[PATCH 0/2] Reintroduce PROT_SAO

[Shawn Anastasio]

This set re-introduces the PROT_SAO prot flag removed in
Commit 5c9fa16e8abd ("powerpc/64s: Remove PROT_SAO support").

To address concerns regarding live migration of guests using SAO
to P10 hosts without SAO support, the flag is disabled by default
in LPARs. A new config option, PPC_PROT_SAO_LPAR was added to
allow users to explicitly enable it if they will not be running
in an environment where this is a conern.

Shawn Anastasio (2):
  Revert "powerpc/64s: Remove PROT_SAO support"
  powerpc/64s: Disallow PROT_SAO in LPARs by default

 arch/powerpc/Kconfig                          | 12 ++++++
 arch/powerpc/include/asm/book3s/64/pgtable.h  |  8 ++--
 arch/powerpc/include/asm/cputable.h           | 10 ++---
 arch/powerpc/include/asm/mman.h               | 31 ++++++++++++--
 arch/powerpc/include/asm/nohash/64/pgtable.h  |  2 +
 arch/powerpc/include/uapi/asm/mman.h          |  2 +-
 arch/powerpc/kernel/dt_cpu_ftrs.c             |  2 +-
 arch/powerpc/mm/book3s64/hash_utils.c         |  2 +
 include/linux/mm.h                            |  2 +
 include/trace/events/mmflags.h                |  2 +
 mm/ksm.c                                      |  4 ++
 tools/testing/selftests/powerpc/mm/.gitignore |  1 +
 tools/testing/selftests/powerpc/mm/Makefile   |  4 +-
 tools/testing/selftests/powerpc/mm/prot_sao.c | 42 +++++++++++++++++++
 14 files changed, 107 insertions(+), 17 deletions(-)
 create mode 100644 tools/testing/selftests/powerpc/mm/prot_sao.c

-- 
2.28.0