[PATCH v7 00/28] Initial Prefixed Instruction support

Fri May 1 13:41:52 AEST 2020

A future revision of the ISA will introduce prefixed instructions. A
prefixed instruction is composed of a 4-byte prefix followed by a
4-byte suffix.

All prefixes have the major opcode 1. A prefix will never be a valid
word instruction. A suffix may be an existing word instruction or a
new instruction.

This series enables prefixed instructions and extends the instruction
emulation to support them. Then the places where prefixed instructions
might need to be emulated are updated.

v7 fixes compilation issues for some configs reported by Alistair
Popple.

v6 is based on feedback from Balamuruhan Suriyakumar, Alistair Popple,
Christophe Leroy and Segher Boessenkool.
The major changes:
    - Use the instruction type in more places that had been missed before
    - Fix issues with ppc32
    - Introduce new self tests for code patching and feature fixups

v5 is based on feedback from Nick Piggins, Michael Ellerman, Balamuruhan
Suriyakumar and Alistair Popple.
The major changes:
    - The ppc instruction type is now a struct
    - Series now just based on next
    - ppc_inst_masked() dropped
    - Space for xmon breakpoints allocated in an assembly file
    - "Add prefixed instructions to instruction data type" patch seperated in
      to smaller patches
    - Calling convention for create_branch() is changed
    - Some places which had not been updated to use the data type are now updated

v4 is based on feedback from Nick Piggins, Christophe Leroy and Daniel Axtens.
The major changes:
    - Move xmon breakpoints from data section to text section
    - Introduce a data type for instructions on powerpc

v3 is based on feedback from Christophe Leroy. The major changes:
    - Completely replacing store_inst() with patch_instruction() in
      xmon
    - Improve implementation of mread_instr() to not use mread().
    - Base the series on top of
      https://patchwork.ozlabs.org/patch/1232619/ as this will effect
      kprobes.
    - Some renaming and simplification of conditionals.

v2 incorporates feedback from Daniel Axtens and and Balamuruhan
S. The major changes are:
    - Squashing together all commits about SRR1 bits
    - Squashing all commits for supporting prefixed load stores
    - Changing abbreviated references to sufx/prfx -> suffix/prefix
    - Introducing macros for returning the length of an instruction
    - Removing sign extension flag from pstd/pld in sstep.c
    - Dropping patch  "powerpc/fault: Use analyse_instr() to check for
      store with updates to sp" from the series, it did not really fit
      with prefixed enablement in the first place and as reported by Greg
      Kurz did not work correctly.

Alistair Popple (1):
  powerpc: Enable Prefixed Instructions

Jordan Niethe (27):
  powerpc/xmon: Remove store_inst() for patch_instruction()
  powerpc/xmon: Move breakpoint instructions to own array
  powerpc/xmon: Move breakpoints to text section
  powerpc/xmon: Use bitwise calculations in_breakpoint_table()
  powerpc: Change calling convention for create_branch() et. al.
  powerpc: Use a macro for creating instructions from u32s
  powerpc: Use an accessor for instructions
  powerpc: Use a function for getting the instruction op code
  powerpc: Use a function for byte swapping instructions
  powerpc: Introduce functions for instruction equality
  powerpc: Use a datatype for instructions
  powerpc: Use a function for reading instructions
  powerpc: Add a probe_user_read_inst() function
  powerpc: Add a probe_kernel_read_inst() function
  powerpc/kprobes: Use patch_instruction()
  powerpc: Define and use __get_user_instr{,inatomic}()
  powerpc: Introduce a function for reporting instruction length
  powerpc/xmon: Use a function for reading instructions
  powerpc/xmon: Move insertion of breakpoint for xol'ing
  powerpc: Make test_translate_branch() independent of instruction
    length
  powerpc: Define new SRR1 bits for a future ISA version
  powerpc: Add prefixed instructions to instruction data type
  powerpc: Test prefixed code patching
  powerpc: Test prefixed instructions in feature fixups
  powerpc: Support prefixed instructions in alignment handler
  powerpc sstep: Add support for prefixed load/stores
  powerpc sstep: Add support for prefixed fixed-point arithmetic

 arch/powerpc/include/asm/code-patching.h |  37 +-
 arch/powerpc/include/asm/inst.h          | 106 ++++++
 arch/powerpc/include/asm/kprobes.h       |   2 +-
 arch/powerpc/include/asm/reg.h           |   7 +-
 arch/powerpc/include/asm/sstep.h         |  15 +-
 arch/powerpc/include/asm/uaccess.h       |  35 ++
 arch/powerpc/include/asm/uprobes.h       |   7 +-
 arch/powerpc/kernel/align.c              |  13 +-
 arch/powerpc/kernel/asm-offsets.c        |   8 +
 arch/powerpc/kernel/epapr_paravirt.c     |   7 +-
 arch/powerpc/kernel/hw_breakpoint.c      |   5 +-
 arch/powerpc/kernel/jump_label.c         |   5 +-
 arch/powerpc/kernel/kgdb.c               |   9 +-
 arch/powerpc/kernel/kprobes.c            |  24 +-
 arch/powerpc/kernel/mce_power.c          |   5 +-
 arch/powerpc/kernel/module_64.c          |   3 +-
 arch/powerpc/kernel/optprobes.c          |  91 +++--
 arch/powerpc/kernel/optprobes_head.S     |   3 +
 arch/powerpc/kernel/security.c           |   9 +-
 arch/powerpc/kernel/setup_32.c           |   8 +-
 arch/powerpc/kernel/trace/ftrace.c       | 160 ++++----
 arch/powerpc/kernel/traps.c              |  20 +-
 arch/powerpc/kernel/uprobes.c            |   5 +-
 arch/powerpc/kernel/vecemu.c             |  20 +-
 arch/powerpc/kvm/book3s_hv_nested.c      |   2 +-
 arch/powerpc/kvm/book3s_hv_rm_mmu.c      |   2 +-
 arch/powerpc/kvm/emulate_loadstore.c     |   2 +-
 arch/powerpc/lib/Makefile                |   2 +-
 arch/powerpc/lib/code-patching.c         | 308 ++++++++-------
 arch/powerpc/lib/feature-fixups-test.S   |  68 ++++
 arch/powerpc/lib/feature-fixups.c        | 159 ++++++--
 arch/powerpc/lib/inst.c                  |  69 ++++
 arch/powerpc/lib/sstep.c                 | 461 ++++++++++++++++-------
 arch/powerpc/lib/test_code-patching.S    |  19 +
 arch/powerpc/lib/test_emulate_step.c     |  56 +--
 arch/powerpc/mm/fault.c                  |  15 +-
 arch/powerpc/perf/core-book3s.c          |   4 +-
 arch/powerpc/xmon/Makefile               |   2 +-
 arch/powerpc/xmon/xmon.c                 |  94 +++--
 arch/powerpc/xmon/xmon_bpts.S            |  11 +
 arch/powerpc/xmon/xmon_bpts.h            |  14 +
 41 files changed, 1308 insertions(+), 584 deletions(-)
 create mode 100644 arch/powerpc/include/asm/inst.h
 create mode 100644 arch/powerpc/lib/inst.c
 create mode 100644 arch/powerpc/lib/test_code-patching.S
 create mode 100644 arch/powerpc/xmon/xmon_bpts.S
 create mode 100644 arch/powerpc/xmon/xmon_bpts.h

-- 
2.17.1