INFO: task syz-executor:7331 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-02443-g015a99fa7665 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:19840 pid:7331 tgid:7331 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0x165/0x360 kernel/sched/core.c:6874 __bch2_fs_stop+0x704/0x900 fs/bcachefs/super.c:709 generic_shutdown_super+0x135/0x2c0 fs/super.c:643 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2600 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1432 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: 0033:0x7f9b1e18fc97 RSP: 002b:00007fff17b13e08 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f9b1e18fc97 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff17b13ec0 RBP: 00007fff17b13ec0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff17b14f50 R13: 00007f9b1e21089d R14: 000000000003b38f R15: 00007fff17b14f90 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13cb40 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13cb40 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13cb40 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by getty/5583: #0: ffff88814d2580a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fee2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5822: #0: ffffffff8e142678 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8e142678 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 1 lock held by udevd/5891: 1 lock held by syz-executor/7331: #0: ffff88802850e0e0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88802850e0e0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88802850e0e0 (&type->s_umount_key#62){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 1 lock held by syz.4.1009/9647: #0: ffff88802850e0e0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88802850e0e0 (&type->s_umount_key#62){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 3 locks held by syz-executor/9783: #0: ffffffff8f503788 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f503788 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f503788 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4064 #1: ffff88807a21cd30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2751 [inline] #1: ffff88807a21cd30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] #1: ffff88807a21cd30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: do_setlink+0x370/0x40d0 net/core/rtnetlink.c:3051 #2: ffffffff8e142678 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #2: ffffffff8e142678 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-02443-g015a99fa7665 #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:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 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: 43 Comm: kworker/1:1 Not tainted 6.15.0-syzkaller-02443-g015a99fa7665 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:format_decode+0x644/0xe30 lib/vsprintf.c:2705 Code: 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 55 05 00 00 41 08 2f 49 ff c4 49 81 e6 00 00 ff ff 49 09 de 4c 0b 74 24 10 4c 89 e0 <4c> 89 f2 48 83 c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d e9 f1 16 b6 f5 RSP: 0018:ffffc90000b36ad0 EFLAGS: 00000246 RAX: ffffffff8b8b7a81 RBX: 0000000000000025 RCX: 0000000000100000 RDX: ffffc9001c73c000 RSI: 00000000000287d7 RDI: 00000000000287d8 RBP: ffffffff8b8b7a80 R08: ffff888020edbc00 R09: 0000000000000002 R10: 0000000000000025 R11: 0000000000000002 R12: ffffffff8b8b7a81 R13: ffffc90000b36b78 R14: 0000000000000000 R15: ffffffff8b8b7a80 FS: 0000000000000000(0000) GS:ffff888125d91000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c687544168 CR3: 000000007ad02000 CR4: 0000000000350ef0 Call Trace: vsnprintf+0x102/0xf00 lib/vsprintf.c:2795 sprintf+0xd9/0x120 lib/vsprintf.c:3015 print_time kernel/printk/printk.c:1381 [inline] info_print_prefix+0x155/0x310 kernel/printk/printk.c:1407 record_print_text+0x154/0x430 kernel/printk/printk.c:1456 printk_get_next_message+0x26d/0x7b0 kernel/printk/printk.c:3024 console_emit_next_record kernel/printk/printk.c:3092 [inline] console_flush_all+0x4ca/0xc40 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xc4/0x270 kernel/printk/printk.c:3325 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450 dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4917 dev_printk_emit+0xe0/0x130 drivers/base/core.c:4928 _dev_info+0x10a/0x160 drivers/base/core.c:4986 usb_disconnect+0xdd/0x910 drivers/usb/core/hub.c:2298 hub_port_connect drivers/usb/core/hub.c:5371 [inline] hub_port_connect_change drivers/usb/core/hub.c:5671 [inline] port_event drivers/usb/core/hub.c:5831 [inline] hub_event+0x1cdb/0x4a00 drivers/usb/core/hub.c:5913 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 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