INFO: task syz-executor:5833 blocked for more than 143 seconds. Not tainted 6.16.0-rc2-syzkaller-00047-g52da431bf03b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:18024 pid:5833 tgid:5833 ppid:1 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 __bch2_fs_stop+0x704/0x900 fs/bcachefs/super.c:697 generic_shutdown_super+0x135/0x2c0 fs/super.c:643 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2618 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa925b8fc57 RSP: 002b:00007ffdafa18f68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fa925b8fc57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdafa19020 RBP: 00007ffdafa19020 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdafa1a0b0 R13: 00007fa925c10925 R14: 000000000005eb4e R15: 00007ffdafa1a0f0 Showing all locks held in the system: 7 locks held by kworker/0:0/9: #0: ffff88801a479548 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a479548 ((wq_completion)events_long){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc900000e7bc0 (serio_event_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900000e7bc0 (serio_event_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8ef8e428 (serio_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:225 [inline] #2: ffffffff8ef8e428 (serio_mutex){+.+.}-{4:4}, at: serio_handle_event+0x25/0x860 drivers/input/serio/serio.c:189 #3: ffff88804032c2e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #3: ffff88804032c2e8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004 #4: ffff88804032c1d8 (&serio->drv_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:225 [inline] #4: ffff88804032c1d8 (&serio->drv_mutex){+.+.}-{4:4}, at: serio_connect_driver drivers/input/serio/serio.c:41 [inline] #4: ffff88804032c1d8 (&serio->drv_mutex){+.+.}-{4:4}, at: serio_driver_probe+0x58/0xa0 drivers/input/serio/serio.c:747 #5: ffffffff8ef9dcc8 (psmouse_mutex){+.+.}-{4:4}, at: psmouse_connect+0x9a/0x14a0 drivers/input/mouse/psmouse-base.c:1583 #6: ffff888076d28880 (&ps2dev->cmd_mutex){+.+.}-{4:4}, at: ps2_begin_command drivers/input/serio/libps2.c:131 [inline] #6: ffff888076d28880 (&ps2dev->cmd_mutex){+.+.}-{4:4}, at: ps2_command+0x70/0xe0 drivers/input/serio/libps2.c:407 5 locks held by kworker/u8:1/13: 1 lock held by khungtaskd/31: #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 5 locks held by kworker/u8:4/65: #0: ffff88801b2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc9000210fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000210fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8f5036d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:662 #3: ffffffff8f5102c8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12630 #4: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #4: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998 2 locks held by getty/5593: #0: ffff888030ac50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000362c2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5833: #0: ffff88805ea040e0 (&type->s_umount_key#95){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88805ea040e0 (&type->s_umount_key#95){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88805ea040e0 (&type->s_umount_key#95){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 3 locks held by syz-executor/5841: 1 lock held by napi/wg1-0/5928: #0: ffff8880b873b918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606 2 locks held by kworker/u8:8/5956: 3 locks held by kworker/u8:19/7967: #0: ffff88801a481148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a481148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc9000459fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000459fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8f5102c8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 1 lock held by syz.9.1827/11591: #0: ffff88804c6e60e0 (&type->s_umount_key#50){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88804c6e60e0 (&type->s_umount_key#50){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz-executor/12575: #0: ffffffff8f5102c8 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x37a/0x1df0 drivers/net/tun.c:3038 1 lock held by syz.5.2157/12577: #0: ffffffff8ef8e428 (serio_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:225 [inline] #0: ffffffff8ef8e428 (serio_mutex){+.+.}-{4:4}, at: serio_unregister_port+0x2f/0x150 drivers/input/serio/serio.c:676 2 locks held by syz.7.2172/12622: #0: ffff88807711b808 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff88807711b808 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline] #0: ffff88807711b808 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1391 #1: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #1: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998 1 lock held by syz.7.2172/12623: #0: ffffffff8f5102c8 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x37a/0x1df0 drivers/net/tun.c:3038 1 lock held by syz.7.2172/12628: #0: ffffffff8f5102c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f5102c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f5102c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink+0x331/0x710 net/core/rtnetlink.c:3545 1 lock held by syz.0.2173/12627: #0: ffffffff8f5102c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f5102c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6950 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-syzkaller-00047-g52da431bf03b #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5841 Comm: syz-executor Not tainted 6.16.0-rc2-syzkaller-00047-g52da431bf03b #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:118 [inline] RIP: 0010:lock_acquire+0x94/0x360 kernel/locking/lockdep.c:5847 Code: 0f 84 d7 01 00 00 83 3d 49 0d 03 0e 00 0f 84 f0 00 00 00 48 8b b4 24 90 00 00 00 4c 89 ef e8 33 7e 85 00 83 3d 2c 0d 03 0e 00 <0f> 84 fa 00 00 00 65 8b 05 2f fe fe 10 85 c0 0f 85 eb 00 00 00 65 RSP: 0018:ffffc9000395f820 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0545187d97252100 RDX: 0000000000000000 RSI: ffffffff8b680816 RDI: 1ffff1100484309c RBP: ffffffff8404ea2b R08: 0000000000000001 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed100484320d R12: 0000000000000000 R13: ffff8880242184e0 R14: 0000000000000000 R15: 0000000000000001 FS: 000055556aabc500(0000) GS:ffff888125d51000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f742d781178 CR3: 00000000292e1000 CR4: 0000000000350ef0 Call Trace: down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577 f2fs_down_write fs/f2fs/f2fs.h:2229 [inline] block_operations fs/f2fs/checkpoint.c:1258 [inline] f2fs_write_checkpoint+0x97b/0x1de0 fs/f2fs/checkpoint.c:1638 kill_f2fs_super+0x2c3/0x6c0 fs/f2fs/super.c:5076 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9007b8fc57 Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffe8142baf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f9007c10925 RCX: 00007f9007b8fc57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe8142bbb0 RBP: 00007ffe8142bbb0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe8142cc40 R13: 00007f9007c10925 R14: 000000000001a162 R15: 00007ffe8142cc80