INFO: task syz-executor:21819 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21312 pid:21819 tgid:21819 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1539/0x5110 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 __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: 0033:0x7fa35bf9c117 RSP: 002b:00007ffd5cc16268 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fa35c00471f RCX: 00007fa35bf9c117 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd5cc16320 RBP: 00007ffd5cc16320 R08: 00007ffd5cc17320 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd5cc173b0 R13: 00007fa35c00471f R14: 000000000016b979 R15: 00007ffd5cc173f0 INFO: task syz-executor:27318 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21328 pid:27318 tgid:27318 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1539/0x5110 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 __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: 0033:0x7ffbc339c117 RSP: 002b:00007ffdf5e45b08 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007ffbc340471f RCX: 00007ffbc339c117 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdf5e45bc0 RBP: 00007ffdf5e45bc0 R08: 00007ffdf5e46bc0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdf5e46c50 R13: 00007ffbc340471f R14: 000000000017a77d R15: 00007ffdf5e46c90 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e760160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e760160 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e760160 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5576: #0: ffff8880376380a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036b62f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:3/5876: #0: ffff88801b06b548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254 #1: ffffc9000487fc40 ((work_completion)(&blkg->free_work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255 #2: ffffffff8e7663f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #2: ffffffff8e7663f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 2 locks held by syz-executor/21819: #0: ffff88807e65e0e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] ffff88807e65e0e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] ffff88807e65e0e0 (&type->s_umount_key#86){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebe8088 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 3 locks held by kworker/u8:11/22652: #0: ffff8880b863ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffffffff8e760160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #2: ffffffff8e760160 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #2: ffffffff8e760160 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1193 [inline] #2: ffffffff8e760160 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa5/0x23c0 arch/x86/kernel/unwind_orc.c:495 5 locks held by kworker/u8:15/22654: #0: ffff88801c2ae948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254 #1: ffffc9000ac7fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255 #2: ffffffff8fbb7150 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xfe/0x7b0 net/core/net_namespace.c:670 #3: ffff888032619528 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_destruct+0x116/0x310 drivers/net/wireguard/device.c:249 #4: ffffffff8e7662c0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828 2 locks held by syz-executor/23857: #0: ffff88805ba500e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805ba500e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88805ba500e0 (&type->s_umount_key#86){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebe8088 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/26890: #0: ffff888022b480e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888022b480e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888022b480e0 (&type->s_umount_key#86){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebe8088 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/27181: #0: ffff888055a0e0e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888055a0e0e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888055a0e0e0 (&type->s_umount_key#86){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebe8088 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/27318: #0: ffff8880605a60e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880605a60e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880605a60e0 (&type->s_umount_key#86){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebe8088 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/27409: #0: ffff8880777240e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880777240e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880777240e0 (&type->s_umount_key#86){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebe8088 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/27487: #0: ffff88805f0140e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805f0140e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88805f0140e0 (&type->s_umount_key#86){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebe8088 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/27932: #0: ffff88805692a0e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805692a0e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88805692a0e0 (&type->s_umount_key#86){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebe8088 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/28354: #0: ffff8880557fe0e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880557fe0e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880557fe0e0 (&type->s_umount_key#86){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8ebe8088 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 1 lock held by syz.1.6652/29571: #0: ffff88805ba500e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805ba500e0 (&type->s_umount_key#86){++++}-{4:4}, at: super_lock+0x289/0x3d0 fs/super.c:122 4 locks held by syz-executor/29707: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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:347 [inline] watchdog+0x103d/0x1090 kernel/hung_task.c:516 kthread+0x388/0x470 kernel/kthread.c:467 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: 6849 Comm: kworker/u8:13 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210 Code: 89 fb e8 23 00 00 00 48 8b 3d 44 93 54 0c 48 89 de 5b e9 03 1f 5e 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0d 68 43 55 11 65 8b 15 89 43 55 RSP: 0018:ffffc9001bcd7938 EFLAGS: 00000283 RAX: 0000000000000400 RBX: 00000000000000d5 RCX: 0000000000000046 RDX: 0000000000000003 RSI: ffffffff8e15a2f5 RDI: ffff888031995ac0 RBP: ffffc9001bcd7a90 R08: ffffffff8b74268a R09: ffffffff8e760160 R10: dffffc0000000000 R11: ffffed1006bdbf17 R12: ffff88806b660900 R13: ffff88806b660910 R14: dffffc0000000000 R15: ffff888088eec6a0 FS: 0000000000000000(0000) GS:ffff888125472000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f85babe0ad8 CR3: 0000000075766000 CR4: 00000000003526f0 DR0: 000000000000005a DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:758 [inline] batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:833 [inline] batadv_iv_ogm_schedule+0x746/0xf50 net/batman-adv/bat_iv_ogm.c:873 batadv_iv_send_outstanding_bat_ogm_packet+0x6c8/0x7e0 net/batman-adv/bat_iv_ogm.c:1709 process_one_work+0x949/0x1650 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0xb46/0x1140 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess): 0: 89 fb mov %edi,%ebx 2: e8 23 00 00 00 call 0x2a 7: 48 8b 3d 44 93 54 0c mov 0xc549344(%rip),%rdi # 0xc549352 e: 48 89 de mov %rbx,%rsi 11: 5b pop %rbx 12: e9 03 1f 5e 00 jmp 0x5e1f1a 17: cc int3 18: cc int3 19: cc int3 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 90 nop 24: 90 nop 25: 90 nop 26: 90 nop 27: 90 nop 28: 90 nop 29: 90 nop * 2a: f3 0f 1e fa endbr64 <-- trapping instruction 2e: 48 8b 04 24 mov (%rsp),%rax 32: 65 48 8b 0d 68 43 55 mov %gs:0x11554368(%rip),%rcx # 0x115543a2 39: 11 3a: 65 gs 3b: 8b .byte 0x8b 3c: 15 .byte 0x15 3d: 89 43 55 mov %eax,0x55(%rbx)