[PATCH 0/9] Add support for nested SVM (kernel) v5

[Alexander Graf <agraf@suse.de>]

The current generation of virtualization extensions only supports one VM layer.
While we can't change that, it is pretty easy to emulate the CPU's behavior
and implement the virtualization opcodes ourselves.

This patchset does exactly this for SVM. Using it, KVM can run within a VM.
Since we're emulating the real CPU's behavior, this should also enable other
VMMs to run within KVM.
So far I've only tested to run KVM inside the VM though.

As always, comments and suggestions are highly welcome.

v2 takes most comments from Avi into account.

v3 addresses Joergs comments, including

- V_INTR_MASKING support
- a generic permission checking helper

v4 addresses even more comments from Joerg, including

- don't use the guest's hsave to store the guest's vmcb in
- add nested=<int> flag for kvm-amd.ko, defaults to 0 (off)
- include Joerg's VM_CR MSR patch

v5 removes the IOPM merging code

To be usable, this patchset requires the two simple changes in the userspace
part, that I sent to the list with the first version.

Known issues:

- TODO: #VMEXIT on save/restore
- SMP l2 guests break with in-kernel-apic

Thanks for reviewing!

Alex


Alexander Graf (8):
  Clean up VINTR setting v5
  Add helper functions for nested SVM v5
  Implement GIF, clgi and stgi v5
  Implement hsave v5
  Add VMLOAD and VMSAVE handlers v5
  Add VMRUN handler v5
  Add VMEXIT handler and intercepts v5
  Allow setting the SVME bit v5

Joerg Roedel (1):
  allow read access to MSR_VM_VR

 arch/x86/kvm/kvm_svm.h     |    9 +
 arch/x86/kvm/svm.c         |  682 +++++++++++++++++++++++++++++++++++++++++++-
 include/asm-x86/kvm_host.h |    5 +
 3 files changed, 684 insertions(+), 12 deletions(-)