[syzbot] [net?] [nfc?] WARNING in nci_rx_work

[syzbot <syzbot+0b9d9b42dd0539b0e9fe@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    1229e2e57a5c Merge tag 'v7.2-rc3-smb3-server-fixes' of git..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=170c5789580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=5c4196ba0e33631d
dashboard link: https://syzkaller.appspot.com/bug?extid=0b9d9b42dd0539b0e9fe
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e39c7e41c516/disk-1229e2e5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/cb6d56cd3388/vmlinux-1229e2e5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c229a44ba578/bzImage-1229e2e5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0b9d9b42dd0539b0e9fe@syzkaller.appspotmail.com

------------[ cut here ]------------
workqueue: cannot queue nci_cmd_work on wq nfc2_nci_cmd_wq
WARNING: kernel/workqueue.c:2306 at __queue_work+0xd4a/0x10a0 kernel/workqueue.c:2305, CPU#0: kworker/u8:4/75
Modules linked in:
CPU: 0 UID: 0 PID: 75 Comm: kworker/u8:4 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
Workqueue: nfc2_nci_rx_wq nci_rx_work
RIP: 0010:__queue_work+0xd66/0x10a0 kernel/workqueue.c:2305
Code: 49 81 c7 70 01 00 00 4c 8d 35 36 66 cd 0e 48 89 f8 48 c1 e8 03 80 3c 18 00 74 05 e8 c4 b8 a6 00 49 8b 75 18 4c 89 f7 4c 89 fa <67> 48 0f b9 3a 4c 89 e8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ef e8
RSP: 0018:ffffc900015e7998 EFLAGS: 00010046
RAX: 1ffff1100549d422 RBX: dffffc0000000000 RCX: 0000000000100000
RDX: ffff8880528c7970 RSI: ffffffff8ba1ec40 RDI: ffffffff905ab090
RBP: 0000000000000020 R08: ffff88802a4ea0ff R09: 1ffff1100549d41f
R10: dffffc0000000000 R11: ffffed100549d420 R12: 0000000000000008
R13: ffff88802a4ea0f8 R14: ffffffff905ab090 R15: ffff8880528c7970
FS:  0000000000000000(0000) GS:ffff888124f54000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b34012ff8 CR3: 00000000355ce000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 queue_work_on+0x106/0x1d0 kernel/workqueue.c:2452
 nci_rx_work+0x235/0x4b0 net/nfc/nci/core.c:1579
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
----------------
Code disassembly (best guess):
   0:	49 81 c7 70 01 00 00 	add    $0x170,%r15
   7:	4c 8d 35 36 66 cd 0e 	lea    0xecd6636(%rip),%r14        # 0xecd6644
   e:	48 89 f8             	mov    %rdi,%rax
  11:	48 c1 e8 03          	shr    $0x3,%rax
  15:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1)
  19:	74 05                	je     0x20
  1b:	e8 c4 b8 a6 00       	call   0xa6b8e4
  20:	49 8b 75 18          	mov    0x18(%r13),%rsi
  24:	4c 89 f7             	mov    %r14,%rdi
  27:	4c 89 fa             	mov    %r15,%rdx
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	4c 89 e8             	mov    %r13,%rax
  32:	48 c1 e8 03          	shr    $0x3,%rax
  36:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1)
  3a:	74 08                	je     0x44
  3c:	4c 89 ef             	mov    %r13,%rdi
  3f:	e8                   	.byte 0xe8


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