> > > + * Some machines get here with interrupts disabled. The same arch
> > > + * code path leads to calling into get_signal_to_deliver(), which
> > > + * implicitly reenables them by virtue of spin_unlock_irq.
> > > + */
> > > + local_irq_enable();
> >
> > Hrmm, I would much prefer to fix up the calling conventions of
> > tracehook_notify_resume() than to bury something like this in the guts
> > of a tracehook user.
The reason I did it this way was mainly just not to make the requirement
for arch maintainers' too subtle. As it is, we just say that you call
tracehook_notify_resume() after clearing TIF_NOTIFY_RESUME, when it was
set. That keeps the specification quite simple. Of course, that is not
really much of a reason. If arch folks don't mind the requirement to
replace e.g.:
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
}
with:
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
local_irq_enable();
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
}
then that is certainly fine by me. But we do now have almost all the
arch's calling tracehook_notify_resume() and I don't know how many of
them do it in irqs-disabled context so they would need this change.
> But in any case, imho it would be better to do this after we merge utrace,
> otherwise we need more subtle arch-dependent changes before.
I tend to agree.
Thanks,
Roland
