INFO: task syz.4.158:7029 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.158 state:D stack:27112 pid:7029 tgid:6997 ppid:5796 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x147b/0x4f50 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 io_schedule+0x80/0xe0 kernel/sched/core.c:7791 TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline] txBegin+0x27d/0xc00 fs/jfs/jfs_txnmgr.c:375 jfs_create+0x216/0xb10 fs/jfs/namei.c:98 lookup_open fs/namei.c:4449 [inline] open_last_lookups fs/namei.c:4549 [inline] path_openat+0x1902/0x3e70 fs/namei.c:4793 do_filp_open+0x22d/0x490 fs/namei.c:4823 do_sys_openat2+0x12f/0x220 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5d80efacb9 RSP: 002b:00007f5d7f135028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f5d81176090 RCX: 00007f5d80efacb9 RDX: 00000000000a4c42 RSI: 0000200000000180 RDI: ffffffffffffff9c RBP: 00007f5d80f68bf7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000188 R11: 0000000000000246 R12: 0000000000000000 R13: 0000[ 337.126907][ T39] R13: 00007f5d81176128 R14: 00007f5d81176090 R15: 00007ffd255ec158 Showing all locks held in the system: 4 locks held by kworker/u8:2/37: 1 lock held by khungtaskd/39: #0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:10/1396: #0: ffff88813fe29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813fe29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc9000534fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000534fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 9 locks held by kworker/u8:14/5025: 1 lock held by udevd/5167: 2 locks held by getty/5551: #0: ffff88803143b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by udevd/5809: 3 locks held by kworker/u8:16/5943: #0: ffff888027d76138 ((wq_completion)loop5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888027d76138 ((wq_completion)loop5){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc900051cfbc0 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc900051cfbc0 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff88802497c160 (&lo->lo_work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:93 [inline] #2: ffff88802497c160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_process_work+0x125/0x11b0 drivers/block/loop.c:1975 2 locks held by udevd/6621: 2 locks held by syz.4.158/7029: #0: ffff888060946480 (sb_writers#23){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499 #1: ffff88805f6cc9f8 (&type->i_mutex_dir_key#17){++++}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff88805f6cc9f8 (&type->i_mutex_dir_key#17){++++}-{4:4}, at: open_last_lookups fs/namei.c:4546 [inline] #1: ffff88805f6cc9f8 (&type->i_mutex_dir_key#17){++++}-{4:4}, at: path_openat+0xb65/0x3e70 fs/namei.c:4793 1 lock held by syz-executor/8806: #0: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071 3 locks held by kworker/1:9/8858: #0: ffff88813fe15138 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813fe15138 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90021a07bc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90021a07bc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffffffff8ed37e78 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 5 locks held by dhcpcd-run-hook/8882: #0: ffff888063fc3d08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:259 #1: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #1: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #1: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: ___pte_offset_map+0x29/0x200 mm/pgtable-generic.c:288 #2: ffff888033cd2598 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline] #2: ffff888033cd2598 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: __pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:403 #3: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #3: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #3: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #3: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 #4: ffff8880b8833cd0 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline] #4: ffff8880b8833cd0 ((lock)#2){+.+.}-{3:3}, at: __folio_batch_add_and_move+0x283/0xa90 mm/swap.c:-1 4 locks held by syz.1.463/8895: 1 lock held by udevadm/8894: 5 locks held by syz.5.465/8907: 1 lock held by syz.3.466/8913: 5 locks held by syz-executor/8916: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 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+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5025 Comm: kworker/u8:14 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet RIP: 0010:__dev_queue_xmit+0x59c/0x3370 net/core/dev.c:4794 Code: f6 f8 4c 89 ff 4c 89 f6 48 8b 54 24 30 e8 1c f7 ff ff 49 89 c5 4c 89 6c 24 30 49 8d 5d 10 48 89 d8 48 c1 e8 03 42 80 3c 20 00 <74> 08 48 89 df e8 ea 7c 59 f9 4c 8b 2b e8 92 db 24 02 41 89 c6 31 RSP: 0018:ffffc900105ef680 EFLAGS: 00000246 RAX: 1ffff1100ba4a702 RBX: ffff88805d253810 RCX: ffff888034f73c80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900105ef960 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000008 R12: dffffc0000000000 R13: ffff88805d253800 R14: ffff888037622640 R15: ffff88805d2d2000 FS: 0000000000000000(0000) GS:ffff8881267fc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffdf46edd58 CR3: 0000000061a62000 CR4: 00000000003526f0 Call Trace: dev_queue_xmit include/linux/netdevice.h:3381 [inline] batadv_send_skb_packet+0x418/0x690 net/batman-adv/send.c:100 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:391 [inline] batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x631/0x7e0 net/batman-adv/bat_iv_ogm.c:1697 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0x89f/0xd90 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246