[PATCH v3 0/9] Cleanup/Optimise KUAP (v3)

[Christophe Leroy]

This series is cleaning up a bit KUAP in preparation of using objtool
to validate UACCESS.

There are two main changes in this series:

1/ Simplification of KUAP on book3s/32

2/ Using ASM features on 32 bits and booke as suggested by Nic.

Those changes will be required for objtool UACCESS validation, but
even before they are worth it, especially the simplification on 32s.

Changes in v3:
- Rearranged book3s/32 simplification in order to ease objtool UACCESS
check implementation (patches 7 and 9)

Christophe Leroy (9):
  powerpc/kuap: Avoid unnecessary reads of MD_AP
  powerpc/kuap: Avoid useless jump_label on empty function
  powerpc/kuap: Fold kuep_is_disabled() into its only user
  powerpc/features: Add capability to update mmu features later
  powerpc/kuap: MMU_FTR_BOOK3S_KUAP becomes MMU_FTR_KUAP
  powerpc/kuap: Use MMU_FTR_KUAP on all and refactor disabling kuap
  powerpc/kuap: Simplify KUAP lock/unlock on BOOK3S/32
  powerpc/kuap: KUAP enabling/disabling functions must be
    __always_inline
  powerpc/kuap: Use ASM feature fixups instead of static branches

 arch/powerpc/include/asm/book3s/32/kup.h      | 123 ++++++++----------
 .../powerpc/include/asm/book3s/64/hash-pkey.h |   2 +-
 arch/powerpc/include/asm/book3s/64/kup.h      |  54 ++++----
 arch/powerpc/include/asm/bug.h                |   1 +
 arch/powerpc/include/asm/feature-fixups.h     |   1 +
 arch/powerpc/include/asm/kup.h                |  91 +++++--------
 arch/powerpc/include/asm/mmu.h                |   4 +-
 arch/powerpc/include/asm/nohash/32/kup-8xx.h  |  62 +++++----
 arch/powerpc/include/asm/nohash/kup-booke.h   |  68 +++++-----
 arch/powerpc/include/asm/uaccess.h            |   6 +-
 arch/powerpc/kernel/cputable.c                |   4 +
 arch/powerpc/kernel/syscall.c                 |   2 +-
 arch/powerpc/kernel/traps.c                   |   2 +-
 arch/powerpc/lib/feature-fixups.c             |  31 ++++-
 arch/powerpc/mm/book3s32/kuap.c               |  20 +--
 arch/powerpc/mm/book3s32/mmu_context.c        |   2 +-
 arch/powerpc/mm/book3s64/pkeys.c              |   2 +-
 arch/powerpc/mm/init_32.c                     |   2 +
 arch/powerpc/mm/nohash/kup.c                  |   8 +-
 19 files changed, 222 insertions(+), 263 deletions(-)

-- 
2.41.0