[PATCH -V3 05/11] arch/powerpc: remove masking top 16 bit of va in tlb invalidate

[Paul Mackerras]

On Mon, Jul 23, 2012 at 11:22:08AM +1000, Benjamin Herrenschmidt wrote:
> On Mon, 2012-07-23 at 09:56 +1000, Paul Mackerras wrote:
> > > That indicate we should not mask the top 16 bits. So remove the
> > same.
> > 
> > Older versions of the architecture (2.02 and earler) require the
> > masking, so we can't just unconditionally remove it, since that would
> > potentially break POWER5 and PPC970.  People are definitely still
> > running Linux bare-metal on PPC970s (though arguably not on POWER5). 
> 
> Are you sure ? I couldn't convince myself ... the old architectures say
> that it only uses some of the bits but it doesn't mark the other ones as
> "reserved" (as in must be 0).
> 
> (At least 1.x, I haven't looked at 2.x with x < 03)

2.01 and 2.02 say bits 0..15 must be zero.

Paul.