[syzbot] [wireless?] WARNING in __alloc_workqueue

syzbot
2025-12-11T13:41:24Z

Hello,

syzbot found the following issue on:

HEAD commit: 37bb2e7217b0 Merge tag 'staging-6.19-rc1' of git://git.ker..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
console output: https://syzkaller.appspot.com/x/log.txt?x=125bceb4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e79f218bc0cd167b
dashboard link: https://syzkaller.appspot.com/bug?extid=392a2c3f461094707435
compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1046f21a580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12b9521a580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/26124775173b/disk-37bb2e72.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bd4182168b83/vmlinux-37bb2e72.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a78be0ee345d/bzImage-37bb2e72.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+392a2c3f461094707435@syzkaller.appspotmail.com

usb 3-1: SerialNumber: syz
usb 3-1: config 0 descriptor??
------------[ cut here ]------------
WARNING: kernel/workqueue.c:5701 at __alloc_workqueue+0x114c/0x1810 kernel/workqueue.c:5701, CPU#0: kworker/0:2/121
Modules linked in:
CPU: 0 UID: 0 PID: 121 Comm: kworker/0:2 Not tainted syzkaller #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:__alloc_workqueue+0x114c/0x1810 kernel/workqueue.c:5701
Code: e9 de fc ff ff 48 c7 44 24 08 e8 55 e8 88 e9 8f f6 ff ff 41 be 08 00 00 00 41 bd 00 04 00 00 e9 53 f1 ff ff e8 a5 9a 34 00 90 <0f> 0b 90 31 ed e9 af fc ff ff e8 95 9a 34 00 90 0f 0b 90 31 ed e9
RSP: 0018:ffffc900014aedf8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000002 RCX: ffffffff814b4179
RDX: ffff88810caa9d40 RSI: ffffffff814b527b RDI: 0000000000000005
RBP: ffffc900014aef60 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000002 R11: ffff88810caaa7e8 R12: 0000000000000003
R13: 0000000000000000 R14: ffffffff87e3cc20 R15: ffffc900014aeea0
FS: 0000000000000000(0000) GS:ffff888268bf5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8d89852a60 CR3: 0000000117746000 CR4: 00000000003506f0
Call Trace:
<TASK>
alloc_workqueue_noprof+0xd2/0x200 kernel/workqueue.c:5820
rtw_usb_init_rx drivers/net/wireless/realtek/rtw88/usb.c:968 [inline]
rtw_usb_probe+0x13bf/0x2d10 drivers/net/wireless/realtek/rtw88/usb.c:1295
usb_probe_interface+0x303/0xa80 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:581 [inline]
really_probe+0x241/0xb20 drivers/base/dd.c:659
__driver_probe_device+0x1de/0x470 drivers/base/dd.c:801
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
__device_attach_driver+0x1df/0x350 drivers/base/dd.c:959
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031
device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086
bus_probe_device+0x64/0x150 drivers/base/bus.c:574
device_add+0x116e/0x1980 drivers/base/core.c:3689
usb_set_configuration+0x1187/0x1e50 drivers/usb/core/message.c:2210
usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250
usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:581 [inline]
really_probe+0x241/0xb20 drivers/base/dd.c:659
__driver_probe_device+0x1de/0x470 drivers/base/dd.c:801
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
__device_attach_driver+0x1df/0x350 drivers/base/dd.c:959
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031
device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086
bus_probe_device+0x64/0x150 drivers/base/bus.c:574
device_add+0x116e/0x1980 drivers/base/core.c:3689
usb_new_device+0xd07/0x1a90 drivers/usb/core/hub.c:2695
hub_port_connect drivers/usb/core/hub.c:5567 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x31bf/0x5420 drivers/usb/core/hub.c:5953
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
</TASK>

---
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