[RFC PATCH 2/3] exec: don't wait for zombie threads with cred_guard_mutex held

[Cyrill Gorcunov]

On Sun, Nov 09, 2025 at 06:15:33PM +0100, Oleg Nesterov wrote:
..
> static int kill_sub_threads(struct task_struct *tsk)
> {
>  	struct signal_struct *sig = tsk->signal;
> 	int err = -EINTR;
> 
> 	read_lock(&tasklist_lock);
> 	spin_lock_irq(&tsk->sighand->siglock);
> 	if (!((sig->flags & SIGNAL_GROUP_EXIT) || sig->group_exec_task)) {
> 		sig->group_exec_task = tsk;
> 		sig->notify_count = -zap_other_threads(tsk);

Hi Oleg! I somehow manage to miss a moment -- why negative result here?

> 		err = 0;
> 	}
> 	spin_unlock_irq(&tsk->sighand->siglock);
> 	read_unlock(&tasklist_lock);
> 
> 	return err;
> }

p.s. i've dropped long CC but left ML intact)

	Cyrill