On Wed, Aug 03, 2016 at 06:40:53PM +1000, Alexey Kardashevskiy wrote: > It does not make much sense to have KVM in book3s-64 and > not to have IOMMU bits for PCI pass through support as it costs little > and allows VFIO to function on book3s KVM. > > Having IOMMU_API always enabled makes it unnecessary to have a lot of > "#ifdef IOMMU_API" in arch/powerpc/kvm/book3s_64_vio*. With those > ifdef's we could have only user space emulated devices accelerated > (but not VFIO) which do not seem to be very useful. > > Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru> > --- > arch/powerpc/kvm/Kconfig | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig > index b7c494b..63b60a8 100644 > --- a/arch/powerpc/kvm/Kconfig > +++ b/arch/powerpc/kvm/Kconfig > @@ -65,6 +65,7 @@ config KVM_BOOK3S_64 > select KVM > select KVM_BOOK3S_PR_POSSIBLE if !KVM_BOOK3S_HV_POSSIBLE > select KVM_VFIO if VFIO > + select SPAPR_TCE_IOMMU if IOMMU_SUPPORT > ---help--- > Support running unmodified book3s_64 and book3s_32 guest kernels > in virtual machines on book3s_64 host processors.
I don't quite see how this change accomplishes the stated goal.
AFAICT even with this change you can still turn off IOMMU_SUPPORT,
which will break the IOMMU for VFIO passthrough, but not IOMMU
acceleration for emulated devices (since that requires no interaction
with the hardware IOMMU).
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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