===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 6.15.0-rc6-syzkaller-00346-g5723cc3450bc #0 Not tainted ----------------------------------------------------- syz.0.2194/13808 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8f57ea58 (disc_data_lock#4){.+.+}-{3:3}, at: ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:137 and this task is already holding: ffffffff9adff0b8 (&port_lock_key){-.-.}-{3:3}, at: spin_lock_irq include/linux/spinlock.h:376 [inline] ffffffff9adff0b8 (&port_lock_key){-.-.}-{3:3}, at: uart_port_lock_irq include/linux/serial_core.h:704 [inline] ffffffff9adff0b8 (&port_lock_key){-.-.}-{3:3}, at: uart_carrier_raised+0xf8/0x7b0 drivers/tty/serial/serial_core.c:1928 which would create a new lock dependency: (&port_lock_key){-.-.}-{3:3} -> (disc_data_lock#4){.+.+}-{3:3} but this new dependency connects a HARDIRQ-irq-safe lock: (&port_lock_key){-.-.}-{3:3} ... which became HARDIRQ-irq-safe at: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] serial8250_handle_irq+0x95/0xcb0 drivers/tty/serial/8250/8250_port.c:1921 serial8250_default_handle_irq+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:1970 serial8250_interrupt+0x106/0x210 drivers/tty/serial/8250/8250_core.c:86 __handle_irq_event_percpu+0x229/0x7d0 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x263/0xd10 kernel/irq/chip.c:831 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:254 [inline] call_irq_handler arch/x86/kernel/irq.c:266 [inline] __common_interrupt+0xe2/0x250 arch/x86/kernel/irq.c:292 common_interrupt+0xba/0xe0 arch/x86/kernel/irq.c:285 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:80 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:748 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 to a HARDIRQ-irq-unsafe lock: (disc_data_lock#4){.+.+}-{3:3} ... which became HARDIRQ-irq-unsafe at: ... lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:137 ppp_asynctty_wakeup+0x18/0xb0 drivers/net/ppp/ppp_async.c:353 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 uart_flush_buffer+0x37b/0x890 drivers/tty/serial/serial_core.c:688 tty_driver_flush_buffer+0x61/0x80 drivers/tty/tty_ioctl.c:85 tty_ldisc_hangup+0xe7/0x730 drivers/tty/tty_ldisc.c:700 __tty_hangup.part.0+0x3eb/0x890 drivers/tty/tty_io.c:624 __tty_hangup drivers/tty/tty_io.c:2725 [inline] tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_vhangup drivers/tty/tty_io.c:691 [inline] tty_ioctl+0x10bf/0x1610 drivers/tty/tty_io.c:2742 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(disc_data_lock#4); local_irq_disable(); lock(&port_lock_key); lock(disc_data_lock#4); lock(&port_lock_key); *** DEADLOCK *** 3 locks held by syz.0.2194/13808: #0: ffff888024fe01c0 (&tty->legacy_mutex){+.+.}-{4:4}, at: tty_lock_interruptible+0x75/0xe0 drivers/tty/tty_mutex.c:27 #1: ffffffff9adff0b8 (&port_lock_key){-.-.}-{3:3}, at: spin_lock_irq include/linux/spinlock.h:376 [inline] #1: ffffffff9adff0b8 (&port_lock_key){-.-.}-{3:3}, at: uart_port_lock_irq include/linux/serial_core.h:704 [inline] #1: ffffffff9adff0b8 (&port_lock_key){-.-.}-{3:3}, at: uart_carrier_raised+0xf8/0x7b0 drivers/tty/serial/serial_core.c:1928 #2: ffff888024fe00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1c/0x80 drivers/tty/tty_ldisc.c:263 the dependencies between HARDIRQ-irq-safe lock and the holding lock: -> (&port_lock_key){-.-.}-{3:3} { IN-HARDIRQ-W at: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] serial8250_handle_irq+0x95/0xcb0 drivers/tty/serial/8250/8250_port.c:1921 serial8250_default_handle_irq+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:1970 serial8250_interrupt+0x106/0x210 drivers/tty/serial/8250/8250_core.c:86 __handle_irq_event_percpu+0x229/0x7d0 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x263/0xd10 kernel/irq/chip.c:831 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:254 [inline] call_irq_handler arch/x86/kernel/irq.c:266 [inline] __common_interrupt+0xe2/0x250 arch/x86/kernel/irq.c:292 common_interrupt+0xba/0xe0 arch/x86/kernel/irq.c:285 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:80 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:748 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 IN-SOFTIRQ-W at: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] serial8250_handle_irq+0x95/0xcb0 drivers/tty/serial/8250/8250_port.c:1921 serial8250_default_handle_irq+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:1970 serial8250_interrupt+0x106/0x210 drivers/tty/serial/8250/8250_core.c:86 __handle_irq_event_percpu+0x229/0x7d0 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x263/0xd10 kernel/irq/chip.c:831 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:254 [inline] call_irq_handler arch/x86/kernel/irq.c:266 [inline] __common_interrupt+0xe2/0x250 arch/x86/kernel/irq.c:292 common_interrupt+0x61/0xe0 arch/x86/kernel/irq.c:285 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 variable_ffs arch/x86/include/asm/bitops.h:321 [inline] handle_softirqs+0x1dd/0x8e0 kernel/softirq.c:567 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 common_interrupt+0xbf/0xe0 arch/x86/kernel/irq.c:285 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:80 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:748 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] serial8250_do_set_termios+0x310/0x1710 drivers/tty/serial/8250/8250_port.c:2778 serial8250_set_termios+0x6e/0x80 drivers/tty/serial/8250/8250_port.c:2903 uart_set_options+0x31a/0x5f0 drivers/tty/serial/serial_core.c:2310 serial8250_console_setup+0x189/0x450 drivers/tty/serial/8250/8250_port.c:3519 univ8250_console_setup+0x1eb/0x2e0 drivers/tty/serial/8250/8250_core.c:428 console_call_setup kernel/printk/printk.c:3799 [inline] console_call_setup kernel/printk/printk.c:3790 [inline] try_enable_preferred_console+0x2fd/0x530 kernel/printk/printk.c:3843 register_console+0x3ab/0x11b0 kernel/printk/printk.c:4037 univ8250_console_init+0x5f/0x90 drivers/tty/serial/8250/8250_core.c:513 console_init+0x14f/0x680 kernel/printk/printk.c:4323 start_kernel+0x29f/0x4d0 init/main.c:1034 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:513 x86_64_start_kernel+0xb0/0xc0 arch/x86/kernel/head64.c:494 common_startup_64+0x13e/0x148 } ... key at: [] port_lock_key+0x0/0x40 the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: -> (disc_data_lock#4){.+.+}-{3:3} { HARDIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:137 ppp_asynctty_wakeup+0x18/0xb0 drivers/net/ppp/ppp_async.c:353 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 uart_flush_buffer+0x37b/0x890 drivers/tty/serial/serial_core.c:688 tty_driver_flush_buffer+0x61/0x80 drivers/tty/tty_ioctl.c:85 tty_ldisc_hangup+0xe7/0x730 drivers/tty/tty_ldisc.c:700 __tty_hangup.part.0+0x3eb/0x890 drivers/tty/tty_io.c:624 __tty_hangup drivers/tty/tty_io.c:2725 [inline] tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_vhangup drivers/tty/tty_io.c:691 [inline] tty_ioctl+0x10bf/0x1610 drivers/tty/tty_io.c:2742 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f SOFTIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:137 ppp_asynctty_wakeup+0x18/0xb0 drivers/net/ppp/ppp_async.c:353 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 uart_flush_buffer+0x37b/0x890 drivers/tty/serial/serial_core.c:688 tty_driver_flush_buffer+0x61/0x80 drivers/tty/tty_ioctl.c:85 tty_ldisc_hangup+0xe7/0x730 drivers/tty/tty_ldisc.c:700 __tty_hangup.part.0+0x3eb/0x890 drivers/tty/tty_io.c:624 __tty_hangup drivers/tty/tty_io.c:2725 [inline] tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_vhangup drivers/tty/tty_io.c:691 [inline] tty_ioctl+0x10bf/0x1610 drivers/tty/tty_io.c:2742 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0x36/0x50 kernel/locking/spinlock.c:326 ppp_asynctty_close+0x1c/0x1b0 drivers/net/ppp/ppp_async.c:220 tty_ldisc_hangup+0x1a0/0x730 drivers/tty/tty_ldisc.c:705 __tty_hangup.part.0+0x3eb/0x890 drivers/tty/tty_io.c:624 __tty_hangup drivers/tty/tty_io.c:2725 [inline] tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_vhangup drivers/tty/tty_io.c:691 [inline] tty_ioctl+0x10bf/0x1610 drivers/tty/tty_io.c:2742 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:137 ppp_asynctty_wakeup+0x18/0xb0 drivers/net/ppp/ppp_async.c:353 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 uart_flush_buffer+0x37b/0x890 drivers/tty/serial/serial_core.c:688 tty_driver_flush_buffer+0x61/0x80 drivers/tty/tty_ioctl.c:85 tty_ldisc_hangup+0xe7/0x730 drivers/tty/tty_ldisc.c:700 __tty_hangup.part.0+0x3eb/0x890 drivers/tty/tty_io.c:624 __tty_hangup drivers/tty/tty_io.c:2725 [inline] tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_vhangup drivers/tty/tty_io.c:691 [inline] tty_ioctl+0x10bf/0x1610 drivers/tty/tty_io.c:2742 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] disc_data_lock+0x18/0x60 ppp_async.c:-1 ... acquired at: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:137 ppp_asynctty_wakeup+0x18/0xb0 drivers/net/ppp/ppp_async.c:353 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 uart_write_wakeup drivers/tty/serial/serial_core.c:120 [inline] uart_handle_cts_change+0x1e5/0x300 drivers/tty/serial/serial_core.c:3484 serial8250_modem_status+0x284/0x300 drivers/tty/serial/8250/8250_port.c:1872 serial8250_do_get_mctrl+0xb7/0x330 drivers/tty/serial/8250/8250_port.c:2025 serial8250_get_mctrl+0x5c/0x80 drivers/tty/serial/8250/8250_port.c:2040 uart_carrier_raised+0x223/0x7b0 drivers/tty/serial/serial_core.c:1930 tty_port_carrier_raised drivers/tty/tty_port.c:451 [inline] tty_port_block_til_ready+0x3a5/0x8f0 drivers/tty/tty_port.c:570 tty_port_open+0x19c/0x1f0 drivers/tty/tty_port.c:794 uart_open+0x41/0x60 drivers/tty/serial/serial_core.c:1974 tty_open+0x3e1/0xf90 drivers/tty/tty_io.c:2146 chrdev_open+0x234/0x6a0 fs/char_dev.c:414 do_dentry_open+0x744/0x1c10 fs/open.c:956 vfs_open+0x82/0x3f0 fs/open.c:1086 do_open fs/namei.c:3880 [inline] path_openat+0x1e5e/0x2d40 fs/namei.c:4039 do_filp_open+0x20b/0x470 fs/namei.c:4066 do_sys_openat2+0x11b/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1455 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f stack backtrace: CPU: 1 UID: 0 PID: 13808 Comm: syz.0.2194 Not tainted 6.15.0-rc6-syzkaller-00346-g5723cc3450bc #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_bad_irq_dependency kernel/locking/lockdep.c:2652 [inline] check_irq_usage+0x7dc/0x920 kernel/locking/lockdep.c:2893 check_prev_add kernel/locking/lockdep.c:3170 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain kernel/locking/lockdep.c:3909 [inline] __lock_acquire+0x1189/0x1ba0 kernel/locking/lockdep.c:5235 lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 ap_get+0x18/0xf0 drivers/net/ppp/ppp_async.c:137 ppp_asynctty_wakeup+0x18/0xb0 drivers/net/ppp/ppp_async.c:353 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 uart_write_wakeup drivers/tty/serial/serial_core.c:120 [inline] uart_handle_cts_change+0x1e5/0x300 drivers/tty/serial/serial_core.c:3484 serial8250_modem_status+0x284/0x300 drivers/tty/serial/8250/8250_port.c:1872 serial8250_do_get_mctrl+0xb7/0x330 drivers/tty/serial/8250/8250_port.c:2025 serial8250_get_mctrl+0x5c/0x80 drivers/tty/serial/8250/8250_port.c:2040 uart_carrier_raised+0x223/0x7b0 drivers/tty/serial/serial_core.c:1930 tty_port_carrier_raised drivers/tty/tty_port.c:451 [inline] tty_port_block_til_ready+0x3a5/0x8f0 drivers/tty/tty_port.c:570 tty_port_open+0x19c/0x1f0 drivers/tty/tty_port.c:794 uart_open+0x41/0x60 drivers/tty/serial/serial_core.c:1974 tty_open+0x3e1/0xf90 drivers/tty/tty_io.c:2146 chrdev_open+0x234/0x6a0 fs/char_dev.c:414 do_dentry_open+0x744/0x1c10 fs/open.c:956 vfs_open+0x82/0x3f0 fs/open.c:1086 do_open fs/namei.c:3880 [inline] path_openat+0x1e5e/0x2d40 fs/namei.c:4039 do_filp_open+0x20b/0x470 fs/namei.c:4066 do_sys_openat2+0x11b/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1455 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fac4db8e969 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fac4e9b0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fac4ddb6080 RCX: 00007fac4db8e969 RDX: 0000000000002000 RSI: 0000200000000000 RDI: ffffffffffffff9c RBP: 00007fac4dc10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fac4ddb6080 R15: 00007fff75c2d048