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

[syzbot]

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+0b9d9b...@syzkaller.appspotmail.com

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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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