[PATCH v5 00/10] Nested VMX: Add virtual EPT & VPID support to L1 VMM

[Xiantao Zhang <xiantao.zhang@intel.com>]

From: Zhang Xiantao <xiantao.zhang@intel.com>

With virtual EPT support, L1 hyerpvisor can use EPT hardware for L2 guest's memory virtualization.
In this way, L2 guest's performance can be improved sharply.
According to our testing, some benchmarks can show > 5x performance gain.

Changes from v1:
Update the patches according to Tim's comments.
1. Patch 03: Enhance the virtual EPT's walker logic.
2. Patch 04: Add a new field in struct p2m_domain, and use it to store
   EPT-specific data. For host p2m, it saves L1 VMM's EPT data,
   and for nested p2m, it saves nested EPT's data 3. Patch 07: strictly check host's p2m access type.
4. Other patches: some whitespace mangling fixes.

Changes form v2:
Addressed comments from Jan and Jun:
1. Add Acked-by message for reviewed patches by Tim.
2. Fixed one whitespace mangling issue in PATCH 08 3. Add some comments to describe the meaning of
   the return value of hvm_hap_nested_page_fault
   in PATCH 05.
4. Add the logic for handling default case of two switch
   statements.

Changes from v3:
1. Re-check all patches' whitespace mangling issue.

2. Addressed Jan's comments in Patch08 and Patch09 that once return X86EMUL_EXCEPTION, the callee
should be responsible for handling the execption before its return.

3. Addressed Tim's comments in Patch03 and Patch04 and Patch07:
   Patch03: If host doesn't support exec-only capability, we shoudln't expost this feature to L1 VMM.
            Once map guest's EPT table error, inject an EPT misconfiguration errot to L1.
   Patch04: Re-organize p2m's and nested p2m's structure {init/teardown} logic.
   Patch07: Initialize p2ma_21  -> p2m_access_rwx, so not to change SVM's behavior.

Changes from v4:
   Patch08/09: Minor changes according to Jan's comments.


Zhang Xiantao (10):
  nestedhap: Change hostcr3 and p2m->cr3 to meaningful words
  nestedhap: Change nested p2m's walker to vendor-specific
  nested_ept: Implement guest ept's walker
  EPT: Make ept data structure or operations neutral
  nEPT: Try to enable EPT paging for L2 guest.
  nEPT: Sync PDPTR fields if L2 guest in PAE paging mode
  nEPT: Use minimal permission for nested p2m.
  nEPT: handle invept instruction from L1 VMM
  nVMX: virutalize VPID capability to nested VMM.
  nEPT: Expose EPT & VPID capablities to L1 VMM

 xen/arch/x86/hvm/hvm.c                  |    7 +-
 xen/arch/x86/hvm/svm/nestedsvm.c        |   31 ++++
 xen/arch/x86/hvm/svm/svm.c              |    3 +-
 xen/arch/x86/hvm/vmx/vmcs.c             |    8 +-
 xen/arch/x86/hvm/vmx/vmx.c              |   97 ++++------
 xen/arch/x86/hvm/vmx/vvmx.c             |  205 ++++++++++++++++++++--
 xen/arch/x86/mm/guest_walk.c            |   16 +-
 xen/arch/x86/mm/hap/Makefile            |    1 +
 xen/arch/x86/mm/hap/nested_ept.c        |  298 +++++++++++++++++++++++++++++++
 xen/arch/x86/mm/hap/nested_hap.c        |   96 ++++++-----
 xen/arch/x86/mm/mm-locks.h              |    2 +-
 xen/arch/x86/mm/p2m-ept.c               |  104 +++++++++---
 xen/arch/x86/mm/p2m.c                   |  158 +++++++++++------
 xen/include/asm-x86/guest_pt.h          |    8 +
 xen/include/asm-x86/hvm/hvm.h           |    9 +-
 xen/include/asm-x86/hvm/nestedhvm.h     |    1 +
 xen/include/asm-x86/hvm/svm/nestedsvm.h |    3 +
 xen/include/asm-x86/hvm/vmx/vmcs.h      |   24 ++--
 xen/include/asm-x86/hvm/vmx/vmx.h       |   41 ++++-
 xen/include/asm-x86/hvm/vmx/vvmx.h      |   30 +++-
 xen/include/asm-x86/p2m.h               |   20 ++-
 21 files changed, 937 insertions(+), 225 deletions(-)
 create mode 100644 xen/arch/x86/mm/hap/nested_ept.c