ipt_ECN: cannot use TCP operations on a non-tcp rule IPVS: ftp: loaded support on port[0] = 21 ============================================ WARNING: possible recursive locking detected 4.14.290-syzkaller #0 Not tainted -------------------------------------------- systemd-udevd/9744 is trying to acquire lock: (&port_lock_key){-.-.}, at: [] uart_write+0x109/0x560 drivers/tty/serial/serial_core.c:611 but task is already holding lock: (&port_lock_key){-.-.}, at: [] serial8250_handle_irq.part.0+0x20/0x330 drivers/tty/serial/8250/8250_port.c:1891 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&port_lock_key); lock(&port_lock_key); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by systemd-udevd/9744: #0: (&(&i->lock)->rlock){-.-.}, at: [] spin_lock include/linux/spinlock.h:317 [inline] #0: (&(&i->lock)->rlock){-.-.}, at: [] serial8250_interrupt+0x3a/0x210 drivers/tty/serial/8250/8250_core.c:119 #1: (&port_lock_key){-.-.}, at: [] serial8250_handle_irq.part.0+0x20/0x330 drivers/tty/serial/8250/8250_port.c:1891 #2: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref+0x1b/0x80 drivers/tty/tty_ldisc.c:305 stack backtrace: CPU: 1 PID: 9744 Comm: systemd-udevd Not tainted 4.14.290-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_deadlock_bug kernel/locking/lockdep.c:1800 [inline] check_deadlock kernel/locking/lockdep.c:1847 [inline] validate_chain kernel/locking/lockdep.c:2448 [inline] __lock_acquire.cold+0x180/0x97c kernel/locking/lockdep.c:3491 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:160 uart_write+0x109/0x560 drivers/tty/serial/serial_core.c:611 n_hdlc_send_frames+0x241/0x410 drivers/tty/n_hdlc.c:404 n_hdlc_tty_wakeup+0x95/0xb0 drivers/tty/n_hdlc.c:480 tty_wakeup+0xc3/0xf0 drivers/tty/tty_io.c:533 tty_port_default_wakeup+0x26/0x40 drivers/tty/tty_port.c:49 serial8250_tx_chars+0x3fe/0xc70 drivers/tty/serial/8250/8250_port.c:1828 serial8250_handle_irq.part.0+0x28d/0x330 drivers/tty/serial/8250/8250_port.c:1915 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1888 [inline] serial8250_default_handle_irq+0x8a/0x1f0 drivers/tty/serial/8250/8250_port.c:1931 serial8250_interrupt+0xf3/0x210 drivers/tty/serial/8250/8250_core.c:129 __handle_irq_event_percpu+0xee/0x7f0 kernel/irq/handle.c:147 handle_irq_event_percpu kernel/irq/handle.c:187 [inline] handle_irq_event+0xed/0x240 kernel/irq/handle.c:204 handle_edge_irq+0x224/0xc40 kernel/irq/chip.c:770 generic_handle_irq_desc include/linux/irqdesc.h:159 [inline] handle_irq+0x35/0x50 arch/x86/kernel/irq_64.c:87 do_IRQ+0x93/0x1d0 arch/x86/kernel/irq.c:230 common_interrupt+0x93/0x93 arch/x86/entry/entry_64.S:576 RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:774 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:796 [inline] RIP: 0010:kmem_cache_free+0x34/0x2b0 mm/slab.c:3754 RSP: 0018:ffff888096967b78 EFLAGS: 00000286 ORIG_RAX: ffffffffffffffc8 RAX: 0000000000000286 RBX: ffff88808fb46b40 RCX: 1ffff110165558e0 RDX: 0000000000000000 RSI: ffff88808fb46b40 RDI: ffff88823f8c1200 RBP: ffff88823f8c1200 R08: ffffffff8b9d59e0 R09: 0000000000000000 R10: 0000000000000000 R11: ffff8880b2aac040 R12: ffff88808fb46b5c R13: ffff88823f8c1200 R14: ffff88808fb46b40 R15: ffff888096967c50 putname+0xcd/0x110 fs/namei.c:259 filename_lookup+0x37b/0x510 fs/namei.c:2386 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xd1/0x180 fs/stat.c:185 vfs_stat include/linux/fs.h:3067 [inline] SYSC_newstat fs/stat.c:336 [inline] SyS_newstat+0x83/0xe0 fs/stat.c:332 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fc391b23295 RSP: 002b:00007fff65eecb78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000124 RCX: 00007fc391b23295 RDX: 00007fff65eecb80 RSI: 00007fff65eecb80 RDI: 00007fff65eecc30 RBP: 00007fff65eeccb0 R08: 000000000000c0c0 R09: 0000560aa0024228 R10: 00007fff65eeccc0 R11: 0000000000000246 R12: 00007fff65eecce0 R13: 00007fff65eecce0 R14: 0000560aa001f760 R15: 000000000000000e RDS: rds_bind could not find a transport for 172.20.20.0, load rds_tcp or rds_rdma?