Changes in v3:
*Add comments for patch that disable PKU feature without ept.

Changes in v2:
*Add pku.c for kvm-unit-tests.
*Optimize permission_fault codes for patch4.
*Delete is_long_mode and PK for patch5.
*Squash cpuid and cr4 patches.

The protection-key feature provides an additional mechanism by which IA-32e
paging controls access to usermode addresses.

Hardware support for protection keys for user pages is enumerated with CPUID
feature flag CPUID.7.0.ECX[3]:PKU. Software support is CPUID.7.0.ECX[4]:OSPKE
with the setting of CR4.PKE(bit 22).

When CR4.PKE = 1, every linear address is associated with the 4-bit protection
key located in bits 62:59 of the paging-structure entry that mapped the page
containing the linear address. The PKRU register determines, for each
protection key, whether user-mode addresses with that protection key may be
read or written.

The PKRU register (protection key rights for user pages) is a 32-bit register
with the following format: for each i (0 ≤ i ≤ 15), PKRU[2i] is the
access-disable bit for protection key i (ADi); PKRU[2i+1] is the write-disable
bit for protection key i (WDi).

Software can use the RDPKRU and WRPKRU instructions with ECX = 0 to read and
write PKRU. In addition, the PKRU register is XSAVE-managed state and can thus
be read and written by instructions in the XSAVE feature set.

PFEC.PK (bit 5) is defined as protection key violations.

The specification of Protection Keys can be found at SDM (4.6.2, volume 3)

The kernel native patchset have not yet been merged to upstream, you can found
at git:// pkeys-v007.

Huaitong Han (7):
  KVM, pkeys: expose CPUID/CR4 to guest
  KVM, pkeys: disable pkeys for guests in non-paging mode
  KVM, pkeys: update memeory permission bitmask for pkeys
  KVM, pkeys: add pkeys support for permission_fault logic
  KVM, pkeys: Add pkeys support for gva_to_gpa funcions
  KVM, pkeys: add pkeys support for xsave state
  KVM, pkeys: disable PKU feature without ept

 arch/x86/include/asm/kvm_host.h | 11 +++++---
 arch/x86/kvm/cpuid.c            | 24 ++++++++++++++++--
 arch/x86/kvm/cpuid.h            |  8 ++++++
 arch/x86/kvm/mmu.c              | 32 +++++++++++++++++++++--
 arch/x86/kvm/mmu.h              | 56 +++++++++++++++++++++++++++++++++++++----
 arch/x86/kvm/paging_tmpl.h      | 18 ++++++++++---
 arch/x86/kvm/vmx.c              | 10 ++++----
 arch/x86/kvm/x86.c              | 27 ++++++++++++++------
 arch/x86/kvm/x86.h              |  3 ++-
 9 files changed, 161 insertions(+), 28 deletions(-)


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