Re: [PATCH v3 3/4] powerpc/64: make buildable without CONFIG_COMPAT

[Christophe Leroy]

Le 29/08/2019 Ã 10:01, Arnd Bergmann a ÃcritÂ:
> On Thu, Aug 29, 2019 at 8:46 AM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote:
>
> > > @@ -277,7 +277,7 @@ static void do_signal(struct task_struct *tsk)
> > >
> > >        rseq_signal_deliver(&ksig, tsk->thread.regs);
> > >
> > > -     if (is32) {
> > > +     if ((IS_ENABLED(CONFIG_PPC32) || IS_ENABLED(CONFIG_COMPAT)) && is32) {
> >
> > I think we should fix the is_32bit_task definitions instead so that
> > callers don't need this mess.  I'd suggest something like:
> >
> > #ifdef CONFIG_COMPAT
> > #define is_32bit_task()         test_thread_flag(TIF_32BIT)
> > #else
> > #define is_32bit_task()         IS_ENABLED(CONFIG_PPC32)
> > #endif
>
> Are there actually any (correct) uses of is_32bit_task() outside of
> #ifdef CONFIG_PPC64?

There is at least  stack_maxrandom_size()
Also  brk_rnd() and do_signal()

Christophe

> I suspect most if not all could be changed to the generic
> in_compat_syscall() that we use outside of architecture specific
> code.
>
>         Arnd