floppy1: FDC access conflict!
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 2 PID: 9 Comm: kworker/u16:0 Not tainted 6.1.0-rc8-syzkaller-17162-g8ed710da2873 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: floppy floppy_work_workfn
RIP: 0010:start_motor+0x3a/0x3f0 drivers/block/floppy.c:1905
Code: 08 e8 9a 1f 88 fc 48 8b 1d 53 a3 d3 0c 48 b8 00 00 00 00 00 fc ff df 0f b6 2d a2 8d d3 0c 48 89 da 48 c1 ea 03 89 e9 41 89 ed <0f> b6 04 02 83 e1 03 41 83 e5 03 84 c0 74 08 3c 03 0f 8e be 02 00
RSP: 0018:ffffc900005cfc98 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff84f72106 RDI: ffffffff84f73ae0
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff84f73ae0
R13: 0000000000000001 R14: ffff88804030b400 R15: ffff888012071800
FS:  0000000000000000(0000) GS:ffff88802c800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7eaa84b718 CR3: 0000000000743000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 floppy_ready+0x87/0x1940 drivers/block/floppy.c:1932
 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289
 worker_thread+0x669/0x1090 kernel/workqueue.c:2436
 kthread+0x2e8/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:start_motor+0x3a/0x3f0 drivers/block/floppy.c:1905
Code: 08 e8 9a 1f 88 fc 48 8b 1d 53 a3 d3 0c 48 b8 00 00 00 00 00 fc ff df 0f b6 2d a2 8d d3 0c 48 89 da 48 c1 ea 03 89 e9 41 89 ed <0f> b6 04 02 83 e1 03 41 83 e5 03 84 c0 74 08 3c 03 0f 8e be 02 00
RSP: 0018:ffffc900005cfc98 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff84f72106 RDI: ffffffff84f73ae0
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff84f73ae0
R13: 0000000000000001 R14: ffff88804030b400 R15: ffff888012071800
FS:  0000000000000000(0000) GS:ffff88802c900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555571c7708 CR3: 000000001ef5c000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	e8 9a 1f 88 fc       	callq  0xfc881f9f
   5:	48 8b 1d 53 a3 d3 0c 	mov    0xcd3a353(%rip),%rbx        # 0xcd3a35f
   c:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  13:	fc ff df
  16:	0f b6 2d a2 8d d3 0c 	movzbl 0xcd38da2(%rip),%ebp        # 0xcd38dbf
  1d:	48 89 da             	mov    %rbx,%rdx
  20:	48 c1 ea 03          	shr    $0x3,%rdx
  24:	89 e9                	mov    %ebp,%ecx
  26:	41 89 ed             	mov    %ebp,%r13d
* 29:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax <-- trapping instruction
  2d:	83 e1 03             	and    $0x3,%ecx
  30:	41 83 e5 03          	and    $0x3,%r13d
  34:	84 c0                	test   %al,%al
  36:	74 08                	je     0x40
  38:	3c 03                	cmp    $0x3,%al
  3a:	0f                   	.byte 0xf
  3b:	8e                   	.byte 0x8e
  3c:	be                   	.byte 0xbe
  3d:	02 00                	add    (%rax),%al