INFO: task syz-executor.0:11211 blocked for more than 143 seconds. Not tainted 6.6.0-rc4-syzkaller-01097-g19537e125cc7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8cbab360 (rcu_read_lock ){....}-{1:2} , at: rcu_lock_acquire include/linux/rcupdate.h:303 [inline] , at: rcu_read_lock include/linux/rcupdate.h:749 [inline] , at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6613 2 locks held by getty/4795: #0: ffff888025f510a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc5/0x1480 drivers/tty/n_tty.c:2206 2 locks held by syz-fuzzer/5070: 2 locks held by kworker/0:0/31736: #0: ffff888012c72938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc90016c47d80 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 4 locks held by syz-executor.4/11248: #0: ffff8880777c90b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:552 #1: ffff8880777c8078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x345/0x1160 net/bluetooth/hci_sync.c:5008 #2: ffffffff8e85fce8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1947 [inline] #2: ffffffff8e85fce8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xc4/0x260 net/bluetooth/hci_conn.c:2558 #3: ffffffff8cbb6c38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #3: ffffffff8cbb6c38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x404/0x7e0 kernel/rcu/tree_exp.h:992 2 locks held by kworker/u4:40/11282: 1 lock held by syz-executor.2/11300: #0: ffffffff8cbb6c38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #0: ffffffff8cbb6c38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x404/0x7e0 kernel/rcu/tree_exp.h:992 1 lock held by dhcpcd/11356: #0: ffff8880ad0e5c10 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #0: ffff8880ad0e5c10 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release+0x86/0x260 net/socket.c:658 1 lock held by dhcpcd/11357: #0: ffff8880ad0e6e10 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #0: ffff8880ad0e6e10 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release+0x86/0x260 net/socket.c:658 1 lock held by dhcpcd/11358: #0: ffff8880ad0e3810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #0: ffff8880ad0e3810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release+0x86/0x260 net/socket.c:658 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.6.0-rc4-syzkaller-01097-g19537e125cc7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x299/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf87/0x1210 kernel/hung_task.c:379 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5070 Comm: syz-fuzzer Not tainted 6.6.0-rc4-syzkaller-01097-g19537e125cc7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 RIP: 0033:0x41f5b0 Code: 81 fe 00 00 40 00 0f 83 38 02 00 00 48 8b 14 f2 48 89 c6 48 c1 e8 0d 25 ff 1f 00 00 48 8b bc c2 00 40 10 00 84 02 48 8b 57 68 <48> 85 d2 0f 84 00 02 00 00 44 0f b6 47 62 66 90 41 f6 c0 01 0f 85 RSP: 002b:000000c000aa9e88 EFLAGS: 00000246 RAX: 0000000000000799 RBX: 000000c000045238 RCX: 000000c000f328a0 RDX: 0000000000000030 RSI: 000000c000f328a0 RDI: 00007f886a593b40 RBP: 000000c000aa9f08 R08: 0000000000011838 R09: 000000c002707000 R10: 000000000000008f R11: 000000000000008e R12: 000000c000aa9f08 R13: 0000000000000001 R14: 000000c0027a49c0 R15: 000000000113d000 FS: 000000c00ef6c890 GS: 0000000000000000