[0/4] x86: RSBA and RRSBA handling

Message

Andrew Cooper May 26, 2023, 11:06 a.m. UTC

This series deals with the hanlding of the RSBA and RRSBA bits across all
parts and all mistakes encountered in various microcode versions.

With it in place, here are some examples from various generations of Intel
hardware:

  BDX Raw
  BDX Host
  BDX HVM Max   rsba

  KBL Raw       rsba misc-pkg-ctrl energy-ctrl
  KBL Host      rsba misc-pkg-ctrl energy-ctrl
  KBL HVM Max   rsba

  SKX Raw       rsba misc-pkg-ctrl energy-ctrl
  SKX Host      rsba misc-pkg-ctrl energy-ctrl
  SKX HVM Max   rsba

  CFL Raw       rdcl-no eibrs skip-l1dfl mds-no tsx-ctrl misc-pkg-ctrl energy-ctrl fb-clear
  CFL Host      rdcl-no eibrs rsba skip-l1dfl mds-no tsx-ctrl misc-pkg-ctrl energy-ctrl fb-clear rrsba
  CFL HVM Max   rdcl-no eibrs rsba mds-no fb-clear rrsba

  CLX Raw       rdcl-no eibrs skip-l1dfl mds-no tsx-ctrl misc-pkg-ctrl energy-ctrl sbdr-ssdp-no psdp-no fb-clear rrsba
  CLX Host      rdcl-no eibrs rsba skip-l1dfl mds-no tsx-ctrl misc-pkg-ctrl energy-ctrl sbdr-ssdp-no psdp-no fb-clear rrsba
  CLX HVM Max   rdcl-no eibrs rsba mds-no sbdr-ssdp-no psdp-no fb-clear rrsba

  SPR Raw       rdcl-no eibrs skip-l1dfl mds-no if-pschange-mc-no tsx-ctrl taa-no misc-pkg-ctrl energy-ctrl
  SPR Host      rdcl-no eibrs rsba skip-l1dfl mds-no if-pschange-mc-no tsx-ctrl taa-no misc-pkg-ctrl energy-ctrl rrsba
  SPR HVM Max   rdcl-no eibrs rsba mds-no if-pschange-mc-no taa-no rrsba


Of note:
 * The SPR CPU is pre-release and didn't get the MMIO ucode in the end
   (sbdr-ssdp-no psdp-no fb-clear).
 * SKX/KBL enumerate RSBA following the energy filtering microcode.  Prior to
   that, they don't enumerate MSR_ARCH_CAPS at all.
 * CFL and SPR fails to enumerate both RSBA and RRSBA.  CLX fails to enumerate
   RSBA.  These should be addressed in due course.


Andrew Cooper (4):
  x86/spec-ctrl: Rename retpoline_safe() to retpoline_calculations()
  x86/spec-ctrl: Synthesize missing RSBA/RRSBA bits
  x86/cpu-policy: Rearrange guest_common_default_feature_adjustments()
  x86/cpu-policy: Derive {,R}RSBA for guest policies

 xen/arch/x86/cpu-policy.c             | 59 ++++++++++++++------
 xen/arch/x86/include/asm/cpufeature.h |  1 +
 xen/arch/x86/spec_ctrl.c              | 78 +++++++++++++++++++++------
 xen/tools/gen-cpuid.py                |  5 +-
 4 files changed, 111 insertions(+), 32 deletions(-)