================================ WARNING: inconsistent lock state syzkaller #0 Tainted: G L -------------------------------- inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. syz.6.5949/31470 [HC0[0]:SC0[2]:HE1:SE0] takes: ffff888031eb1868 (&dev->spinlock){?.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:347 [inline] ffff888031eb1868 (&dev->spinlock){?.-.}-{3:3}, at: waveform_ao_cancel+0x8d/0x120 drivers/comedi/drivers/comedi_test.c:628 {IN-HARDIRQ-W} state was registered at: lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:341 [inline] das16m1_interrupt+0x5e/0x180 drivers/comedi/drivers/das16m1.c:460 __handle_irq_event_percpu+0x227/0x9e0 kernel/irq/handle.c:209 handle_irq_event_percpu kernel/irq/handle.c:246 [inline] handle_irq_event+0x8b/0x1e0 kernel/irq/handle.c:263 handle_edge_irq+0x23b/0xa10 kernel/irq/chip.c:855 generic_handle_irq_desc include/linux/irqdesc.h:186 [inline] handle_irq arch/x86/kernel/irq.c:262 [inline] call_irq_handler arch/x86/kernel/irq.c:-1 [inline] __common_interrupt+0x141/0x1f0 arch/x86/kernel/irq.c:333 common_interrupt+0xb6/0xe0 arch/x86/kernel/irq.c:326 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688 __preempt_count_add arch/x86/include/asm/preempt.h:80 [inline] rcu_is_watching+0x10/0xb0 kernel/rcu/tree.c:751 rcu_read_unlock include/linux/rcupdate.h:879 [inline] class_rcu_destructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0x1a66/0x23c0 arch/x86/kernel/unwind_orc.c:695 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4501 [inline] slab_alloc_node mm/slub.c:4830 [inline] kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4837 alloc_empty_file+0x55/0x1d0 fs/file_table.c:237 path_openat+0x10f/0x3860 fs/namei.c:4816 do_file_open+0x23e/0x4a0 fs/namei.c:4859 do_sys_openat2+0x113/0x200 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1383 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f irq event stamp: 5590 hardirqs last enabled at (5589): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline] hardirqs last enabled at (5589): [] _raw_spin_unlock_irqrestore+0x30/0x80 kernel/locking/spinlock.c:194 hardirqs last disabled at (5588): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:130 [inline] hardirqs last disabled at (5588): [] _raw_spin_lock_irqsave+0x1a/0x60 kernel/locking/spinlock.c:162 softirqs last enabled at (5542): [] nr_release+0x20f/0x450 net/netrom/af_netrom.c:558 softirqs last disabled at (5590): [] spin_lock_bh include/linux/spinlock.h:347 [inline] softirqs last disabled at (5590): [] waveform_ao_cancel+0x8d/0x120 drivers/comedi/drivers/comedi_test.c:628 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&dev->spinlock); lock(&dev->spinlock); *** DEADLOCK *** 1 lock held by syz.6.5949/31470: #0: ffff888031eb18f8 (&dev->mutex#4){+.+.}-{4:4}, at: comedi_close+0x70/0x5e0 drivers/comedi/comedi_fops.c:3029 stack backtrace: CPU: 1 UID: 0 PID: 31470 Comm: syz.6.5949 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_usage_bug+0x28b/0x2e0 kernel/locking/lockdep.c:4042 valid_state kernel/locking/lockdep.c:4056 [inline] mark_lock_irq+0x410/0x420 kernel/locking/lockdep.c:-1 mark_lock+0x115/0x190 kernel/locking/lockdep.c:4753 mark_usage kernel/locking/lockdep.c:4662 [inline] __lock_acquire+0x9d0/0x2cf0 kernel/locking/lockdep.c:5191 lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:150 [inline] _raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:347 [inline] waveform_ao_cancel+0x8d/0x120 drivers/comedi/drivers/comedi_test.c:628 do_cancel drivers/comedi/comedi_fops.c:818 [inline] comedi_close+0x27e/0x5e0 drivers/comedi/comedi_fops.c:3036 __fput+0x44f/0xa70 fs/file_table.c:469 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x69b/0x2320 kernel/exit.c:971 __do_sys_exit kernel/exit.c:1079 [inline] __se_sys_exit kernel/exit.c:1077 [inline] __x64_sys_exit+0x40/0x40 kernel/exit.c:1077 x64_sys_call+0x2231/0x2240 arch/x86/include/generated/asm/syscalls_64.h:61 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f76f4b9c629 Code: Unable to access opcode bytes at 0x7f76f4b9c5ff. RSP: 002b:00007f76f5acafd8 EFLAGS: 00000246 ORIG_RAX: 000000000000003c RAX: ffffffffffffffda RBX: 00007f76f4e16090 RCX: 00007f76f4b9c629 RDX: 00007f76f5acb9c8 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f76f4c32b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f76f4e16128 R14: 00007f76f4e16090 R15: 00007ffe72fef4b8