INFO: task syz.1.357:10309 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.1.357 state:D stack:25640 pid:10309 tgid:10308 ppid:8442 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x16dc/0x5500 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 io_schedule+0x80/0xe0 kernel/sched/core.c:8154 folio_wait_bit_common+0x83c/0xbc0 mm/filemap.c:1323 folio_lock include/linux/pagemap.h:1157 [inline] release_metapage+0x101/0xa50 fs/jfs/jfs_metapage.c:871 discard_metapage fs/jfs/jfs_metapage.h:88 [inline] __get_metapage+0x9ac/0xdf0 fs/jfs/jfs_metapage.c:754 dtSearch+0x56c/0x2010 fs/jfs/jfs_dtree.c:621 jfs_lookup+0x1b0/0x420 fs/jfs/namei.c:1464 lookup_one_qstr_excl+0x12d/0x360 fs/namei.c:1810 __start_dirop fs/namei.c:2920 [inline] start_dirop fs/namei.c:2942 [inline] filename_create+0x20e/0x370 fs/namei.c:4951 filename_mkdirat+0xd2/0x520 fs/namei.c:5298 __do_sys_mkdirat fs/namei.c:5326 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5323 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: 0033:0x7f42165cccc7 RSP: 002b:00007f4214825e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f4214825ee0 RCX: 00007f42165cccc7 RDX: 00000000000001ff RSI: 00002000000000c0 RDI: 00000000ffffff9c RBP: 0000200000000080 R08: 0000000000000000 R09: 0000000000000000 R10: 0000200000000080 R11: 0000000000000246 R12: 00002000000000c0 R13: 00007f4214825ea0 R14: 0000000000000000 R15: 0000200000002280 Showing all locks held in the system: 8 locks held by kworker/u8:0/12: 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 3 locks held by kworker/u8:4/66: #0: ffff88801b2ab138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88801b2ab138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc9000151fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000151fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffff88805ea620d0 (&type->s_umount_key#111){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:566 3 locks held by kworker/u8:14/1508: #0: ffff888032411938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff888032411938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90007007c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90007007c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff8f3716b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f3716b8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x123/0x16e0 net/ipv6/addrconf.c:4229 6 locks held by kworker/u8:19/3316: #0: ffff88801b2a8938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88801b2a8938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc9000f637c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000f637c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff8f362b20 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:673 #3: ffff88802fa36160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #3: ffff88802fa36160 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:124 [inline] #3: ffff88802fa36160 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x420 net/devlink/core.c:557 #4: ffff88803aec0310 (&devlink->lock_key#30){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:292 [inline] #4: ffff88803aec0310 (&devlink->lock_key#30){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:125 [inline] #4: ffff88803aec0310 (&devlink->lock_key#30){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x142/0x420 net/devlink/core.c:557 #5: ffffffff8f3716b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #5: ffffffff8f3716b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2163 2 locks held by getty/5358: #0: ffff888035a7e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211 1 lock held by syz.1.357/10309: #0: ffff888062df52f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #0: ffff888062df52f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #0: ffff888062df52f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #0: ffff888062df52f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4951 1 lock held by syz-executor/11311: 1 lock held by syz-executor/11335: #0: ffffffff8f3716b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f3716b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f3716b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4158 10 locks held by syz-executor/11351: 4 locks held by syz-executor/11371: #0: ffff8880118b6500 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2728 [inline] #0: ffff8880118b6500 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683 #1: ffff8880615c2478 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336 #2: ffff8880292db788 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff8880292db788 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337 #3: ffffffff8ebe7118 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x13c/0x710 drivers/net/netdevsim/bus.c:184 4 locks held by syz-executor/11478: #0: ffff8880118b6500 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2728 [inline] #0: ffff8880118b6500 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683 #1: ffff88805f6cac78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336 #2: ffff8880292db788 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff8880292db788 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337 #3: ffffffff8ebe7118 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x13c/0x710 drivers/net/netdevsim/bus.c:184 2 locks held by sed/11782: ============================================= 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 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11351 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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 9e 58 d8 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:ffffc9000440eae0 EFLAGS: 00000086 RAX: ffffffff931c6a60 RBX: 00000000000003cd RCX: ffffffff961cf8d8 RDX: ffffffff931c40f8 RSI: ffff88802f69cb98 RDI: 00000000000003cd RBP: d555748def8e0f05 R08: ffffc9000440eaa8 R09: 0000000000000020 R10: 0000000000000000 R11: ffffffff81a124a0 R12: 0000000000000044 R13: ffff88802f69cb98 R14: ffff88802f69be00 R15: ffffffff9609fdf8 FS: 000055558eb2e500(0000) GS:ffff888126111000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc9beecc000 CR3: 0000000060404000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 seqcount_lockdep_reader_access+0x55/0x100 include/linux/seqlock.h:73 ktime_get+0x45/0x220 kernel/time/timekeeping.c:971 hrtick_schedule_exit kernel/sched/core.c:1000 [inline] finish_lock_switch kernel/sched/core.c:5240 [inline] finish_task_switch+0x307/0xc60 kernel/sched/core.c:5359 context_switch kernel/sched/core.c:5513 [inline] __schedule+0x16e4/0x5500 kernel/sched/core.c:7234 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7413 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 class_preempt_destructor include/linux/preempt.h:468 [inline] raw_spin_unlock_irqrestore_wake include/linux/sched/wake_q.h:102 [inline] rtlock_slowlock kernel/locking/rtmutex.c:1923 [inline] rtlock_lock kernel/locking/spinlock_rt.c:43 [inline] __rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline] rt_spin_lock+0x316/0x400 kernel/locking/spinlock_rt.c:57 spin_lock include/linux/spinlock_rt.h:45 [inline] d_alloc+0x67/0x190 fs/dcache.c:1984 lookup_one_qstr_excl+0xd8/0x360 fs/namei.c:1806 __start_dirop fs/namei.c:2920 [inline] start_dirop+0x5c/0x90 fs/namei.c:2942 simple_start_creating+0xcc/0x110 fs/libfs.c:2305 debugfs_start_creating+0xdb/0x1a0 fs/debugfs/inode.c:394 __debugfs_create_file+0x6f/0x400 fs/debugfs/inode.c:428 debugfs_create_file_unsafe+0x3a/0x50 fs/debugfs/inode.c:509 nsim_bpf_init+0xee/0x270 drivers/net/netdevsim/bpf.c:626 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1063 [inline] nsim_create+0xba5/0x1150 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_drv_probe+0x8d6/0xc00 drivers/net/netdevsim/dev.c:1731 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x254/0xae0 drivers/base/dd.c:706 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1026 bus_for_each_drv+0x25b/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c7/0x450 drivers/base/dd.c:1098 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x12d/0x220 drivers/base/bus.c:620 device_add+0x7d7/0xb80 drivers/base/core.c:3772 nsim_bus_dev_new drivers/net/netdevsim/bus.c:471 [inline] new_device_store+0x37b/0x710 drivers/net/netdevsim/bus.c:191 kernfs_fop_write_iter+0x3a5/0x540 fs/kernfs/file.c:345 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61e/0xbb0 fs/read_write.c:687 ksys_write+0x156/0x270 fs/read_write.c:739 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: 0033:0x7f925aabe68e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007ffe5a93d138 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000055558eb2e500 RCX: 00007f925aabe68e RDX: 0000000000000003 RSI: 00007ffe5a93d1c0 RDI: 0000000000000005 RBP: 00007f925ab94716 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007ffe5a93d1c0 R14: 00007f925b8b4620 R15: 0000000000000003