Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
CPU: 0 UID: 0 PID: 27473 Comm: syz.3.6568 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:pcl818_interrupt+0x80/0x9d0 drivers/comedi/drivers/pcl818.c:537
Code: 48 c1 e8 03 80 3c 08 00 74 12 4c 89 f7 e8 68 45 09 f9 48 b9 00 00 00 00 00 fc ff df 4d 8b 36 4d 8d 66 28 4d 89 e7 49 c1 ef 03 <41> 80 3c 0f 00 74 12 4c 89 e7 e8 41 45 09 f9 48 b9 00 00 00 00 00
RSP: 0018:ffffc90000007cc0 EFLAGS: 00010016
RAX: 1ffff11006255c3b RBX: ffff8880312ae000 RCX: dffffc0000000000
RDX: 0000000000010100 RSI: ffff8880312ae000 RDI: ffff8880312ae018
RBP: dffffc0000000000 R08: ffffffff90579137 R09: 1ffffffff20af226
R10: dffffc0000000000 R11: ffffffff892b5290 R12: 0000000000000028
R13: ffff888034decc80 R14: 0000000000000000 R15: 0000000000000005
FS:  00007f0a98f1e6c0(0000) GS:ffff888124f4e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33c23ffc CR3: 00000000511b8000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 __handle_irq_event_percpu+0x216/0x9a0 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+0x1f4/0x8a0 kernel/irq/chip.c:859
 generic_handle_irq_desc include/linux/irqdesc.h:188 [inline]
 handle_irq arch/x86/kernel/irq.c:209 [inline]
 call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
 __common_interrupt+0x141/0x1f0 arch/x86/kernel/irq.c:280
 common_interrupt+0x5e/0xe0 arch/x86/kernel/irq.c:273
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:665
RIP: 0010:variable_ffs arch/x86/include/asm/bitops.h:312 [inline]
RIP: 0010:handle_softirqs+0x15b/0x840 kernel/softirq.c:610
Code: 89 6c 24 20 0f b7 db 48 c7 c7 60 30 eb 8b e8 dc 80 48 0a 65 66 c7 05 ea 9d e4 11 00 00 e8 2d bc 46 00 fb 48 c7 c5 c0 a0 80 8e <b8> ff ff ff ff 0f bc c3 41 89 c4 41 ff c4 0f 84 09 04 00 00 89 5c
RSP: 0018:ffffc90000007f30 EFLAGS: 00000206
RAX: 0000000000000074 RBX: 0000000000000202 RCX: 0000000000000101
RDX: 0000000000000002 RSI: ffffffff8e22d06b RDI: ffffffff8c4bdc80
RBP: ffffffff8e80a0c0 R08: ffffffff90579137 R09: 1ffffffff20af226
R10: dffffc0000000000 R11: fffffbfff20af227 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888030f20000 R15: dffffc0000000000
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:198
Code: f7 e8 ad bc cf f5 f7 c3 00 02 00 00 74 05 e8 20 a1 fb f5 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> b4 d2 c0 f5 65 8b 05 ad 82 99 07 85 c0 74 18 5b 41 5e e9 7c a3
RSP: 0018:ffffc900032df840 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000283 RCX: 0000000080000001
RDX: 0000000000000006 RSI: ffffffff8e22d06b RDI: 0000000000000001
RBP: 0000000000000007 R08: ffffffff90579137 R09: 1ffffffff20af226
R10: dffffc0000000000 R11: fffffbfff20af227 R12: ffff88801c28a840
R13: ffff88801c28a800 R14: ffff88801c28a8a8 R15: dffffc0000000000
 __setup_irq+0xd53/0x2100 kernel/irq/manage.c:1806
 request_threaded_irq+0x2c1/0x3a0 kernel/irq/manage.c:2183
 request_irq include/linux/interrupt.h:176 [inline]
 pcl818_attach+0x261/0x1710 drivers/comedi/drivers/pcl818.c:1019
 comedi_device_attach+0x52d/0x720 drivers/comedi/drivers.c:1101
 do_devconfig_ioctl drivers/comedi/comedi_fops.c:930 [inline]
 comedi_unlocked_ioctl+0x8ef/0x1af0 drivers/comedi/comedi_fops.c:2302
 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+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0a97f9de99
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0a98f1e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f0a98225fa0 RCX: 00007f0a97f9de99
RDX: 0000200000000240 RSI: 0000000040946400 RDI: 0000000000000003
RBP: 00007f0a98033eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0a98226038 R14: 00007f0a98225fa0 R15: 00007ffcf1ccc0c8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:pcl818_interrupt+0x80/0x9d0 drivers/comedi/drivers/pcl818.c:537
Code: 48 c1 e8 03 80 3c 08 00 74 12 4c 89 f7 e8 68 45 09 f9 48 b9 00 00 00 00 00 fc ff df 4d 8b 36 4d 8d 66 28 4d 89 e7 49 c1 ef 03 <41> 80 3c 0f 00 74 12 4c 89 e7 e8 41 45 09 f9 48 b9 00 00 00 00 00
RSP: 0018:ffffc90000007cc0 EFLAGS: 00010016
RAX: 1ffff11006255c3b RBX: ffff8880312ae000 RCX: dffffc0000000000
RDX: 0000000000010100 RSI: ffff8880312ae000 RDI: ffff8880312ae018
RBP: dffffc0000000000 R08: ffffffff90579137 R09: 1ffffffff20af226
R10: dffffc0000000000 R11: ffffffff892b5290 R12: 0000000000000028
R13: ffff888034decc80 R14: 0000000000000000 R15: 0000000000000005
FS:  00007f0a98f1e6c0(0000) GS:ffff888124f4e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33c23ffc CR3: 00000000511b8000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	48 c1 e8 03          	shr    $0x3,%rax
   4:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1)
   8:	74 12                	je     0x1c
   a:	4c 89 f7             	mov    %r14,%rdi
   d:	e8 68 45 09 f9       	call   0xf909457a
  12:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  19:	fc ff df
  1c:	4d 8b 36             	mov    (%r14),%r14
  1f:	4d 8d 66 28          	lea    0x28(%r14),%r12
  23:	4d 89 e7             	mov    %r12,%r15
  26:	49 c1 ef 03          	shr    $0x3,%r15
* 2a:	41 80 3c 0f 00       	cmpb   $0x0,(%r15,%rcx,1) <-- trapping instruction
  2f:	74 12                	je     0x43
  31:	4c 89 e7             	mov    %r12,%rdi
  34:	e8 41 45 09 f9       	call   0xf909457a
  39:	48                   	rex.W
  3a:	b9 00 00 00 00       	mov    $0x0,%ecx