Re: [PATCH 1/2] exec: don't wait for zombie threads with cred_guard_mutex held

From: Oleg Nesterov
Date: Mon Feb 13 2017 - 13:01:43 EST


On 02/13, Mika Penttilä wrote:
>
> > +int de_thread(struct task_struct *tsk)
> > {
> > struct signal_struct *sig = tsk->signal;
> > struct sighand_struct *oldsighand = tsk->sighand;
> > @@ -1051,60 +1100,24 @@ static int de_thread(struct task_struct *tsk)
> > if (thread_group_empty(tsk))
> > goto no_thread_group;
> >
> > - /*
> > - * Kill all other threads in the thread group.
> > - */
> > spin_lock_irq(lock);
> > - if (signal_group_exit(sig)) {
> > - /*
> > - * Another group action in progress, just
> > - * return so that the signal is processed.
> > - */
> > - spin_unlock_irq(lock);
> > - return -EAGAIN;
> > - }
> > -
> > - sig->group_exit_task = tsk;
> > - sig->notify_count = zap_other_threads(tsk);
> > + sig->notify_count = sig->nr_threads;
>
>
> maybe nr_threads - 1 since nr_threads includes us ?

Damn. Of course you are right, thanks a lot! Please see v2.

Hmm. I didn't even notice my own test-case didn't pass because of this
off-by-one.

Oleg.