Subject: Re: Probing for native availability of isel from userspace

From: Benjamin Herrenschmidt <[email-masked]>
Date: Wed, 26 Sep 2012 06:59:31 +1000

On Tue, 2012-09-25 at 15:17 +0200, Segher Boessenkool wrote:
> >> Fine. But I believe that mfpvr emulation came first, which is the  
> >> point
> >> I object to (see the mess that the fact that CPUID is available to
> >> applications made to x86 when SSE registers were added).
> >
> > Heh, possibly, I don't remember... I added the cputable, I think we
> > added mfpvr because we didn't have anything, then I added cputable  
> > which
> > got us the HW caps, but some old stuff still relied on mfpvr so we
> > couldn't completely remove it.
> 
> If I have my history right end up, MFPVR emulation was added for MoL.
> Which is funny (if you like that kind of thing) because it now hurts
> all other "hypervisor in userspace" kind of things, that might want
> to lie in their emulated PVR...

Are you sure ? MOL had a kernel module, it wouldn't have needed that...

Cheers,
Ben.