===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 6.15.0-syzkaller-02443-g015a99fa7665 #0 Not tainted ----------------------------------------------------- kworker/u8:5/19598 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8ead8098 (disc_data_lock#3){.?.+}-{3:3}, at: sp_get drivers/net/hamradio/6pack.c:370 [inline] ffffffff8ead8098 (disc_data_lock#3){.?.+}-{3:3}, at: sixpack_write_wakeup+0x30/0x480 drivers/net/hamradio/6pack.c:391 and this task is already holding: ffffffff99b53518 (&port_lock_key){-.-.}-{3:3}, at: uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] ffffffff99b53518 (&port_lock_key){-.-.}-{3:3}, at: uart_write+0xfa/0xa40 drivers/tty/serial/serial_core.c:626 which would create a new lock dependency: (&port_lock_key){-.-.}-{3:3} -> (disc_data_lock#3){.?.+}-{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+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] serial8250_handle_irq+0x6b/0xbb0 drivers/tty/serial/8250/8250_port.c:1921 serial8250_default_handle_irq+0xbf/0x1b0 drivers/tty/serial/8250/8250_port.c:1970 serial8250_interrupt+0xa5/0x1d0 drivers/tty/serial/8250/8250_core.c:86 __handle_irq_event_percpu+0x28c/0x980 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x267/0x9c0 kernel/irq/chip.c:789 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+0x140/0x250 arch/x86/kernel/irq.c:292 common_interrupt+0xb6/0xe0 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+0x13/0x20 arch/x86/kernel/paravirt.c:81 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:743 default_idle_call+0x74/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x1e8/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423 rest_init+0x2de/0x300 init/main.c:743 start_kernel+0x478/0x500 init/main.c:1099 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x147 to a HARDIRQ-irq-unsafe lock: (disc_data_lock#3){.?.+}-{3:3} ... which became HARDIRQ-irq-unsafe at: ... lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 sp_get drivers/net/hamradio/6pack.c:370 [inline] sixpack_write_wakeup+0x30/0x480 drivers/net/hamradio/6pack.c:391 tty_wakeup+0xbe/0x100 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0xa2/0xf0 drivers/tty/tty_port.c:69 tty_ldisc_hangup+0xdd/0x4b0 drivers/tty/tty_ldisc.c:700 __tty_hangup+0x3df/0x650 drivers/tty/tty_io.c:624 tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_ioctl+0x757/0xde0 drivers/tty/tty_io.c:2742 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 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#3); local_irq_disable(); lock(&port_lock_key); lock(disc_data_lock#3); lock(&port_lock_key); *** DEADLOCK *** 6 locks held by kworker/u8:5/19598: #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000b17fbc0 ((work_completion)(&buf->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000b17fbc0 ((work_completion)(&buf->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff8880244a8ca0 (&buf->lock){+.+.}-{4:4}, at: flush_to_ldisc+0x38/0x810 drivers/tty/tty_buffer.c:467 #3: ffff8880273160a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1c/0x90 drivers/tty/tty_ldisc.c:263 #4: ffffffff99b53518 (&port_lock_key){-.-.}-{3:3}, at: uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] #4: ffffffff99b53518 (&port_lock_key){-.-.}-{3:3}, at: uart_write+0xfa/0xa40 drivers/tty/serial/serial_core.c:626 #5: ffff8880273160a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1c/0x90 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+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] serial8250_handle_irq+0x6b/0xbb0 drivers/tty/serial/8250/8250_port.c:1921 serial8250_default_handle_irq+0xbf/0x1b0 drivers/tty/serial/8250/8250_port.c:1970 serial8250_interrupt+0xa5/0x1d0 drivers/tty/serial/8250/8250_core.c:86 __handle_irq_event_percpu+0x28c/0x980 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x267/0x9c0 kernel/irq/chip.c:789 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+0x140/0x250 arch/x86/kernel/irq.c:292 common_interrupt+0xb6/0xe0 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+0x13/0x20 arch/x86/kernel/paravirt.c:81 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:743 default_idle_call+0x74/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x1e8/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423 rest_init+0x2de/0x300 init/main.c:743 start_kernel+0x478/0x500 init/main.c:1099 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x147 IN-SOFTIRQ-W at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] serial8250_handle_irq+0x6b/0xbb0 drivers/tty/serial/8250/8250_port.c:1921 serial8250_default_handle_irq+0xbf/0x1b0 drivers/tty/serial/8250/8250_port.c:1970 serial8250_interrupt+0xa5/0x1d0 drivers/tty/serial/8250/8250_core.c:86 __handle_irq_event_percpu+0x28c/0x980 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x267/0x9c0 kernel/irq/chip.c:789 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+0x140/0x250 arch/x86/kernel/irq.c:292 common_interrupt+0x5e/0xe0 arch/x86/kernel/irq.c:285 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline] raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline] rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x5a/0xb0 kernel/rcu/tree.c:745 rcu_read_lock include/linux/rcupdate.h:842 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd4/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2380 [inline] slab_free mm/slub.c:4642 [inline] kmem_cache_free+0x18f/0x400 mm/slub.c:4744 rcu_do_batch kernel/rcu/tree.c:2576 [inline] rcu_core+0xca8/0x1710 kernel/rcu/tree.c:2832 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4339 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] tomoyo_get_name+0x20c/0x590 security/tomoyo/memory.c:173 tomoyo_parse_name_union+0xd9/0x130 security/tomoyo/util.c:260 tomoyo_update_path_acl security/tomoyo/file.c:395 [inline] tomoyo_write_file+0x359/0xbb0 security/tomoyo/file.c:1022 tomoyo_write_domain2 security/tomoyo/common.c:1144 [inline] tomoyo_add_entry security/tomoyo/common.c:2143 [inline] tomoyo_supervisor+0x116a/0x1480 security/tomoyo/common.c:2204 tomoyo_audit_path_log security/tomoyo/file.c:168 [inline] tomoyo_path_permission+0x25a/0x380 security/tomoyo/file.c:587 tomoyo_path_perm+0x392/0x4b0 security/tomoyo/file.c:838 security_inode_getattr+0x12f/0x330 security/security.c:2377 vfs_getattr fs/stat.c:259 [inline] vfs_statx_path fs/stat.c:299 [inline] vfs_statx+0x18e/0x550 fs/stat.c:356 vfs_fstatat+0x118/0x170 fs/stat.c:375 __do_sys_newfstatat fs/stat.c:542 [inline] __se_sys_newfstatat fs/stat.c:536 [inline] __x64_sys_newfstatat+0x116/0x190 fs/stat.c:536 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:715 [inline] serial8250_do_set_termios+0x4bb/0x1c20 drivers/tty/serial/8250/8250_port.c:2778 uart_set_options+0x3c2/0x5b0 drivers/tty/serial/serial_core.c:2310 serial8250_console_setup+0x2f4/0x3c0 drivers/tty/serial/8250/8250_port.c:3519 univ8250_console_setup+0x43a/0x540 drivers/tty/serial/8250/8250_core.c:428 console_call_setup kernel/printk/printk.c:3799 [inline] try_enable_preferred_console+0x4e4/0x650 kernel/printk/printk.c:3843 register_console+0x551/0xf90 kernel/printk/printk.c:4037 univ8250_console_init+0x52/0x90 drivers/tty/serial/8250/8250_core.c:513 console_init+0x1a1/0x670 kernel/printk/printk.c:4323 start_kernel+0x2cc/0x500 init/main.c:1034 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x147 } ... key at: [] port_lock_key+0x0/0x20 the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: -> (disc_data_lock#3){.?.+}-{3:3} { IN-HARDIRQ-R at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 sp_get drivers/net/hamradio/6pack.c:370 [inline] sixpack_write_wakeup+0x30/0x480 drivers/net/hamradio/6pack.c:391 tty_wakeup+0xbe/0x100 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0xa2/0xf0 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x72e/0x970 drivers/tty/serial/8250/8250_port.c:1842 serial8250_handle_irq+0x633/0xbb0 drivers/tty/serial/8250/8250_port.c:1950 serial8250_default_handle_irq+0xbf/0x1b0 drivers/tty/serial/8250/8250_port.c:1970 serial8250_interrupt+0xa5/0x1d0 drivers/tty/serial/8250/8250_core.c:86 __handle_irq_event_percpu+0x28c/0x980 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x267/0x9c0 kernel/irq/chip.c:789 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+0x140/0x250 arch/x86/kernel/irq.c:292 common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:285 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 memory_is_nonzero mm/kasan/generic.c:103 [inline] memory_is_poisoned_n mm/kasan/generic.c:129 [inline] memory_is_poisoned mm/kasan/generic.c:161 [inline] check_region_inline mm/kasan/generic.c:180 [inline] kasan_check_range+0x89/0x2c0 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1301 [inline] queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] do_raw_spin_lock+0x121/0x290 kernel/locking/spinlock_debug.c:116 spin_lock include/linux/spinlock.h:351 [inline] wg_ratelimiter_gc_entries+0x5d/0x450 drivers/net/wireguard/ratelimiter.c:63 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 HARDIRQ-ON-R at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 sp_get drivers/net/hamradio/6pack.c:370 [inline] sixpack_write_wakeup+0x30/0x480 drivers/net/hamradio/6pack.c:391 tty_wakeup+0xbe/0x100 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0xa2/0xf0 drivers/tty/tty_port.c:69 tty_ldisc_hangup+0xdd/0x4b0 drivers/tty/tty_ldisc.c:700 __tty_hangup+0x3df/0x650 drivers/tty/tty_io.c:624 tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_ioctl+0x757/0xde0 drivers/tty/tty_io.c:2742 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f SOFTIRQ-ON-R at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 sp_get drivers/net/hamradio/6pack.c:370 [inline] sixpack_write_wakeup+0x30/0x480 drivers/net/hamradio/6pack.c:391 tty_wakeup+0xbe/0x100 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0xa2/0xf0 drivers/tty/tty_port.c:69 tty_ldisc_hangup+0xdd/0x4b0 drivers/tty/tty_ldisc.c:700 __tty_hangup+0x3df/0x650 drivers/tty/tty_io.c:624 tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_ioctl+0x757/0xde0 drivers/tty/tty_io.c:2742 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:326 sixpack_close+0x2c/0x280 drivers/net/hamradio/6pack.c:641 tty_ldisc_kill+0xa3/0x1a0 drivers/tty/tty_ldisc.c:613 tty_ldisc_hangup+0x3a2/0x4b0 drivers/tty/tty_ldisc.c:729 __tty_hangup+0x3df/0x650 drivers/tty/tty_io.c:624 tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_ioctl+0x757/0xde0 drivers/tty/tty_io.c:2742 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 sp_get drivers/net/hamradio/6pack.c:370 [inline] sixpack_write_wakeup+0x30/0x480 drivers/net/hamradio/6pack.c:391 tty_wakeup+0xbe/0x100 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0xa2/0xf0 drivers/tty/tty_port.c:69 tty_ldisc_hangup+0xdd/0x4b0 drivers/tty/tty_ldisc.c:700 __tty_hangup+0x3df/0x650 drivers/tty/tty_io.c:624 tty_vhangup drivers/tty/tty_io.c:694 [inline] tty_ioctl+0x757/0xde0 drivers/tty/tty_io.c:2742 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] disc_data_lock+0x18/0x100 6pack.c:-1 ... acquired at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 sp_get drivers/net/hamradio/6pack.c:370 [inline] sixpack_write_wakeup+0x30/0x480 drivers/net/hamradio/6pack.c:391 tty_wakeup+0xbe/0x100 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0xa2/0xf0 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x72e/0x970 drivers/tty/serial/8250/8250_port.c:1842 __start_tx+0x33b/0x480 drivers/tty/serial/8250/8250_port.c:1547 __uart_start+0x23f/0x440 drivers/tty/serial/serial_core.c:160 uart_write+0x278/0xa40 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+0x447/0x1450 drivers/net/hamradio/6pack.c:447 tty_ldisc_receive_buf+0x119/0x160 drivers/tty/tty_buffer.c:391 tty_port_default_receive_buf+0x6e/0xa0 drivers/tty/tty_port.c:37 receive_buf drivers/tty/tty_buffer.c:445 [inline] flush_to_ldisc+0x2c2/0x810 drivers/tty/tty_buffer.c:495 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 stack backtrace: CPU: 0 UID: 0 PID: 19598 Comm: kworker/u8:5 Not tainted 6.15.0-syzkaller-02443-g015a99fa7665 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound flush_to_ldisc Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_bad_irq_dependency kernel/locking/lockdep.c:2619 [inline] check_irq_usage kernel/locking/lockdep.c:2860 [inline] check_prev_add kernel/locking/lockdep.c:3172 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0x1f05/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 sp_get drivers/net/hamradio/6pack.c:370 [inline] sixpack_write_wakeup+0x30/0x480 drivers/net/hamradio/6pack.c:391 tty_wakeup+0xbe/0x100 drivers/tty/tty_io.c:517 tty_port_default_wakeup+0xa2/0xf0 drivers/tty/tty_port.c:69 serial8250_tx_chars+0x72e/0x970 drivers/tty/serial/8250/8250_port.c:1842 __start_tx+0x33b/0x480 drivers/tty/serial/8250/8250_port.c:1547 __uart_start+0x23f/0x440 drivers/tty/serial/serial_core.c:160 uart_write+0x278/0xa40 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+0x447/0x1450 drivers/net/hamradio/6pack.c:447 tty_ldisc_receive_buf+0x119/0x160 drivers/tty/tty_buffer.c:391 tty_port_default_receive_buf+0x6e/0xa0 drivers/tty/tty_port.c:37 receive_buf drivers/tty/tty_buffer.c:445 [inline] flush_to_ldisc+0x2c2/0x810 drivers/tty/tty_buffer.c:495 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245