[PATCH v8 0/4] Add kprobe and kretprobe support for LoongArch

[Tiezhu Yang]

v8:
  -- Put "regs->csr_prmd &= ~CSR_PRMD_PIE;" ahead to save one line
  -- Add code comment of preempt_disable()
  -- Put kprobe_page_fault() in __do_page_fault()
  -- Modify the check condition of break insn in kprobe_breakpoint_handler()

v7:
  -- Remove stop_machine_cpuslocked() related code

v6:
  -- Add a new patch to redefine larch_insn_patch_text() with
     stop_machine_cpuslocked()
  -- Modify kprobe_breakpoint_handler() to consider the original
     insn is break and return the correct value
  -- Modify do_bp() to refresh bcode when original insn is break

v5:
  -- Rebase on the latest code
  -- Use stop_machine_cpuslocked() to modify insn to avoid CPU race

v4:
  -- Remove kprobe_exceptions_notify() in kprobes.c
  -- Call kprobe_breakpoint_handler() and kprobe_singlestep_handler()
     in do_bp()

v3:
  -- Rebase on the latest code
  -- Check the alignment of PC in simu_branch() and simu_pc()
  -- Add ibar in flush_insn_slot()
  -- Rename kprobe_{pre,post}_handler() to {post_}kprobe_handler
  -- Add preempt_disable() and preempt_enable_no_resched()
  -- Remove r0 save/restore and do some minor changes
     in kprobes_trampoline.S
  -- Do not enable CONFIG_KPROBES by default

v2:
  -- Split simu_branch() and simu_pc() into a single patch
  -- Call kprobe_page_fault() in do_page_fault()
  -- Add kprobes_trampoline.S for kretprobe

Tiezhu Yang (4):
  LoongArch: Simulate branch and PC instructions
  LoongArch: Add kprobe support
  LoongArch: Add kretprobe support
  samples/kprobes: Add LoongArch support

 arch/loongarch/Kconfig                     |   2 +
 arch/loongarch/include/asm/inst.h          |  27 +++
 arch/loongarch/include/asm/kprobes.h       |  59 +++++
 arch/loongarch/include/asm/ptrace.h        |   1 +
 arch/loongarch/kernel/Makefile             |   2 +
 arch/loongarch/kernel/inst.c               | 123 +++++++++++
 arch/loongarch/kernel/kprobes.c            | 333 +++++++++++++++++++++++++++++
 arch/loongarch/kernel/kprobes_trampoline.S |  96 +++++++++
 arch/loongarch/kernel/traps.c              |  13 +-
 arch/loongarch/mm/fault.c                  |   3 +
 samples/kprobes/kprobe_example.c           |   8 +
 11 files changed, 663 insertions(+), 4 deletions(-)
 create mode 100644 arch/loongarch/include/asm/kprobes.h
 create mode 100644 arch/loongarch/kernel/kprobes.c
 create mode 100644 arch/loongarch/kernel/kprobes_trampoline.S

-- 
2.1.0