Re: [syzbot] [kernel?] INFO: task hung in nsim_bus_dev_del

From: Hillf Danton

Date: Sat May 16 2026 - 07:04:54 EST


> Date: Fri, 15 May 2026 17:11:33 -0700 [thread overview]
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 5cbb61bf4168 arm64/fpsimd: ptrace: zero target's fpsimd_st..
> git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
> console output: https://syzkaller.appspot.com/x/log.txt?x=165db76c580000
> kernel config: https://syzkaller.appspot.com/x/.config?x=a834c6344141a58b
> dashboard link: https://syzkaller.appspot.com/bug?extid=1cf303af03cf30b1275a
> compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
> userspace arch: arm64
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12c4d56a580000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=115db76c580000

#syz test

--- x/kernel/workqueue.c
+++ y/kernel/workqueue.c
@@ -2384,6 +2384,10 @@ retry:
work_flags |= WORK_STRUCT_INACTIVE;
insert_work(pwq, work, &pwq->inactive_works, work_flags);
}
+ do {
+ unsigned long data = *work_data_bits(work);
+ BUG_ON(data & WORK_OFFQ_DISABLE_MASK);
+ } while (0);

out:
raw_spin_unlock(&pool->lock);
--