[moderation] [kernel?] BUG: workqueue leaked atomic, lock or RCU: ksoftirqd/NUM[NUM]

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 79e8447ec662 Merge tag 'phy-fix-6.17' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1013f642580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f5b21423ca3f0a96
dashboard link: https://syzkaller.appspot.com/bug?extid=ca8ee8ec1d2ab72a84cd
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
CC: [linux-...@vger.kernel.org pet...@infradead.org tg...@linutronix.de]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/39f45b6e753d/disk-79e8447e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6e166bdd6977/vmlinux-79e8447e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c1b0f02c2e73/bzImage-79e8447e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ca8ee8...@syzkaller.appspotmail.com

BUG: workqueue leaked atomic, lock or RCU: ksoftirqd/0[15]
preempt=0x00000000 lock=4->0 RCU=2->2 workfn=usb_giveback_urb_bh
INFO: lockdep is turned off.
CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0x11cb/0x17b0 kernel/workqueue.c:3319
bh_worker+0x2b1/0x600 kernel/workqueue.c:3579
tasklet_action+0xc/0x70 kernel/softirq.c:854
handle_softirqs+0x22f/0x710 kernel/softirq.c:579
run_ksoftirqd+0xac/0x210 kernel/softirq.c:968
smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:160
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>


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