Re: [PATCH] kvm/ppc/booke64: fix build breakage from Altivec, and disable e6500

[Scott Wood <scottwood@freescale.com>]

On 05/10/2013 04:40:01 AM, Caraman Mihai Claudiu-B02008 wrote:
> > -----Original Message-----
> > From: Wood Scott-B07421
> > Sent: Friday, May 10, 2013 6:15 AM
> > To: Alexander Graf
> > Cc: kvm-ppc@vger.kernel.org; kvm@vger.kernel.org; Wood Scott-B07421;
> > Caraman Mihai Claudiu-B02008
> > Subject: [PATCH] kvm/ppc/booke64: fix build breakage from Altivec,  
> and
> > disable e6500
> >
> > BookE altivec support brought two new exceptions, but KVM was not
> > updated, so the build broke for all 64-bit booke with KVM enabled.
> 
> We couldn't do that in KVM before having  
> BOOKE_INTERRUPT_ALTIVEC_UNAVAIL/
> BOOKE_INTERRUPT_ALTIVEC_ASSIST. As Tiejun noticed earlier we should  
> have
> done this in Kumar's tree but we missed that chance. We will face  
> similar
> issues every time an exception handler will be added.

Exceptions don't get handled all that often, and ideally we catch it  
when it's added rather than after-the-fact.

> > diff --git a/arch/powerpc/kvm/bookehv_interrupts.S
> > b/arch/powerpc/kvm/bookehv_interrupts.S
> > index e8ed7d6..6397613 100644
> > --- a/arch/powerpc/kvm/bookehv_interrupts.S
> > +++ b/arch/powerpc/kvm/bookehv_interrupts.S
> > @@ -309,6 +309,10 @@ kvm_handler BOOKE_INTERRUPT_DOORBELL_CRITICAL,
> > EX_PARAMS(CRIT), \
> >  	SPRN_CSRR0, SPRN_CSRR1, 0
> >  kvm_handler BOOKE_INTERRUPT_HV_PRIV, EX_PARAMS(GEN), \
> >  	SPRN_SRR0, SPRN_SRR1, NEED_EMU
> > +kvm_handler BOOKE_INTERRUPT_ALTIVEC_UNAVAIL, EX_PARAMS(GEN), \
> > +	SPRN_SRR0, SPRN_SRR1, 0
> > +kvm_handler BOOKE_INTERRUPT_ALTIVEC_ASSIST, EX_PARAMS(GEN), \
> > +	SPRN_SRR0, SPRN_SRR1, 0
> 
> Why not NEED_ESR as we did in our SDK?

This is just to fix the build break -- we don't need ESR yet.  Though I  
did look at the ESR documentation and didn't see where Altivec  
exceptions used it (I do see a couple places now).

-Scott