Re: [PATCH v3 20/20] signal: Don't restart fork when signals come in.

[Oleg Nesterov]

On 07/24, Eric W. Biederman wrote:
>
> Similarly the current code will also miss blocked
> signals that are delivered to multiple process, as those signals will
> not appear pending during fork.

Well, I still think this needs a separate change and discussion...

Let me repeat, I simply do not know if this is good or not, I don't know
if the current behaviour is by design or it is mistake.

OK, I won't argue but note that your patch doesn't really fix the problem,

> +     spin_lock_irq(&current->sighand->siglock);
> +     if (!(clone_flags & CLONE_THREAD))
> +             hlist_add_head(&delayed.node, &current->signal->multiprocess);
> +     recalc_sigpending();
> +     spin_unlock_irq(&current->sighand->siglock);
> +     retval = -ERESTARTNOINTR;
> +     if (signal_pending(current))
> +             goto fork_out;

because recalc_sigpending() will not notice the blocked multiprocess signal
if it is already pending.

Oleg.