[RFC PATCH 0/7] Support protection keys in an AMD EPYC-Milan VM

[David Edmondson <david.edmondson@oracle.com>]

AMD EPYC-Milan CPUs introduced support for protection keys, previously
available only with Intel CPUs.

AMD chose to place the XSAVE state component for the protection keys
at a different offset in the XSAVE state area than that chosen by
Intel.

To accommodate this, modify QEMU to behave appropriately on AMD
systems, allowing a VM to properly take advantage of the new feature.

Further, avoid manipulating XSAVE state components that are not
present on AMD systems.

The code in patch 6 that changes the CPUID 0x0d leaf is mostly dumped
somewhere that seemed to work - I'm not sure where it really belongs.

David Edmondson (7):
  target/i386: Declare constants for XSAVE offsets
  target/i386: Use constants for XSAVE offsets
  target/i386: Clarify the padding requirements of X86XSaveArea
  target/i386: Prepare for per-vendor X86XSaveArea layout
  target/i386: Introduce AMD X86XSaveArea sub-union
  target/i386: Adjust AMD XSAVE PKRU area offset in CPUID leaf 0xd
  target/i386: Manipulate only AMD XSAVE state on AMD

 target/i386/cpu.c            | 19 +++++----
 target/i386/cpu.h            | 80 ++++++++++++++++++++++++++++--------
 target/i386/kvm/kvm.c        | 57 +++++++++----------------
 target/i386/tcg/fpu_helper.c | 20 ++++++---
 target/i386/xsave_helper.c   | 70 +++++++++++++++++++------------
 5 files changed, 152 insertions(+), 94 deletions(-)

-- 
2.30.2