Subject: Re: [PATCH V2 26/68] powerpc/mm/radix: Add radix pte defines

From: Benjamin Herrenschmidt <[email-masked]>
Date: Sat, 23 Apr 2016 18:30:19 +1000

On Thu, 2016-04-21 at 14:12 +1000, Balbir Singh wrote:
> > +     } while (cpu_to_be64(old_pte) != __cmpxchg_u64((unsigned long *)ptep,
> > +                                                    cpu_to_be64(old_pte),
> > +                                                    cpu_to_be64(new_pte)));
> > +     /* We already do a sync in cmpxchg, is ptesync needed ?*/
> > +     asm volatile("ptesync" : : : "memory");
> 
> Yes, I think ptesync is required after PTE changes

Is it really on radix ? I'm not 100% sure... it's usually needed to
synchronize the writebacks of R and C...

Cheers,
Ben.