Warning: Permanently added '10.128.1.180' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 29.679477] [ 29.681092] ============================================ [ 29.686513] WARNING: possible recursive locking detected [ 29.692111] 4.14.302-syzkaller #0 Not tainted [ 29.696576] -------------------------------------------- [ 29.702003] swapper/1/0 is trying to acquire lock: [ 29.706901] (&port_lock_key){-.-.}, at: [] uart_write+0x109/0x560 [ 29.714760] [ 29.714760] but task is already holding lock: [ 29.720696] (&port_lock_key){-.-.}, at: [] serial8250_handle_irq.part.0+0x20/0x390 [ 29.730033] [ 29.730033] other info that might help us debug this: [ 29.736666] Possible unsafe locking scenario: [ 29.736666] [ 29.742690] CPU0 [ 29.745240] ---- [ 29.747876] lock(&port_lock_key); [ 29.751471] lock(&port_lock_key); [ 29.755073] [ 29.755073] *** DEADLOCK *** [ 29.755073] [ 29.761102] May be due to missing lock nesting notation [ 29.761102] [ 29.768001] 3 locks held by swapper/1/0: [ 29.772116] #0: (&(&i->lock)->rlock){-.-.}, at: [] serial8250_interrupt+0x3a/0x210 [ 29.781641] #1: (&port_lock_key){-.-.}, at: [] serial8250_handle_irq.part.0+0x20/0x390 [ 29.791418] #2: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref+0x1b/0x80 [ 29.799891] [ 29.799891] stack backtrace: [ 29.804362] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.14.302-syzkaller #0 [ 29.811432] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 [ 29.820760] Call Trace: [ 29.823316] [ 29.825451] dump_stack+0x1b2/0x281 [ 29.829055] __lock_acquire.cold+0x180/0x97c [ 29.833462] ? __lock_acquire+0x2190/0x3f20 [ 29.837754] ? trace_hardirqs_on+0x10/0x10 [ 29.842571] ? trace_hardirqs_on+0x10/0x10 [ 29.846777] ? trace_hardirqs_on+0x10/0x10 [ 29.850993] lock_acquire+0x170/0x3f0 [ 29.854777] ? uart_write+0x109/0x560 [ 29.858556] _raw_spin_lock_irqsave+0x8c/0xc0 [ 29.863027] ? uart_write+0x109/0x560 [ 29.866801] uart_write+0x109/0x560 [ 29.870404] ? n_hdlc_buf_get+0x194/0x220 [ 29.874529] ? __uart_start.isra.0+0x1b0/0x1b0 [ 29.879097] n_hdlc_send_frames+0x241/0x410 [ 29.883399] n_hdlc_tty_wakeup+0x95/0xb0 [ 29.887434] ? n_hdlc_tty_open+0x4d0/0x4d0 [ 29.891643] tty_wakeup+0xc3/0xf0 [ 29.895072] tty_port_default_wakeup+0x26/0x40 [ 29.899632] serial8250_tx_chars+0x3fe/0xc70 [ 29.904017] serial8250_handle_irq.part.0+0x2c7/0x390 [ 29.909179] serial8250_default_handle_irq+0x8a/0x1f0 [ 29.914341] serial8250_interrupt+0xf3/0x210 [ 29.918722] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 29.924147] ? serial8250_backup_timeout+0x440/0x440 [ 29.929221] __handle_irq_event_percpu+0xee/0x7f0 [ 29.934035] handle_irq_event+0xed/0x240 [ 29.938067] ? handle_irq_event_percpu+0x110/0x110 [ 29.942968] handle_edge_irq+0x224/0xc40 [ 29.947003] handle_irq+0x35/0x50 [ 29.950430] do_IRQ+0x93/0x1d0 [ 29.953595] common_interrupt+0x93/0x93 [ 29.957536] [ 29.959744] RIP: 0010:native_safe_halt+0xe/0x10 [ 29.964387] RSP: 0018:ffff8880b5477e68 EFLAGS: 000002c2 ORIG_RAX: ffffffffffffffc8 [ 29.972077] RAX: 1ffffffff11e13dc RBX: dffffc0000000000 RCX: 0000000000000000 [ 29.979407] RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff8880b5464bc4 [ 29.986647] RBP: ffffffff88f09ed0 R08: 0000000000000000 R09: 0000000000000000 [ 29.993890] R10: 0000000000000000 R11: 0000000000000000 R12: ffffed1016a8c868 [ 30.001133] R13: ffff8880b5464340 R14: 0000000000000000 R15: 0000000000000000 [ 30.008382] default_idle+0x47/0x370 [ 30.012072] do_idle+0x250/0x3c0 [ 30.015409] cpu_startup_entry+0x14/0x20 [ 30.019444] start_secondary+0x4db/0x670 [ 30.023478] ? set_cpu_sibling_map+0x1680/0x1680 [ 30.028207] secondary_startup_64+0xa5/0xb0