[PATCH v3 00/14] KVM: PPC: Update Book3S HV memory handling

[Alexander Graf]

On 12.12.2011, at 23:23, 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
> 
> * Guests can be given read-only access to pages even though they think
>  they have mapped them read/write.  When they try to write to them
>  their access is upgraded to read/write.  This allows KSM to share
>  pages between guests.
> 
> 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 code is working well in my tests.  The sporadic crashes that I
> was seeing earlier are fixed by the second patch in the series.
> Somewhat to my surprise, when I implemented the last patch in the
> series I started to see KSM coalescing pages without any further
> effort on my part -- my tests were on a machine with Fedora 16
> installed, and it has ksmtuned running by default.
> 
> This series is on top of Alex Graf's kvm-ppc-next branch.  The first
> patch in my series fixes a bug in one of the patches in that branch
> ("KVM: PPC: booke: Improve timer register emulation").
> 
> These patches only touch arch/powerpc except for patch 12, which adds
> a couple of barriers to allow mmu_notifier_retry() to be used outside
> of the kvm->mmu_lock.

Thanks, applied all to kvm-ppc-next, awaiting the one follow-up patch though.


Alex