INFO: task syz.7.297:8290[ 536.165362][ T38] INFO: task syz.7.297:8290 blocked in I/O wait for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.297 state:D stack:27496 pid:8290 tgid:8265 ppid:7722 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x16dc/0x5500 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 io_schedule+0x80/0xe0 kernel/sched/core.c:8150 TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline] txBegin+0x281/0xbe0 fs/jfs/jfs_txnmgr.c:376 jfs_mkdir+0x226/0xb00 fs/jfs/namei.c:232 vfs_mkdir+0x402/0x620 fs/namei.c:5272 filename_mkdirat+0x289/0x520 fs/namei.c:5305 __do_sys_mkdir fs/namei.c:5332 [inline] __se_sys_mkdir+0x34/0x150 fs/namei.c:5329 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f48a452ce59 RSP: 002b:00007f48a2765028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007f48a47a6090 RCX: 00007f48a452ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000000 RBP: 00007f48a45c2e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f48a47a6128 R14: 00007f48a47a6090 R15: 00007ffc97696878 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8dfc2fc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8dfc2fc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8dfc2fc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 5 locks held by kworker/u8:5/67: 3 locks held by kworker/u8:9/1251: #0: ffff888031951138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff888031951138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90005da7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90005da7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x123/0x16e0 net/ipv6/addrconf.c:4223 2 locks held by getty/5354: #0: ffff888028c860a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cd32e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/7650: 7 locks held by kworker/u8:2/7963: 2 locks held by syz.7.297/8290: #0: ffff88803e830500 (sb_writers#19){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff888062dd6648 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff888062dd6648 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff888062dd6648 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff888062dd6648 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4951 1 lock held by syz-executor/9221: #0: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x65e/0xdf0 net/ipv6/addrconf.c:5056 1 lock held by syz-executor/9315: #0: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x464/0x19e0 net/ipv4/devinet.c:978 3 locks held by syz.8.411/9483: #0: ffff8880606c6128 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1259 #1: ffff88803a9fa500 (sb_writers#9){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2728 [inline] #1: ffff88803a9fa500 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683 #2: ffff888033947c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336 2 locks held by syz-executor/9647: #0: ffffffff8ebacf88 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8ebacf88 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8ebacf88 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4150 1 lock held by syz-executor/9687: #0: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f36f7f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4150 6 locks held by dhcpcd-run-hook/9880: ============================================= 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 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65 trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: 7963 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: netns cleanup_net RIP: 0010:__bfs_next kernel/locking/lockdep.c:1702 [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+0x1745/0x2ce0 kernel/locking/lockdep.c:5237 Code: 48 89 05 ae e9 d7 13 31 ff 45 31 ff 4d 85 ff 4c 8b 6c 24 08 74 2e 49 8b 47 30 48 85 c0 74 25 48 8b 40 10 48 83 c0 30 49 8b 0f <48> 89 8c 24 d8 00 00 00 48 39 c1 74 0d 4c 8b bc 24 d8 00 00 00 4d RSP: 0018:ffffc90003e7e890 EFLAGS: 00000086 RAX: ffffffff931a4e48 RBX: 00000000000003cd RCX: ffffffff96287df8 RDX: ffffffff961de968 RSI: ffff88802a2b2c20 RDI: 00000000000003cd RBP: e4e70c7552788f70 R08: ffffc90003e7e858 R09: 0000000000000020 R10: 0000000000000000 R11: ffffffff81a10390 R12: 0000000000000115 R13: ffff88802a2b2c20 R14: ffff88802a2b1f00 R15: ffffffff96277e08 FS: 0000000000000000(0000) GS:ffff88812621a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1f75881000 CR3: 0000000032ff6000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 _raw_spin_lock_nested+0x32/0x50 kernel/locking/spinlock.c:382 raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667 raw_spin_rq_lock kernel/sched/sched.h:1653 [inline] _task_rq_lock+0xc0/0x440 kernel/sched/core.c:762 __set_cpus_allowed_ptr kernel/sched/core.c:3202 [inline] ___migrate_enable+0xbb/0x1f0 kernel/sched/core.c:2476 __migrate_enable include/linux/sched.h:2456 [inline] migrate_enable include/linux/sched.h:2505 [inline] idr_preload_end include/linux/idr.h:191 [inline] __kernfs_new_node+0x89e/0xa70 fs/kernfs/dir.c:677 kernfs_new_node+0xea/0x140 fs/kernfs/dir.c:751 __kernfs_create_file+0x4b/0x2e0 fs/kernfs/file.c:1050 sysfs_add_file_mode_ns+0x237/0x300 fs/sysfs/file.c:316 create_files fs/sysfs/group.c:82 [inline] internal_create_group+0x679/0x1180 fs/sysfs/group.c:189 internal_create_groups fs/sysfs/group.c:229 [inline] sysfs_create_groups+0x59/0x120 fs/sysfs/group.c:255 device_add_groups drivers/base/core.c:2907 [inline] device_add_attrs+0xde/0x600 drivers/base/core.c:2971 device_add+0x488/0xb80 drivers/base/core.c:3711 netdev_register_kobject+0x178/0x310 net/core/net-sysfs.c:2337 register_netdevice+0x1455/0x1ed0 net/core/dev.c:11439 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1070 [inline] nsim_create+0xbe9/0x1150 drivers/net/netdevsim/netdev.c:1152 __nsim_dev_port_add+0x7f8/0xcd0 drivers/net/netdevsim/dev.c:1509 nsim_dev_port_add_all+0x37/0xf0 drivers/net/netdevsim/dev.c:1570 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1622 [inline] nsim_dev_reload_up+0x4dd/0x880 drivers/net/netdevsim/dev.c:1058 devlink_reload+0x4bb/0x890 net/devlink/dev.c:475 devlink_pernet_pre_exit+0x1ff/0x420 net/devlink/core.c:560 ops_pre_exit_list net/core/net_namespace.c:161 [inline] ops_undo_list+0x17d/0x8d0 net/core/net_namespace.c:234 cleanup_net+0x575/0x810 net/core/net_namespace.c:702 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245