comedi comedi1: c6xdigio: I/O port conflict (0x401,3) BUG: unable to handle page fault for address: ffffffff9ec04968 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD df3d067 P4D df3d067 PUD df3e063 PMD 0 Oops: Oops: 0000 [#1] SMP KASAN PTI CPU: 0 UID: 0 PID: 12487 Comm: syz.3.1880 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:222 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:233 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:__lock_acquire+0x6c1/0xd20 kernel/locking/lockdep.c:5207 Code: b3 00 00 00 4c 89 f6 ba 08 00 00 00 e8 88 25 00 00 45 31 ff 85 c0 0f 84 f5 05 00 00 83 3d d6 36 fe 17 00 75 13 48 63 44 24 20 <48> 0f a3 05 47 a7 fa 11 0f 83 15 05 00 00 31 ed 48 8b 3c 24 4c 8b RSP: 0018:ffffc90019be7810 EFLAGS: 00010046 RAX: 000000005940ad53 RBX: ffff88807c07bc80 RCX: ffffffff93439c08 RDX: 0000000000000008 RSI: ffff88807c07c828 RDI: ffff88807c07bc80 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8261a7cd R10: dffffc0000000000 R11: fffffbfff1f3cccf R12: 0000000000000004 R13: 0000000000000004 R14: ffff88807c07c828 R15: 0000000000000000 FS: 00007f17637496c0(0000) GS:ffff888125d18000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffff9ec04968 CR3: 000000006eb6c000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1590 kernfs_remove_by_name_ns+0x3d/0x130 fs/kernfs/dir.c:1712 remove_bind_files drivers/base/bus.c:605 [inline] bus_remove_driver+0x198/0x2f0 drivers/base/bus.c:743 comedi_device_detach_locked+0x178/0x750 drivers/comedi/drivers.c:207 comedi_device_detach drivers/comedi/drivers.c:215 [inline] comedi_device_attach+0x5d4/0x720 drivers/comedi/drivers.c:1011 do_devconfig_ioctl drivers/comedi/comedi_fops.c:872 [inline] comedi_unlocked_ioctl+0x5ff/0x1020 drivers/comedi/comedi_fops.c:2178 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f176298eec9 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:00007f1763749038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f1762be6180 RCX: 00007f176298eec9 RDX: 0000200000000080 RSI: 0000000040946400 RDI: 0000000000000004 RBP: 00007f1762a11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1762be6218 R14: 00007f1762be6180 R15: 00007ffdb9651b68 Modules linked in: CR2: ffffffff9ec04968 ---[ end trace 0000000000000000 ]--- RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:222 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:233 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:__lock_acquire+0x6c1/0xd20 kernel/locking/lockdep.c:5207 Code: b3 00 00 00 4c 89 f6 ba 08 00 00 00 e8 88 25 00 00 45 31 ff 85 c0 0f 84 f5 05 00 00 83 3d d6 36 fe 17 00 75 13 48 63 44 24 20 <48> 0f a3 05 47 a7 fa 11 0f 83 15 05 00 00 31 ed 48 8b 3c 24 4c 8b RSP: 0018:ffffc90019be7810 EFLAGS: 00010046 RAX: 000000005940ad53 RBX: ffff88807c07bc80 RCX: ffffffff93439c08 RDX: 0000000000000008 RSI: ffff88807c07c828 RDI: ffff88807c07bc80 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8261a7cd R10: dffffc0000000000 R11: fffffbfff1f3cccf R12: 0000000000000004 R13: 0000000000000004 R14: ffff88807c07c828 R15: 0000000000000000 FS: 00007f17637496c0(0000) GS:ffff888125d18000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffff9ec04968 CR3: 000000006eb6c000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: b3 00 mov $0x0,%bl 2: 00 00 add %al,(%rax) 4: 4c 89 f6 mov %r14,%rsi 7: ba 08 00 00 00 mov $0x8,%edx c: e8 88 25 00 00 call 0x2599 11: 45 31 ff xor %r15d,%r15d 14: 85 c0 test %eax,%eax 16: 0f 84 f5 05 00 00 je 0x611 1c: 83 3d d6 36 fe 17 00 cmpl $0x0,0x17fe36d6(%rip) # 0x17fe36f9 23: 75 13 jne 0x38 25: 48 63 44 24 20 movslq 0x20(%rsp),%rax * 2a: 48 0f a3 05 47 a7 fa bt %rax,0x11faa747(%rip) # 0x11faa779 <-- trapping instruction 31: 11 32: 0f 83 15 05 00 00 jae 0x54d 38: 31 ed xor %ebp,%ebp 3a: 48 8b 3c 24 mov (%rsp),%rdi 3e: 4c rex.WR 3f: 8b .byte 0x8b