Re: [syzbot] [wireguard?] WARNING in kthread_unpark (2)

[Hillf Danton]

On Mon, 29 Jul 2024 08:48:30 -0700
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    dc1c8034e31b minmax: simplify min()/max()/clamp() implemen..
> git tree:       upstream
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1022b573980000

#syz test upstream  dc1c8034e31b

--- x/kernel/workqueue.c
+++ y/kernel/workqueue.c
@@ -2679,7 +2679,8 @@ static void worker_attach_to_pool(struct
 		worker->flags |= WORKER_UNBOUND;
 	} else {
 		WARN_ON_ONCE(pool->flags & POOL_BH);
-		kthread_set_per_cpu(worker->task, pool->cpu);
+		if (!worker->rescue_wq)
+			kthread_set_per_cpu(worker->task, pool->cpu);
 	}
 
 	if (worker->rescue_wq)
--