Re: [RFC PATCH 0/11] KVM: PPC: Update Book3S HV memory handling

Alexander Graf
2011-11-18T13:57:11Z

On 16.11.2011, at 23:50, Paul Mackerras wrote:

> This series of patches updates the Book3S-HV KVM code that manages the
> guest hashed page table (HPT) to enable several things:
>
> * MMIO emulation and MMIO pass-through
>
> * Use of small pages (4kB or 64kB, depending on config) to back the
> guest memory
>
> * Pageable guest memory - i.e. backing pages can be removed from the
> guest and reinstated on demand, using the MMU notifier mechanism.
>
> On PPC970 we have no way to get DSIs and ISIs to come to the
> hypervisor, so we can't do MMIO emulation or pageable guest memory.
> On POWER7 we set the VPM1 bit in the LPCR to make all DSIs and ISIs
> come to the hypervisor (host) as HDSIs or HISIs.
>
> This series is RFC for the moment, although the first 5 or so patches
> are pretty solid and could go in. I am going to rework the later
> patches to use HPTEs with V=0 for the absent pages rather than key1,
> which will require handling the HPTE-not-present HDSIs we will get and
> differentiating the case where the guest has created a HPTE but the
> underlying page is not resident from the case where the guest has
> created no HPTE for the address.

This touches areas that I'm sure non-PPC people would want to see as well. Could you please CC kvm@vger too next time?

Avi, Marcelo, mind to review some of the bits in this patch set? :)

Alex