INFO: task syz.1.502:9884 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.1.502 state:D stack:27496 pid:9884 tgid:9882 ppid:5585 task_flags:0x400040 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 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:5276 filename_mkdirat+0x289/0x520 fs/namei.c:5309 __do_sys_mkdirat fs/namei.c:5330 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5327 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: 0033:0x7f35475fcf47 RSP: 002b:00007f3545834e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f3545834ee0 RCX: 00007f35475fcf47 RDX: 00000000000001ff RSI: 0000200000000340 RDI: 00000000ffffff9c RBP: 0000200000000080 R08: 0000200000000140 R09: 0000000000000000 R10: 0000200000000080 R11: 0000000000000246 R12: 0000200000000340 R13: 00007f3545834ea0 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/43: 5 locks held by kworker/u8:3/56: 3 locks held by kworker/u8:5/69: #0: ffff888031bf2938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff888031bf2938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc9000154fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000154fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x123/0x16e0 net/ipv6/addrconf.c:4229 6 locks held by kworker/u8:6/110: 6 locks held by kworker/u8:12/1218: 9 locks held by kworker/u8:13/1580: 2 locks held by getty/5341: #0: ffff888028b580a0 (&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 2 locks held by kworker/0:7/5856: 3 locks held by kworker/0:8/5858: #0: ffff88813ff1b938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88813ff1b938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc9000595fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000595fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffff88803c043280 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490 2 locks held by syz.1.502/9884: #0: ffff88802a3ca500 (sb_writers#26){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff888067cac950 (&type->i_mutex_dir_key#20/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline] #1: ffff888067cac950 (&type->i_mutex_dir_key#20/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline] #1: ffff888067cac950 (&type->i_mutex_dir_key#20/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline] #1: ffff888067cac950 (&type->i_mutex_dir_key#20/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4955 1 lock held by syz-executor/10744: #0: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x464/0x19e0 net/ipv4/devinet.c:978 5 locks held by syz-executor/11024: 4 locks held by syz-executor/11254: #0: ffff888035902500 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff888035902500 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683 #1: ffff888060102478 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336 #2: ffff8880297194b8 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff8880297194b8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337 #3: ffffffff8ee21098 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x13c/0x710 drivers/net/netdevsim/bus.c:184 10 locks held by syz-executor/11266: 4 locks held by syz-executor/11267: #0: ffff888035902500 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline] #0: ffff888035902500 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683 #1: ffff8880261d5078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336 #2: ffff8880297193c8 (kn->active#51){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline] #2: ffff8880297193c8 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337 #3: ffffffff8ee21098 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 3 locks held by kworker/1:4/11373: #0: ffff88813ff1b938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88813ff1b938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc9000158fc40 (netdev_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000158fc40 (netdev_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff8f5ac438 (rtnl_mutex){+.+.}-{4:4}, at: netdev_work_proc+0x72/0x7f0 net/core/netdev_work.c:132 7 locks held by dhcpcd-run-hook/11422: ============================================= 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 07/24/2026 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: 11024 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:usage_skip kernel/locking/lockdep.c:2253 [inline] RIP: 0010:__bfs kernel/locking/lockdep.c:1800 [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+0x17f8/0x2ce0 kernel/locking/lockdep.c:5237 Code: 89 ca 80 e2 fa 80 78 2b 00 0f b6 c2 0f 44 c1 84 c0 0f 84 42 ff ff ff a8 0c 41 0f 94 47 2b 4d 8b 6f 10 41 0f b6 85 c6 00 00 00 <85> c0 74 5e 83 f8 01 0f 85 22 ff ff ff 83 3d 54 80 07 18 00 0f 85 RSP: 0018:ffffc9000541dda0 EFLAGS: 00000002 RAX: 0000000000000000 RBX: 00000000000003cd RCX: 0000000000000008 RDX: 0000000000000008 RSI: ffff88802ffa69d0 RDI: 00000000000003cd RBP: dec2d6ac47ae3a93 R08: ffffc9000541dd68 R09: 0000000000000020 R10: 0000000000000000 R11: ffffffff81a1c7e0 R12: 000000000000054d R13: ffffffff9347b0d8 R14: ffff88802ffa5d00 R15: ffffffff962a8728 FS: 000055556c4e6500(0000) GS:ffff888125c45000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc2e08aeb30 CR3: 0000000041e1a000 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_irq+0x4d/0xa0 kernel/sched/core.c:7556 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872 Code: ff ff ff e8 61 3a a2 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 cb 54 fc 10 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 18 51 11 RSP: 0018:ffffc9000541e360 EFLAGS: 00000286 RAX: 4527414ef5104900 RBX: 0000000000000000 RCX: 0000000000000046 RDX: 000000006d3ef621 RSI: ffffffff8daf111c RDI: ffffffff8bca5980 RBP: ffffffff84ff1ebc R08: ffffffff84ff1ebc R09: 0000000000000000 R10: 0000000000000000 R11: ffff888035e88818 R12: 0000000000000000 R13: ffff888035e88818 R14: 0000000000000001 R15: 0000000000000246 rt_spin_lock+0x83/0x400 kernel/locking/spinlock_rt.c:56 spin_lock include/linux/spinlock_rt.h:45 [inline] ref_tracker_alloc+0x1ec/0x4c0 lib/ref_tracker.c:279 __netdev_tracker_alloc include/linux/netdevice.h:4496 [inline] netdev_hold include/linux/netdevice.h:4525 [inline] fib_check_nh_nongw net/ipv4/fib_semantics.c:1290 [inline] fib_check_nh+0xcf1/0x1ac0 net/ipv4/fib_semantics.c:1310 fib_create_info+0x200e/0x3170 net/ipv4/fib_semantics.c:1530 fib_table_insert+0xcb/0x1b10 net/ipv4/fib_trie.c:1212 fib_magic+0x43b/0x530 net/ipv4/fib_frontend.c:1128 fib_add_ifaddr+0x376/0x5d0 net/ipv4/fib_frontend.c:1165 fib_netdev_event+0x382/0x490 net/ipv4/fib_frontend.c:1510 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2288 [inline] call_netdevice_notifiers net/core/dev.c:2302 [inline] __dev_notify_flags+0x1aa/0x310 net/core/dev.c:9803 netif_change_flags+0xde/0x1b0 net/core/dev.c:9832 do_setlink+0xdd6/0x4670 net/core/rtnetlink.c:3215 rtnl_changelink net/core/rtnetlink.c:3849 [inline] __rtnl_newlink net/core/rtnetlink.c:4022 [inline] rtnl_newlink+0x15c2/0x1bd0 net/core/rtnetlink.c:4159 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7076 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7f5/0x990 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775 __sock_sendmsg net/socket.c:790 [inline] __sys_sendto+0x41e/0x5d0 net/socket.c:2252 __do_sys_sendto net/socket.c:2259 [inline] __se_sys_sendto net/socket.c:2255 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2255 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: 0033:0x7f5ad1eee90e 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:00007fff9e915058 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055556c4e6500 RCX: 00007f5ad1eee90e RDX: 000000000000002c RSI: 00007f5ad2ce4670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007fff9e9150d4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f5ad2ce4670 R15: 0000000000000000