INFO: task kworker/u8:31:6876 blocked for more than 143 seconds. Not tainted 6.14.0-rc2-syzkaller-00185-g128c8f96eb86 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:31 state:D stack:24560 pid:6876 tgid:6876 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_timeout+0x244/0x280 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116 __debugfs_file_removed fs/debugfs/inode.c:775 [inline] remove_one+0x30f/0x420 fs/debugfs/inode.c:782 simple_recursive_removal+0x4e2/0x8e0 fs/libfs.c:635 debugfs_remove+0x5d/0x80 fs/debugfs/inode.c:805 nsim_dev_health_exit+0x3b/0xe0 drivers/net/netdevsim/health.c:227 nsim_dev_reload_destroy+0x143/0x4d0 drivers/net/netdevsim/dev.c:1664 nsim_dev_reload_down+0x6e/0xd0 drivers/net/netdevsim/dev.c:968 devlink_reload+0x19a/0x7c0 net/devlink/dev.c:461 devlink_pernet_pre_exit+0x1a1/0x2b0 net/devlink/core.c:509 ops_pre_exit_list net/core/net_namespace.c:162 [inline] cleanup_net+0x497/0xbf0 net/core/net_namespace.c:632 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz.5.456:8082 blocked for more than 145 seconds. Not tainted 6.14.0-rc2-syzkaller-00185-g128c8f96eb86 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.456 state:D stack:26824 pid:8082 tgid:8076 ppid:7772 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730 devlink_health_report+0x3c5/0x9d0 net/devlink/health.c:627 nsim_dev_health_break_write+0x167/0x210 drivers/net/netdevsim/health.c:162 full_proxy_write+0x13c/0x200 fs/debugfs/file.c:398 vfs_write+0x24c/0x1150 fs/read_write.c:677 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcfc2d8cde9 RSP: 002b:00007fcfc3b65038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fcfc2fa6160 RCX: 00007fcfc2d8cde9 RDX: 00000000000000ef RSI: 0000400000000000 RDI: 0000000000000007 RBP: 00007fcfc2e0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fcfc2fa6160 R15: 00007ffd027c6da8 Showing all locks held in the system: 3 locks held by kworker/u8:1/12: #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90000117d18 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffffffff8fef7d68 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:285 1 lock held by khungtaskd/30: #0: ffffffff8e1bcc80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bcc80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bcc80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 2 locks held by getty/6373: #0: ffff888035ed20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000bebb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 6 locks held by kworker/u8:31/6876: #0: ffff88801bef5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90004a4fd18 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffffffff8fee2090 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xca/0xbf0 net/core/net_namespace.c:606 #3: ffff888064a610e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #3: ffff888064a610e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff888064a610e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x12d/0x2b0 net/devlink/core.c:506 #4: ffff888064973250 (&devlink->lock_key){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff888064973250 (&devlink->lock_key){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff888064973250 (&devlink->lock_key){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x137/0x2b0 net/devlink/core.c:506 #5: ffff88807c28ef20 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline] #5: ffff88807c28ef20 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: simple_recursive_removal+0x2f5/0x8e0 fs/libfs.c:627 3 locks held by syz.5.456/8082: #0: ffff888028025278 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x267/0x390 fs/file.c:1192 #1: ffff88801ead4420 (sb_writers#9){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:731 #2: ffff888064973250 (&devlink->lock_key){+.+.}-{4:4}, at: devlink_health_report+0x3c5/0x9d0 net/devlink/health.c:627 2 locks held by syz.2.599/8831: #0: ffff88801ead4420 (sb_writers#9){.+.+}-{0:0}, at: open_last_lookups fs/namei.c:3739 [inline] #0: ffff88801ead4420 (sb_writers#9){.+.+}-{0:0}, at: path_openat+0x1f64/0x2d80 fs/namei.c:3986 #1: ffff88807c28ef20 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:887 [inline] #1: ffff88807c28ef20 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: open_last_lookups fs/namei.c:3749 [inline] #1: ffff88807c28ef20 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: path_openat+0x88a/0x2d80 fs/namei.c:3986 2 locks held by syz.7.984/10601: #0: ffffffff8fef7d68 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fef7d68 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3517 #1: ffffffff8e1c80f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:302 2 locks held by syz.6.1015/10754: 2 locks held by syz.6.1021/10778: #0: ffffffff8fee2090 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x292/0x6c0 net/core/net_namespace.c:512 #1: ffffffff8fef7d68 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x1b/0x70 net/ipv4/nexthop.c:3878 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc2-syzkaller-00185-g128c8f96eb86 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244