INFO: task syz-executor:29306 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:21440 pid:29306 tgid:29306 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: 0033:0x7f22e6cbda57 RSP: 002b:00007ffd969c04a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f22e6d52048 RCX: 00007f22e6cbda57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd969c0560 RBP: 00007ffd969c0560 R08: 00007ffd969c1560 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd969c15f0 R13: 00007f22e6d52048 R14: 00000000000d3eb3 R15: 00007ffd969c1630 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 9 locks held by kworker/u8:10/1421: 4 locks held by kworker/u8:11/1491: 2 locks held by getty/5554: #0: ffff88803700d0a0 (&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 3 locks held by kworker/0:4/5800: 3 locks held by kworker/1:1/26943: #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: ffffc90006de7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc90006de7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 #2: ffff88803ad0e260 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490 2 locks held by syz-executor/28581: #0: ffff888034cb20d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888034cb20d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888034cb20d0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24e4d8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 3 locks held by syz.9.942/29170: #0: ffff88807859ff28 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1261 #1: ffff8880557a0480 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2710 [inline] #1: ffff8880557a0480 (sb_writers#3){.+.+}-{0:0}, at: vfs_writev+0x2b0/0x9a0 fs/read_write.c:1057 #2: ffff888034cb20d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #2: ffff888034cb20d0 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 2 locks held by syz-executor/29306: #0: ffff88801a7200d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88801a7200d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88801a7200d0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24e4d8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/29731: #0: ffff88806eb060d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88806eb060d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88806eb060d0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24e4d8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/31436: #0: ffff88805c5fc0d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805c5fc0d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88805c5fc0d0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e24e4d8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 1 lock held by syz.5.1091/866: #0: ffff888034cb20d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff888034cb20d0 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 2 locks held by syz.8.1103/1022: #0: ffff8880624b80d0 (&type->s_umount_key#55){++++}-{4:4}, at: do_remount fs/namespace.c:3388 [inline] #0: ffff8880624b80d0 (&type->s_umount_key#55){++++}-{4:4}, at: path_mount+0xd7d/0x10e0 fs/namespace.c:4151 #1: ffffffff8e24e4d8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogOpen+0xca/0xfa0 fs/jfs/jfs_logmgr.c:1071 9 locks held by syz-executor/1724: 1 lock held by syz.7.1186/2821: #0: ffff888034cb20d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff888034cb20d0 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.6.1253/3719: #0: ffff88806eb060d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88806eb060d0 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 2 locks held by syz-executor/3973: #0: ffffffff8e8b80e8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e8b80e8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e8b80e8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f15cb38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f15cb38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f15cb38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4093 2 locks held by syz-executor/4076: #0: ffffffff8f6c2be0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8f6c2be0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8f6c2be0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f15cb38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f15cb38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f15cb38 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4093 2 locks held by syz.3.1292/4124: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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: 1491 Comm: kworker/u8:11 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: bat_events batadv_dat_purge RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:146 [inline] RIP: 0010:__local_bh_enable_ip+0x26/0x2b0 kernel/softirq.c:260 Code: 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 89 f3 65 8b 05 69 b0 c6 10 a9 ff ff ff 7f 74 05 45 31 ff eb 0b 9c 41 5f <41> c1 ef 09 41 83 e7 01 65 8b 05 4b b0 c6 10 a9 00 00 0f 00 0f 85 RSP: 0018:ffffc900063f7a30 EFLAGS: 00000246 RAX: 0000000080000000 RBX: 0000000000000200 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000200 RDI: ffffffff8aed483e RBP: 0000000000000400 R08: ffffffff8f6a6ab7 R09: 1ffffffff1ed4d56 R10: dffffc0000000000 R11: fffffbfff1ed4d57 R12: ffffffff8aed4ba0 R13: ffff8880357be488 R14: ffff888059a49558 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff888126336000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5e188756b8 CR3: 000000003faae000 CR4: 00000000003526f0 Call Trace: local_bh_enable include/linux/bottom_half.h:33 [inline] spin_unlock_bh include/linux/spinlock_rt.h:116 [inline] __batadv_dat_purge+0x344/0x400 net/batman-adv/distributed-arp-table.c:185 batadv_dat_purge+0x20/0x70 net/batman-adv/distributed-arp-table.c:204 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