INFO: task syz.2.532:11163 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.2.532 state:D stack:27968 [ 753.023272][ T38] task:syz.2.532 state:D stack:27968 pid:11163 tgid:11145 ppid:10204 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x16d8/0x55e0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 io_schedule+0x7f/0xd0 kernel/sched/core.c:8110 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:5271 filename_mkdirat+0x289/0x520 fs/namei.c:5304 __do_sys_mkdir fs/namei.c:5331 [inline] __se_sys_mkdir+0x34/0x150 fs/namei.c:5328 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: 0033:0x7f9ca2f8ce59 RSP: 002b:00007f9ca11bd028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007f9ca3206090 RCX: 00007f9ca2f8ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000300 RBP: 00007f9ca3022d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9ca3206128 R14: 00007f9ca3206090 R15: 00007fff06333fd8 Showing all locks held in the system: 3 locks held by kworker/1:0/31: #0: ffff88813fe33938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #0: ffff88813fe33938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3397 #1: ffffc90000a5fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #1: ffffc90000a5fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3397 #2: ffff8880331e0280 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490 1 lock held by khungtaskd/38: #0: ffffffff8ddc7b60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8ddc7b60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8ddc7b60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 9 locks held by kworker/u8:3/56: 2 locks held by kworker/u8:6/152: 6 locks held by kworker/u8:13/3052: 1 lock held by udevd/4972: #0: ffff888037268480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 2 locks held by getty/5363: #0: ffff8880367e10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cb62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1390 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:4/5715: #0: ffff88813fe33938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #0: ffff88813fe33938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3397 #1: ffffc9000548fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #1: ffffc9000548fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3397 #2: ffff888064a18280 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490 2 locks held by syz.2.532/11163: #0: ffff88803e434480 (sb_writers#19){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff88806f160f60 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1074 [inline] #1: ffff88806f160f60 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2914 [inline] #1: ffff88806f160f60 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2938 [inline] #1: ffff88806f160f60 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4950 1 lock held by syz-executor/12248: 4 locks held by syz-executor/12414: #0: ffff888030d7c480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2724 [inline] #0: ffff888030d7c480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:684 #1: ffff888064b6f078 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:343 #2: ffff8880290dd2d8 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8880290dd2d8 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:344 #3: ffffffff8e9ce938 (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/12450: #0: ffff888030d7c480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2724 [inline] #0: ffff888030d7c480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:684 #1: ffff888061da2478 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:343 #2: ffff8880290dd2d8 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8880290dd2d8 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:344 #3: ffffffff8e9ce938 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x13c/0x710 drivers/net/netdevsim/bus.c:184 7 locks held by syz-executor/12475: #0: ffff888030d7c480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2724 [inline] #0: ffff888030d7c480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:684 #1: ffff88803827c878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:343 #2: ffff8880290dd1e8 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8880290dd1e8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:344 #3: ffffffff8e9ce938 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234 #4: ffff8880288cc160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline] #4: ffff8880288cc160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1174 [inline] #4: ffff8880288cc160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb9/0x880 drivers/base/dd.c:1372 #5: ffff888039dc6310 (&devlink->lock_key#30){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1799 #6: ffffffff8ddcdcf0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3828 3 locks held by dhcpcd-run-hook/12856: ============================================= 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:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 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: 3052 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:1815 [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+0x18fa/0x2cc0 kernel/locking/lockdep.c:5237 Code: 13 25 ff 0f 00 00 39 05 e0 b4 af 11 73 06 89 05 d8 b4 af 11 48 8b 02 48 89 df 4c 39 e8 0f 84 34 fe ff ff 4c 89 78 30 48 8b 00 <4c> 39 e8 75 f4 48 89 df e9 20 fe ff ff 48 89 fb 48 c7 c7 f0 4f c9 RSP: 0018:ffffc9000e0a6d68 EFLAGS: 00000006 RAX: ffffffff92f726f0 RBX: 00000000000003cd RCX: 000000000000055c RDX: ffffffff95e37688 RSI: ffff888031724a68 RDI: 00000000000003cd RBP: 76ef2b3bc14845f6 R08: ffffc9000e0a6d30 R09: 0000000000000020 R10: 0000000000000000 R11: ffffffff81a054b0 R12: 000000000000055b R13: ffffffff92f726f0 R14: ffff888031723d80 R15: ffffffff96098df8 FS: 0000000000000000(0000) GS:ffff8881263a1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055820ac20950 CR3: 0000000037ac8000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 debug_object_assert_init+0x70/0x340 lib/debugobjects.c:1062 debug_hrtimer_assert_init kernel/time/hrtimer.c:495 [inline] hrtimer_start_range_ns+0x3f/0xee0 kernel/time/hrtimer.c:1477 hrtimer_start include/linux/hrtimer.h:220 [inline] hrtick_cond_restart kernel/sched/core.c:924 [inline] hrtick_schedule_exit kernel/sched/core.c:986 [inline] finish_lock_switch kernel/sched/core.c:5124 [inline] finish_task_switch+0x3c7/0xbc0 kernel/sched/core.c:5243 context_switch kernel/sched/core.c:5391 [inline] __schedule+0x16e0/0x55e0 kernel/sched/core.c:7189 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8e0 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872 Code: ff ff ff e8 01 1d 77 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 db 07 a8 10 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 00 dd 7a 09 cc 48 8d 3d 38 0e cb RSP: 0018:ffffc9000e0a7408 EFLAGS: 00000282 RAX: 3bb98f65794ef100 RBX: 0000000000000000 RCX: 0000000000000046 RDX: ffffffff92fc9978 RSI: ffffffff8d65af62 RDI: ffffffff8b873ba0 RBP: ffffffff818d1145 R08: 0000000000000008 R09: ffffffff958cca98 R10: 00000000f98b4db3 R11: 00000000f975366c R12: 0000000000000000 R13: ffff888062a07538 R14: 0000000000000001 R15: 0000000000000246 touch_wq_lockdep_map+0xcb/0x180 kernel/workqueue.c:4029 __flush_workqueue+0x148/0x1470 kernel/workqueue.c:4071 drain_workqueue+0xce/0x380 kernel/workqueue.c:4235 destroy_workqueue+0xbb/0xc60 kernel/workqueue.c:6053 wg_destruct+0x1a0/0x310 drivers/net/wireguard/device.c:255 netdev_run_todo+0xc21/0xde0 net/core/dev.c:11723 default_device_exit_batch+0x966/0x9e0 net/core/dev.c:13077 ops_exit_list net/core/net_namespace.c:205 [inline] ops_undo_list+0x4b4/0x8d0 net/core/net_namespace.c:252 cleanup_net+0x575/0x810 net/core/net_namespace.c:702 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478 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