INFO: task syz-executor:5830 blocked for more than 143 seconds. Not tainted 6.15.0-rc1-next-20250411-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:19576 pid:5830 tgid:5830 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b9a/0x5250 kernel/sched/core.c:6769 __schedule_loop kernel/sched/core.c:6847 [inline] schedule+0x163/0x360 kernel/sched/core.c:6862 netfs_wait_for_outstanding_io include/linux/netfs.h:558 [inline] v9fs_evict_inode+0x17e/0x370 fs/9p/vfs_inode.c:348 evict+0x4f9/0x9b0 fs/inode.c:810 __dentry_kill+0x20d/0x630 fs/dcache.c:660 dput+0x19f/0x2b0 fs/dcache.c:902 shrink_dcache_for_umount+0xb4/0x180 fs/dcache.c:1612 generic_shutdown_super+0x6a/0x2d0 fs/super.c:621 kill_anon_super+0x3b/0x70 fs/super.c:1287 v9fs_kill_super+0x4c/0x90 fs/9p/vfs_super.c:193 deactivate_locked_super+0xc4/0x130 fs/super.c:474 cleanup_mnt+0x422/0x4c0 fs/namespace.c:1435 task_work_run+0x251/0x310 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc4b8b8f497 RSP: 002b:00007ffde3b3f848 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fc4b8c10854 RCX: 00007fc4b8b8f497 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffde3b3f900 RBP: 00007ffde3b3f900 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffde3b40990 R13: 00007fc4b8c10854 R14: 0000000000075148 R15: 00007ffde3b409d0 Showing all locks held in the system: 2 locks held by kworker/0:0/9: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc900000e7c60 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900000e7c60 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 1 lock held by khungtaskd/31: #0: ffffffff8ed3f180 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3f180 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3f180 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5585: #0: ffff888031fd30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5830: #0: ffff88803282e0e0 (&type->s_umount_key#57){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88803282e0e0 (&type->s_umount_key#57){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88803282e0e0 (&type->s_umount_key#57){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:506 3 locks held by syz-executor/5832: #0: ffff888034304d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff888034304d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2678 #1: ffff888034304078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x60f/0x1260 net/bluetooth/hci_sync.c:5213 #2: ffffffff8ed446b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #2: ffffffff8ed446b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998 3 locks held by kworker/0:5/5883: #0: ffff8880b8639f18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb0/0x140 kernel/sched/core.c:613 #1: ffff8880b8623f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x41f/0x7a0 kernel/sched/psi.c:987 #2: ffff8880b8625958 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1046 [inline] #2: ffff8880b8625958 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x24c/0x10f0 kernel/time/timer.c:1127 2 locks held by kworker/u8:15/6371: #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc9001ae0fc60 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9001ae0fc60 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 1 lock held by syz.5.892/9439: #0: ffffffff90103248 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline] #0: ffffffff90103248 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3390 4 locks held by syz.4.900/9448: #0: ffff888034ba4d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff888034ba4d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2678 #1: ffff888034ba4078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x60f/0x1260 net/bluetooth/hci_sync.c:5213 #2: ffffffff90269568 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2066 [inline] #2: ffffffff90269568 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2701 #3: ffff888027dcdb38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x71/0x690 net/bluetooth/l2cap_core.c:1761 1 lock held by syz.2.905/9472: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc1-next-20250411-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 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+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 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: 0 Comm: swapper/1 Not tainted 6.15.0-rc1-next-20250411-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:81 Code: cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d b3 02 15 00 f3 0f 1e fa fb f4 cc cc cc cc 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197dc0 EFLAGS: 000002c2 RAX: e2ad4ecc41511300 RBX: ffffffff8197d17e RCX: ffffffff8c333afc RDX: 0000000000000001 RSI: ffffffff8e6ab01c RDI: ffffffff8ca1ee40 RBP: ffffc90000197f20 R08: ffff8880b8732f5b R09: 1ffff110170e65eb R10: dffffc0000000000 R11: ffffed10170e65ec R12: 1ffff92000032fd2 R13: 1ffff11003ad9b40 R14: 0000000000000001 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888125080000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000387030 CR3: 0000000034678000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:748 default_idle_call+0x74/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x22e/0x5d0 kernel/sched/idle.c:325 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:423 start_secondary+0xfe/0x100 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x147