[PATCH v6 0/7] Enlightened VMCS support for KVM on Hyper-V

[Vitaly Kuznetsov <vkuznets@redhat.com>]

Changes since v5:
- Fix a couple of issues reported by kbuild test robot, both in
  PATCH7 (hope Radim's Reviewed-by: stands).

When running nested KVM on Hyper-V it's possible to use so called
'Enlightened VMCS' and do normal memory reads/writes instead of
doing VMWRITE/VMREAD instructions. In addition, clean field mask
provides a huge room for optimization on L0's side.

Tight CPUID loop test shows significant speedup (E5-2667 v4 @ 3.20GHz):
  Before: 18890 cycles
  After: 8304 cycles

Ladi Prosek (1):
  x86/kvm: rename HV_X64_MSR_APIC_ASSIST_PAGE to
    HV_X64_MSR_VP_ASSIST_PAGE

Vitaly Kuznetsov (6):
  x86/hyper-v: move hyperv.h out of uapi
  x86/hyper-v: move definitions from TLFS to hyperv-tlfs.h
  x86/hyper-v: allocate and use Virtual Processor Assist Pages
  x86/hyper-v: define struct hv_enlightened_vmcs and clean field bits
  x86/hyper-v: detect nested features
  x86/kvm: use Enlightened VMCS when running on Hyper-V

 MAINTAINERS                                        |   2 +-
 arch/x86/hyperv/hv_init.c                          |  45 ++-
 .../{uapi/asm/hyperv.h => asm/hyperv-tlfs.h}       | 295 ++++++++++++++++++-
 arch/x86/include/asm/kvm_host.h                    |   1 +
 arch/x86/include/asm/mshyperv.h                    |  94 +-----
 arch/x86/include/uapi/asm/kvm_para.h               |   1 -
 arch/x86/kernel/cpu/mshyperv.c                     |  22 +-
 arch/x86/kvm/hyperv.c                              |   8 +-
 arch/x86/kvm/lapic.h                               |   2 +-
 arch/x86/kvm/vmx.c                                 | 301 ++++++++++++++++++-
 arch/x86/kvm/vmx_evmcs.h                           | 324 +++++++++++++++++++++
 arch/x86/kvm/x86.c                                 |   2 +-
 drivers/hv/connection.c                            |   1 -
 drivers/hv/hv.c                                    |   1 -
 drivers/hv/hyperv_vmbus.h                          |   1 +
 drivers/hv/vmbus_drv.c                             |   1 -
 include/linux/hyperv.h                             |   1 -
 17 files changed, 983 insertions(+), 119 deletions(-)
 rename arch/x86/include/{uapi/asm/hyperv.h => asm/hyperv-tlfs.h} (65%)
 create mode 100644 arch/x86/kvm/vmx_evmcs.h

-- 
2.14.3