INFO: task syz.1.305:9944 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.305 state:D stack:25672 pid:9944 tgid:9938 ppid:9539 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] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7607 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1670 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline] __rt_mutex_slowlock_locked+0x1f84/0x25b0 kernel/locking/rtmutex.c:1787 __rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114 rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline] __down_read kernel/locking/rwsem.c:1502 [inline] down_read+0x132/0x200 kernel/locking/rwsem.c:1576 __super_lock fs/super.c:60 [inline] super_lock+0x2d6/0x3d0 fs/super.c:122 __iterate_supers+0x120/0x240 fs/super.c:866 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl+0x3a0/0x9a0 fs/quota/quota.c:917 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: 0033:0x7f4f8be1de59 RSP: 002b:00007f4f8a055028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007f4f8c0a6090 RCX: 00007f4f8be1de59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102 RBP: 00007f4f8beb3e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4f8c0a6128 R14: 00007f4f8c0a6090 R15: 00007fffba95ed88 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 6 locks held by kworker/u8:5/68: 3 locks held by kworker/u8:6/107: #0: ffff888032246138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff888032246138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc9000155fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc9000155fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff8f5b0ab8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f5b0ab8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x123/0x16e0 net/ipv6/addrconf.c:4229 11 locks held by kworker/u8:13/3347: 2 locks held by getty/5347: #0: ffff88803622b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:4/5721: #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: ffffc90005087c40 (netdev_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90005087c40 (netdev_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff8f5b0ab8 (rtnl_mutex){+.+.}-{4:4}, at: netdev_work_proc+0x72/0x7f0 net/core/netdev_work.c:116 2 locks held by syz-executor/7454: 1 lock held by syz.1.305/9944: #0: ffff88806428a0d0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88806428a0d0 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz-executor/10900: #0: ffffffff8f5b0ab8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f5b0ab8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x464/0x19e0 net/ipv4/devinet.c:978 3 locks held by syz-executor/10961: #0: ffffffff8f621be0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8f6219f8 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline] #1: ffffffff8f6219f8 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline] #1: ffffffff8f6219f8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208 #2: ffffffff8f5b0ab8 (rtnl_mutex){+.+.}-{4:4}, at: wg_set_device_doit+0x170/0x2120 drivers/net/wireguard/netlink.c:484 8 locks held by syz-executor/11017: 1 lock held by syz-executor/11096: #0: ffffffff8f5b0ab8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f5b0ab8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f5b0ab8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a3/0x1bd0 net/core/rtnetlink.c:4158 3 locks held by syz.4.439/11331: 1 lock held by dhcpcd-run-hook/11347: ============================================= 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: 3347 Comm: kworker/u8:13 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 kernel/locking/lockdep.c:1753 [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+0x17a5/0x2ce0 kernel/locking/lockdep.c:5237 Code: 00 00 0f 83 84 01 00 00 4e 8b 3c e5 a0 a9 a5 95 ff c0 25 ff 0f 00 00 89 05 48 47 05 14 4d 85 ff 0f 84 ac 01 00 00 49 8b 47 10 <48> 85 c0 0f 84 38 0d 00 00 8b 0d 34 47 05 14 39 48 5c 0f 84 6a ff RSP: 0018:ffffc9000fc3e440 EFLAGS: 00000082 RAX: ffffffff93477d58 RBX: 00000000000003cd RCX: ffffffff963a4e08 RDX: ffffffff9638e208 RSI: ffff888032bc6ac0 RDI: 00000000000003cd RBP: c28e6d84e60d9cf2 R08: ffffc9000fc3e408 R09: 0000000000000020 R10: 0000000000000000 R11: ffffffff81a13580 R12: 0000000000000681 R13: ffff888032bc6ac0 R14: ffff888032bc5d00 R15: ffffffff963a4e08 FS: 0000000000000000(0000) GS:ffff888125c49000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe81dc32286 CR3: 0000000060cde000 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:idr_get_free+0x147/0xa20 lib/radix-tree.c:-1 Code: 48 89 d8 48 c1 e8 03 49 bd 00 00 00 00 00 fc ff df 42 0f b6 04 28 84 c0 0f 85 5f 06 00 00 49 ff cf 0f b6 03 83 c0 06 89 04 24 <48> 89 eb 48 8b 44 24 58 42 0f b6 04 28 84 c0 0f 85 e4 05 00 00 49 RSP: 0018:ffffc9000fc3ea08 EFLAGS: 00000206 RAX: 0000000000000018 RBX: ffff88802a1d2100 RCX: 0000000000000012 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000058f99 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc9000fc3eb10 R11: fffff52001f87d64 R12: ffff88802a1d2102 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000ffffff idr_alloc_u32+0x190/0x340 lib/idr.c:48 idr_alloc_cyclic+0xa2/0x1c0 lib/idr.c:127 __kernfs_new_node+0x141/0xa70 fs/kernfs/dir.c:671 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:11440 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1070 [inline] nsim_create+0xbe9/0x1160 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