On Mon, Jul 08, 2024 at 04:40:07PM +0100, Pavel Begunkov wrote:
> > > --- a/kernel/signal.c
> > > +++ b/kernel/signal.c
> > > @@ -2694,6 +2694,10 @@ bool get_signal(struct ksignal *ksig)
> > > try_to_freeze();
> > > relock:
> > > + clear_notify_signal();
> > > + if (unlikely(task_work_pending(current)))
> > > + task_work_run();
> > > +
> > > spin_lock_irq(&sighand->siglock);
> >
> > Well, but can't we kill the same code at the start of get_signal() then?
> > Of course, in this case get_signal() should check signal_pending(), not
> > task_sigpending().
>
> Should be fine, but I didn't want to change the
> try_to_freeze() -> __refrigerator() path, which also reschedules.
>
> > Or perhaps something like the patch below makes more sense? I dunno...
>
> It needs a far backporting, I'd really prefer to keep it
> lean and without more side effects if possible, unless
> there is a strong opinion on that.
It's been a minute since I dug my way through the signal code, but I
think I slightly favour Oleg's version for not duplicating that
task_work_run().
> > diff --git a/kernel/signal.c b/kernel/signal.c
> > index 1f9dd41c04be..e2ae85293fbb 100644
> > --- a/kernel/signal.c
> > +++ b/kernel/signal.c
> > @@ -2676,6 +2676,7 @@ bool get_signal(struct ksignal *ksig)
> > struct signal_struct *signal = current->signal;
> > int signr;
> > +start:
> > clear_notify_signal();
> > if (unlikely(task_work_pending(current)))
> > task_work_run();
> > @@ -2760,10 +2761,11 @@ bool get_signal(struct ksignal *ksig)
> > if (current->jobctl & JOBCTL_TRAP_MASK) {
> > do_jobctl_trap();
> > spin_unlock_irq(&sighand->siglock);
> > + goto relock;
> > } else if (current->jobctl & JOBCTL_TRAP_FREEZE)
> > do_freezer_trap();
> > -
> > - goto relock;
> > + goto start;
> > + }
> > }
> > /*
> >
>
> --
> Pavel Begunkov
