===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 6.12.0-syzkaller-09073-g9f16d5e6f220 #0 Not tainted ----------------------------------------------------- kworker/u8:10/6498 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8f336158 (disc_data_lock#2){.?.?}-{3:3}, at: sp_get+0x18/0xf0 drivers/net/hamradio/6pack.c:370 and this task is already holding: ffffffff9ab3d538 (&port_lock_key){-.-.}-{3:3}, at: uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] ffffffff9ab3d538 (&port_lock_key){-.-.}-{3:3}, at: uart_write+0x13b/0xb30 drivers/tty/serial/serial_core.c:626 which would create a new lock dependency: (&port_lock_key){-.-.}-{3:3} -> (disc_data_lock#2){.?.?}-{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.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __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+0x95/0xc80 drivers/tty/serial/8250/8250_port.c:1919 serial8250_default_handle_irq+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:1968 serial8250_interrupt+0x103/0x210 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:247 [inline] call_irq_handler arch/x86/kernel/irq.c:259 [inline] __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:285 common_interrupt+0xba/0xe0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:699 cpuidle_enter_state+0xaa/0x4f0 drivers/cpuidle/cpuidle.c:268 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:389 cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x310/0x3f0 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 start_secondary+0x222/0x2b0 arch/x86/kernel/smpboot.c:314 common_startup_64+0x13e/0x148 to a HARDIRQ-irq-unsafe lock: (disc_data_lock#2){.?.?}-{3:3} ... which became HARDIRQ-irq-unsafe at: ... lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 sp_get+0x18/0xf0 drivers/net/hamradio/6pack.c:370 sixpack_write_wakeup+0x20/0x390 drivers/net/hamradio/6pack.c:391 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+0xde/0x6a0 drivers/tty/tty_ldisc.c:700 __tty_hangup.part.0+0x3f8/0x890 drivers/tty/tty_io.c:624 __tty_hangup drivers/tty/tty_io.c:691 [inline] tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_vhangup drivers/tty/tty_io.c:691 [inline] tty_ioctl+0xf42/0x15d0 drivers/tty/tty_io.c:2743 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/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 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#2); local_irq_disable(); lock(&port_lock_key); lock(disc_data_lock#2); lock(&port_lock_key); *** DEADLOCK *** 6 locks held by kworker/u8:10/6498: #0: ffff88801b081148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3204 #1: ffffc9000e267d80 ((work_completion)(&buf->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff888025470ca0 (&buf->lock){+.+.}-{4:4}, at: flush_to_ldisc+0x31/0x780 drivers/tty/tty_buffer.c:467 #3: ffff88807b39d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1c/0x80 drivers/tty/tty_ldisc.c:263 #4: ffffffff9ab3d538 (&port_lock_key){-.-.}-{3:3}, at: uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] #4: ffffffff9ab3d538 (&port_lock_key){-.-.}-{3:3}, at: uart_write+0x13b/0xb30 drivers/tty/serial/serial_core.c:626 #5: ffff88807b39d0a0 (&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.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __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+0x95/0xc80 drivers/tty/serial/8250/8250_port.c:1919 serial8250_default_handle_irq+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:1968 serial8250_interrupt+0x103/0x210 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:247 [inline] call_irq_handler arch/x86/kernel/irq.c:259 [inline] __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:285 common_interrupt+0xba/0xe0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:699 cpuidle_enter_state+0xaa/0x4f0 drivers/cpuidle/cpuidle.c:268 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:389 cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x310/0x3f0 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 start_secondary+0x222/0x2b0 arch/x86/kernel/smpboot.c:314 common_startup_64+0x13e/0x148 IN-SOFTIRQ-W at: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __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+0x95/0xc80 drivers/tty/serial/8250/8250_port.c:1919 serial8250_default_handle_irq+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:1968 serial8250_interrupt+0x103/0x210 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:247 [inline] call_irq_handler arch/x86/kernel/irq.c:259 [inline] __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:285 common_interrupt+0x61/0xe0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 orc_find arch/x86/kernel/unwind_orc.c:218 [inline] unwind_next_frame+0x22d/0x20c0 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x95/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2342 [inline] slab_free mm/slub.c:4579 [inline] kmem_cache_free+0x152/0x4b0 mm/slub.c:4681 rcu_do_batch kernel/rcu/tree.c:2567 [inline] rcu_core+0x79d/0x14d0 kernel/rcu/tree.c:2823 handle_softirqs+0x213/0x8f0 kernel/softirq.c:554 do_softirq kernel/softirq.c:455 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:442 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:382 local_bh_enable include/linux/bottom_half.h:33 [inline] fpregs_unlock arch/x86/include/asm/fpu/api.h:80 [inline] fpu_clone+0x398/0xd80 arch/x86/kernel/fpu/core.c:634 copy_thread+0x451/0xb80 arch/x86/kernel/process.c:214 copy_process+0x382c/0x8cc0 kernel/fork.c:2384 kernel_clone+0xfd/0x960 kernel/fork.c:2787 __do_sys_vfork+0x89/0xc0 kernel/fork.c:2892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __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+0x307/0x16f0 drivers/tty/serial/8250/8250_port.c:2761 serial8250_set_termios+0x6e/0x80 drivers/tty/serial/8250/8250_port.c:2880 uart_set_options+0x31b/0x5f0 drivers/tty/serial/serial_core.c:2327 serial8250_console_setup+0x18a/0x460 drivers/tty/serial/8250/8250_port.c:3475 univ8250_console_setup+0x1d4/0x2c0 drivers/tty/serial/8250/8250_core.c:428 console_call_setup kernel/printk/printk.c:3773 [inline] console_call_setup kernel/printk/printk.c:3764 [inline] try_enable_preferred_console+0x2fd/0x530 kernel/printk/printk.c:3817 register_console+0x3ac/0x1170 kernel/printk/printk.c:4011 univ8250_console_init+0x5f/0x90 drivers/tty/serial/8250/8250_core.c:513 console_init+0xbb/0x6a0 kernel/printk/printk.c:4292 start_kernel+0x29a/0x4d0 init/main.c:1037 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488 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#2){.?.?}-{3:3} { IN-HARDIRQ-R at: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x3a/0x70 kernel/locking/spinlock.c:228 sp_get+0x18/0xf0 drivers/net/hamradio/6pack.c:370 sixpack_write_wakeup+0x20/0x390 drivers/net/hamradio/6pack.c:391 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x68e/0x860 drivers/tty/serial/8250/8250_port.c:1840 serial8250_handle_irq+0x74d/0xc80 drivers/tty/serial/8250/8250_port.c:1948 serial8250_default_handle_irq+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:1968 serial8250_interrupt+0x103/0x210 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:247 [inline] call_irq_handler arch/x86/kernel/irq.c:259 [inline] __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:285 common_interrupt+0x61/0xe0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] dummy_timer+0x1e49/0x3930 drivers/usb/gadget/udc/dummy_hcd.c:2010 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1803 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1820 handle_softirqs+0x213/0x8f0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:655 irq_exit_rcu+0x9/0x30 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:699 cpuidle_enter_state+0xaa/0x4f0 drivers/cpuidle/cpuidle.c:268 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:389 cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x310/0x3f0 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 rest_init+0x16b/0x2b0 init/main.c:747 start_kernel+0x3e4/0x4d0 init/main.c:1102 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x148 HARDIRQ-ON-R at: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 sp_get+0x18/0xf0 drivers/net/hamradio/6pack.c:370 sixpack_write_wakeup+0x20/0x390 drivers/net/hamradio/6pack.c:391 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+0xde/0x6a0 drivers/tty/tty_ldisc.c:700 __tty_hangup.part.0+0x3f8/0x890 drivers/tty/tty_io.c:624 __tty_hangup drivers/tty/tty_io.c:691 [inline] tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_vhangup drivers/tty/tty_io.c:691 [inline] tty_ioctl+0xf42/0x15d0 drivers/tty/tty_io.c:2743 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/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f IN-SOFTIRQ-R at: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x3a/0x70 kernel/locking/spinlock.c:228 sp_get+0x18/0xf0 drivers/net/hamradio/6pack.c:370 sixpack_write_wakeup+0x20/0x390 drivers/net/hamradio/6pack.c:391 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x68e/0x860 drivers/tty/serial/8250/8250_port.c:1840 serial8250_handle_irq+0x74d/0xc80 drivers/tty/serial/8250/8250_port.c:1948 serial8250_default_handle_irq+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:1968 serial8250_interrupt+0x103/0x210 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:247 [inline] call_irq_handler arch/x86/kernel/irq.c:259 [inline] __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:285 common_interrupt+0x61/0xe0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] dummy_timer+0x1e49/0x3930 drivers/usb/gadget/udc/dummy_hcd.c:2010 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1803 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1820 handle_softirqs+0x213/0x8f0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:655 irq_exit_rcu+0x9/0x30 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:699 cpuidle_enter_state+0xaa/0x4f0 drivers/cpuidle/cpuidle.c:268 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:389 cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x310/0x3f0 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 rest_init+0x16b/0x2b0 init/main.c:747 start_kernel+0x3e4/0x4d0 init/main.c:1102 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x148 SOFTIRQ-ON-R at: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 sp_get+0x18/0xf0 drivers/net/hamradio/6pack.c:370 sixpack_write_wakeup+0x20/0x390 drivers/net/hamradio/6pack.c:391 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+0xde/0x6a0 drivers/tty/tty_ldisc.c:700 __tty_hangup.part.0+0x3f8/0x890 drivers/tty/tty_io.c:624 __tty_hangup drivers/tty/tty_io.c:691 [inline] tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_vhangup drivers/tty/tty_io.c:691 [inline] tty_ioctl+0xf42/0x15d0 drivers/tty/tty_io.c:2743 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/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0x36/0x50 kernel/locking/spinlock.c:326 sixpack_close+0x1e/0x2f0 drivers/net/hamradio/6pack.c:641 tty_ldisc_close+0x111/0x1a0 drivers/tty/tty_ldisc.c:455 tty_ldisc_kill+0x8e/0x150 drivers/tty/tty_ldisc.c:613 tty_ldisc_hangup+0x311/0x6a0 drivers/tty/tty_ldisc.c:729 __tty_hangup.part.0+0x3f8/0x890 drivers/tty/tty_io.c:624 __tty_hangup drivers/tty/tty_io.c:691 [inline] tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_vhangup drivers/tty/tty_io.c:691 [inline] tty_ioctl+0xf42/0x15d0 drivers/tty/tty_io.c:2743 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/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 sp_get+0x18/0xf0 drivers/net/hamradio/6pack.c:370 sixpack_write_wakeup+0x20/0x390 drivers/net/hamradio/6pack.c:391 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+0xde/0x6a0 drivers/tty/tty_ldisc.c:700 __tty_hangup.part.0+0x3f8/0x890 drivers/tty/tty_io.c:624 __tty_hangup drivers/tty/tty_io.c:691 [inline] tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_vhangup drivers/tty/tty_io.c:691 [inline] tty_ioctl+0xf42/0x15d0 drivers/tty/tty_io.c:2743 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/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] disc_data_lock+0x18/0xfe0 ... acquired at: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 sp_get+0x18/0xf0 drivers/net/hamradio/6pack.c:370 sixpack_write_wakeup+0x20/0x390 drivers/net/hamradio/6pack.c:391 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x68e/0x860 drivers/tty/serial/8250/8250_port.c:1840 __start_tx+0x3e9/0x4a0 drivers/tty/serial/8250/8250_port.c:1546 serial8250_start_tx+0x363/0x530 drivers/tty/serial/8250/8250_port.c:1655 __uart_start+0x292/0x4c0 drivers/tty/serial/serial_core.c:160 uart_write+0x218/0xb30 drivers/tty/serial/serial_core.c:635 decode_prio_command drivers/net/hamradio/6pack.c:868 [inline] sixpack_decode drivers/net/hamradio/6pack.c:943 [inline] sixpack_receive_buf drivers/net/hamradio/6pack.c:447 [inline] sixpack_receive_buf+0x3d7/0x1c80 drivers/net/hamradio/6pack.c:424 tty_ldisc_receive_buf+0x153/0x190 drivers/tty/tty_buffer.c:391 tty_port_default_receive_buf+0x70/0xb0 drivers/tty/tty_port.c:37 receive_buf drivers/tty/tty_buffer.c:445 [inline] flush_to_ldisc+0x264/0x780 drivers/tty/tty_buffer.c:495 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 stack backtrace: CPU: 0 UID: 0 PID: 6498 Comm: kworker/u8:10 Not tainted 6.12.0-syzkaller-09073-g9f16d5e6f220 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound flush_to_ldisc 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:2647 [inline] check_irq_usage+0xf22/0x1290 kernel/locking/lockdep.c:2888 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain kernel/locking/lockdep.c:3904 [inline] __lock_acquire+0x24b4/0x3c40 kernel/locking/lockdep.c:5226 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 sp_get+0x18/0xf0 drivers/net/hamradio/6pack.c:370 sixpack_write_wakeup+0x20/0x390 drivers/net/hamradio/6pack.c:391 tty_wakeup+0xe5/0x120 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x68e/0x860 drivers/tty/serial/8250/8250_port.c:1840 __start_tx+0x3e9/0x4a0 drivers/tty/serial/8250/8250_port.c:1546 serial8250_start_tx+0x363/0x530 drivers/tty/serial/8250/8250_port.c:1655 __uart_start+0x292/0x4c0 drivers/tty/serial/serial_core.c:160 uart_write+0x218/0xb30 drivers/tty/serial/serial_core.c:635 decode_prio_command drivers/net/hamradio/6pack.c:868 [inline] sixpack_decode drivers/net/hamradio/6pack.c:943 [inline] sixpack_receive_buf drivers/net/hamradio/6pack.c:447 [inline] sixpack_receive_buf+0x3d7/0x1c80 drivers/net/hamradio/6pack.c:424 tty_ldisc_receive_buf+0x153/0x190 drivers/tty/tty_buffer.c:391 tty_port_default_receive_buf+0x70/0xb0 drivers/tty/tty_port.c:37 receive_buf drivers/tty/tty_buffer.c:445 [inline] flush_to_ldisc+0x264/0x780 drivers/tty/tty_buffer.c:495 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244