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comedi comedi1: c6xdigio: I/O port conflict (0x401,3)
BUG: unable to handle page fault for address: ffffffff9e7874e8
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD db3b067 P4D db3b067 PUD db3c063 PMD 0 
Oops: Oops: 0000 [#1] SMP KASAN NOPTI
CPU: 1 UID: 0 PID: 24495 Comm: syz.0.3761 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:227 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:239 [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 b6 b8 b7 17 00 75 13 48 63 44 24 20 <48> 0f a3 05 27 29 b4 11 0f 83 15 05 00 00 31 ed 48 8b 3c 24 4c 8b
RSP: 0018:ffffc9000cf87830 EFLAGS: 00010046
RAX: 0000000059410953 RBX: ffff88808032bc80 RCX: ffffffff92f89c08
RDX: 0000000000000008 RSI: ffff88808032c828 RDI: ffff88808032bc80
RBP: 0000000000000000 R08: ffffc9000cf87770 R09: 0000000000000030
R10: 000000006ebc5405 R11: ffffffff819c6130 R12: 0000000000000004
R13: 0000000000000003 R14: ffff88808032c828 R15: 0000000000000000
FS:  00007fc43eb526c0(0000) GS:ffff888126496000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff9e7874e8 CR3: 0000000065e1d000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 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/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc43dd8eec9
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:00007fc43eb52038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fc43dfe5fa0 RCX: 00007fc43dd8eec9
RDX: 0000200000000080 RSI: 0000000040946400 RDI: 0000000000000003
RBP: 00007fc43de11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc43dfe6038 R14: 00007fc43dfe5fa0 R15: 00007fff82c6b278
 </TASK>
Modules linked in:
CR2: ffffffff9e7874e8
---[ end trace 0000000000000000 ]---
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:227 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:239 [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 b6 b8 b7 17 00 75 13 48 63 44 24 20 <48> 0f a3 05 27 29 b4 11 0f 83 15 05 00 00 31 ed 48 8b 3c 24 4c 8b
RSP: 0018:ffffc9000cf87830 EFLAGS: 00010046
RAX: 0000000059410953 RBX: ffff88808032bc80 RCX: ffffffff92f89c08
RDX: 0000000000000008 RSI: ffff88808032c828 RDI: ffff88808032bc80
RBP: 0000000000000000 R08: ffffc9000cf87770 R09: 0000000000000030
R10: 000000006ebc5405 R11: ffffffff819c6130 R12: 0000000000000004
R13: 0000000000000003 R14: ffff88808032c828 R15: 0000000000000000
FS:  00007fc43eb526c0(0000) GS:ffff888126496000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff9e7874e8 CR3: 0000000065e1d000 CR4: 0000000000350ef0
----------------
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 b6 b8 b7 17 00 	cmpl   $0x0,0x17b7b8b6(%rip)        # 0x17b7b8d9
  23:	75 13                	jne    0x38
  25:	48 63 44 24 20       	movslq 0x20(%rsp),%rax
* 2a:	48 0f a3 05 27 29 b4 	bt     %rax,0x11b42927(%rip)        # 0x11b42959 <-- 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