Re: [PATCH] kernel/signal.c: Export symbol __lock_task_sighand

[Oleg Nesterov]

On 06/22, Christian Brauner wrote:
>
> It is a supported case however unlikely. I just tried to answer
> Dominique's specific question pointing out that even in that unlikely
> case sighand_struct is stable.

I too tried to say this, but apparently just added more confusion ;)

> Just as an fyi, CLONE_SIGHAND with CLONE_VM but without CLONE_THREAD is
> actually used quite a bit, e.g. in newlib, in stress-ng, and in criu.

OK,

> you'd want CLONE_VM which enforces
> CLONE_SIGHAND so that would be another use-case afaict.

Cough no ;) CLONE_SIGHAND requires CLONE_VM, not vice versa.

> > But this doesn't really matter. I mean, even if you race with another
> > thread doing exec/exit/whatever, current->sighand is stable. Unless, again,
> > current has already exited (called exit_notify()).

Oleg.