comedi comedi3: c6xdigio: I/O port conflict (0x401,3)
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000007: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
CPU: 0 UID: 0 PID: 31763 Comm: syz.1.5479 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:kernfs_root+0x67/0x2a0 fs/kernfs/kernfs-internal.h:76
Code: 89 c6 e8 3c f4 57 ff 58 85 db 0f 85 b7 00 00 00 e8 ee f8 57 ff 48 8d 7d 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 1a 02 00 00 48 8b 5d 30 e8 66 92 fb 08 31 ff 41
RSP: 0018:ffffc9000bf7f910 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffc9000f8ca000
RDX: 0000000000000007 RSI: ffffffff826514b2 RDI: 0000000000000038
RBP: 0000000000000008 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffffffff8c1e6a80
R13: 0000000000000000 R14: 0000000000000000 R15: ffff88814c28a800
FS:  00007fd87f7c56c0(0000) GS:ffff888124a08000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fbfbff8 CR3: 0000000033fbd000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 kernfs_remove_by_name_ns+0x2e/0x110 fs/kernfs/dir.c:1711
 sysfs_remove_file include/linux/sysfs.h:770 [inline]
 driver_remove_file drivers/base/driver.c:201 [inline]
 driver_remove_file+0x4a/0x60 drivers/base/driver.c:197
 remove_bind_files drivers/base/bus.c:605 [inline]
 bus_remove_driver+0x224/0x2c0 drivers/base/bus.c:743
 driver_unregister+0x76/0xb0 drivers/base/driver.c:277
 comedi_device_detach_locked+0x12f/0xa50 drivers/comedi/drivers.c:207
 comedi_device_detach+0x67/0xb0 drivers/comedi/drivers.c:215
 comedi_device_attach+0x43d/0x900 drivers/comedi/drivers.c:1011
 do_devconfig_ioctl+0x1b1/0x710 drivers/comedi/comedi_fops.c:872
 comedi_unlocked_ioctl+0x165d/0x2f00 drivers/comedi/comedi_fops.c:2178
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd87e98f6c9
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:00007fd87f7c5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fd87ebe6180 RCX: 00007fd87e98f6c9
RDX: 0000200000000080 RSI: 0000000040946400 RDI: 000000000000000b
RBP: 00007fd87ea11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd87ebe6218 R14: 00007fd87ebe6180 R15: 00007fff868001d8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:kernfs_root+0x67/0x2a0 fs/kernfs/kernfs-internal.h:76
Code: 89 c6 e8 3c f4 57 ff 58 85 db 0f 85 b7 00 00 00 e8 ee f8 57 ff 48 8d 7d 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 1a 02 00 00 48 8b 5d 30 e8 66 92 fb 08 31 ff 41
RSP: 0018:ffffc9000bf7f910 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffc9000f8ca000
RDX: 0000000000000007 RSI: ffffffff826514b2 RDI: 0000000000000038
RBP: 0000000000000008 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffffffff8c1e6a80
R13: 0000000000000000 R14: 0000000000000000 R15: ffff88814c28a800
FS:  00007fd87f7c56c0(0000) GS:ffff888124a08000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fbfbff8 CR3: 0000000033fbd000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	89 c6                	mov    %eax,%esi
   2:	e8 3c f4 57 ff       	call   0xff57f443
   7:	58                   	pop    %rax
   8:	85 db                	test   %ebx,%ebx
   a:	0f 85 b7 00 00 00    	jne    0xc7
  10:	e8 ee f8 57 ff       	call   0xff57f903
  15:	48 8d 7d 30          	lea    0x30(%rbp),%rdi
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 1a 02 00 00    	jne    0x24e
  34:	48 8b 5d 30          	mov    0x30(%rbp),%rbx
  38:	e8 66 92 fb 08       	call   0x8fb92a3
  3d:	31 ff                	xor    %edi,%edi
  3f:	41                   	rex.B