kworker/1:1/36: #0: ffff888019c07938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff888019c07938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc90000ab7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc90000ab7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 #2: ffff888036cbc260 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490 1 lock held by khungtaskd/38: #0: ffffffff8ddcba00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcba00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcba00 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:15/1505: #0: ffff888032a24938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff888032a24938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc90006227c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc90006227c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 #2: ffffffff8f15b778 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f15b778 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4198 2 locks held by getty/5558: #0: ffff888037c680a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e762e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211 4 locks held by kworker/u8:10/10710: #0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc90005b87c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc90005b87c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 #2: ffffffff8f14cfc0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:675 #3: ffff888084b2e160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #3: ffff888084b2e160 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff888084b2e160 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x11b/0x3f0 net/devlink/core.c:504 2 locks held by syz-executor/14274: #0: ffff888065ae60d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888065ae60d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888065ae60d0 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24db18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/14620: #0: ffff8880704be0d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880704be0d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880704be0d0 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24db18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/14748: #0: ffff8880536760d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880536760d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880536760d0 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24db18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/15306: #0: ffff8880332200d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880332200d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880332200d0 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24db18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/15388: #0: ffff8880284640d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880284640d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880284640d0 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24db18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/15444: #0: ffff8880331520d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880331520d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880331520d0 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24db18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/15892: #0: ffff888028c680d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888028c680d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888028c680d0 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24db18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 1 lock held by syz.3.995/15948: #0: ffff888065ae60d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff888065ae60d0 (&type->s_umount_key#96){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 2 locks held by syz-executor/16107: #0: ffff88803519a0d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88803519a0d0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88803519a0d0 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24db18 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 1 lock held by syz-executor/16571: 10 locks held by syz-executor/16597: 5 locks held by syz.1.1075/16766: 1 lock held by dhcpcd-run-hook/16769: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 16597 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:__bfs_next kernel/locking/lockdep.c:1699 [inline] RIP: 0010:__bfs kernel/locking/lockdep.c:1752 [inline] RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline] RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline] RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline] RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline] RIP: 0010:__lock_acquire+0x17a0/0x2cf0 kernel/locking/lockdep.c:5237 Code: 05 bd e6 b6 13 48 b8 00 00 00 00 01 00 00 00 48 89 05 a4 e6 b6 13 48 8d 84 24 90 00 00 00 48 89 05 95 66 b6 13 31 ff 45 31 e4 <4d> 85 e4 4c 8b 6c 24 10 74 30 49 8b 44 24 30 48 85 c0 74 26 48 8b RSP: 0018:ffffc90003bbf120 EFLAGS: 00000046 RAX: ffffffff92fd6a90 RBX: 00000000000003cc RCX: 0000000000102011 RDX: ffffffff95ffca98 RSI: ffff88802cb88cf8 RDI: 00000000000003cc RBP: 10b73957cad983e7 R08: ffffc90003bbf0e8 R09: 0000000000000020 R10: dffffc0000000000 R11: ffffffff81a0a510 R12: ffffffff95e7cc18 R13: ffff88802cb88d48 R14: ffff88802cb88000 R15: 0000000000000054 FS: 000055555e6ab500(0000) GS:ffff888126439000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31930000 CR3: 0000000028f9a000 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] get_from_partial_node+0x54/0x480 mm/slub.c:3810 get_from_partial mm/slub.c:3938 [inline] ___slab_alloc+0xae/0x660 mm/slub.c:4409 __slab_alloc_node mm/slub.c:4479 [inline] slab_alloc_node mm/slub.c:4854 [inline] kmem_cache_alloc_noprof+0xea/0x680 mm/slub.c:4873 kmem_alloc_batch lib/debugobjects.c:371 [inline] fill_pool+0x156/0x590 lib/debugobjects.c:420 debug_objects_fill_pool+0x97/0xd0 lib/debugobjects.c:742 debug_object_activate+0x36/0x520 lib/debugobjects.c:831 debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline] __call_rcu_common kernel/rcu/tree.c:3116 [inline] call_rcu+0x43/0x890 kernel/rcu/tree.c:3251 __dentry_kill+0x469/0x5e0 fs/dcache.c:689 finish_dput+0xc9/0x480 fs/dcache.c:879 find_next_child+0x1e5/0x250 fs/libfs.c:594 __simple_recursive_removal+0x10b/0x520 fs/libfs.c:611 debugfs_remove+0x5b/0x70 fs/debugfs/inode.c:781 nsim_dev_port_debugfs_exit drivers/net/netdevsim/dev.c:444 [inline] __nsim_dev_port_del+0x173/0x1b0 drivers/net/netdevsim/dev.c:1529 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1540 [inline] nsim_dev_reload_destroy+0x288/0x490 drivers/net/netdevsim/dev.c:1764 nsim_drv_remove+0x58/0x160 drivers/net/netdevsim/dev.c:1779 device_remove drivers/base/dd.c:631 [inline] __device_release_driver drivers/base/dd.c:1344 [inline] device_release_driver_internal+0x46f/0x870 drivers/base/dd.c:1367 bus_remove_device+0x45a/0x570 drivers/base/bus.c:657 device_del+0x52b/0x900 drivers/base/core.c:3880 device_unregister+0x21/0xf0 drivers/base/core.c:3921 nsim_bus_dev_del drivers/net/netdevsim/bus.c:491 [inline] del_device_store+0x2b0/0x370 drivers/net/netdevsim/bus.c:244 kernfs_fop_write_iter+0x3b0/0x540 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x629/0xba0 fs/read_write.c:688 ksys_write+0x156/0x270 fs/read_write.c:740 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: 0033:0x7f503a05cfce Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007ffc6b7ac578 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000055555e6ab500 RCX: 00007f503a05cfce RDX: 0000000000000001 RSI: 00007ffc6b7ac600 RDI: 0000000000000005 RBP: 00007f503a13351c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc6b7ac600 R14: 00007f503ae44620 R15: 0000000000000003