INFO: task syz-executor:11228 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-executor state:D stack:22408 pid:11228 tgid:11228 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x15dd/0x52d0 kernel/sched/core.c:6908 __schedule_loop kernel/sched/core.c:6990 [inline] schedule+0x164/0x360 kernel/sched/core.c:7005 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7062 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 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: 0033:0x7f517b59d9d7 RSP: 002b:00007ffe0367cbd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f517b632050 RCX: 00007f517b59d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe0367cc90 RBP: 00007ffe0367cc90 R08: 00007ffe0367dc90 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe0367dd20 R13: 00007f517b632050 R14: 0000000000085b9b R15: 00007ffe0367dd60 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by udevd/5187: 2 locks held by getty/5574: #0: ffff888036b320a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 5 locks held by kworker/u8:27/6076: 2 locks held by syz-executor/11192: #0: ffff88807b6340e0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807b6340e0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88807b6340e0 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebecba8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/11228: #0: ffff88807caea0e0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807caea0e0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88807caea0e0 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebecba8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/11336: #0: ffff888052e1c0e0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888052e1c0e0 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888052e1c0e0 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebecba8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 1 lock held by syz-executor/11861: 2 locks held by syz.6.1553/13397: #0: ffff888050bd20e0 (&type->s_umount_key#52/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xab0 fs/super.c:345 #1: ffffffff8ebecba8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 ============================================= NMI backtrace for cpu 0 CPU: 0 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: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: 6076 Comm: kworker/u8:27 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: events_unbound nsim_dev_trap_report_work RIP: 0010:__bfs kernel/locking/lockdep.c:1753 [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+0x1821/0x2cf0 kernel/locking/lockdep.c:5237 Code: 00 0f 83 8a 01 00 00 4e 8b 24 fd e0 58 24 96 ff c0 25 ff 0f 00 00 89 05 4d 34 83 14 4d 85 e4 0f 84 b2 01 00 00 49 8b 44 24 10 <48> 85 c0 0f 84 1c 0d 00 00 8b 0d 38 34 83 14 39 48 5c 0f 84 67 ff RSP: 0018:ffffc90004a375a0 EFLAGS: 00000082 RAX: ffffffff93ce0aa8 RBX: 00000000000003fd RCX: ffffffff96c0fda8 RDX: ffffffff96c09668 RSI: ffff88803082e7a0 RDI: 00000000000003fd RBP: a4a17a1440d8f04a R08: ffffc90004a37568 R09: 0000000000000020 R10: dffffc0000000000 R11: ffffffff81a1f700 R12: ffffffff96c0fda8 R13: ffff88803082e7a0 R14: ffff88803082db80 R15: 0000000000000571 FS: 0000000000000000(0000) GS:ffff888125560000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2b45be92f8 CR3: 000000002a390000 CR4: 0000000000350ef0 Call Trace: lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162 debug_object_activate+0x83/0x580 lib/debugobjects.c:835 debug_timer_activate kernel/time/timer.c:793 [inline] __mod_timer+0xa4f/0xf30 kernel/time/timer.c:1124 queue_delayed_work_on+0x11a/0x1e0 kernel/workqueue.c:2574 slab_free_hook mm/slub.c:2616 [inline] slab_free mm/slub.c:6165 [inline] kfree+0x13a/0x630 mm/slub.c:6483 skb_kfree_head net/core/skbuff.c:1089 [inline] skb_free_head net/core/skbuff.c:1101 [inline] skb_release_data+0x6f0/0x940 net/core/skbuff.c:1128 skb_release_all net/core/skbuff.c:1203 [inline] __kfree_skb+0x5d/0x210 net/core/skbuff.c:1217 nsim_dev_trap_report drivers/net/netdevsim/dev.c:892 [inline] nsim_dev_trap_report_work+0x7cf/0xb80 drivers/net/netdevsim/dev.c:922 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