arch/riscv/kernel/probes/decode-insn.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2
   3 #include <linux/kernel.h>
   4 #include <linux/kprobes.h>
   5 #include <linux/module.h>
   6 #include <linux/kallsyms.h>
   7 #include <asm/sections.h>
   8
   9 #include "decode-insn.h"
  10 #include "simulate-insn.h"
  11
  12 /* Return:
  13  *   INSN_REJECTED     If instruction is one not allowed to kprobe,
  14  *   INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot.
  15  */
  16 enum probe_insn __kprobes
  17 riscv_probe_decode_insn(probe_opcode_t *addr, struct arch_probe_insn *api)
  18 {
  19         probe_opcode_t insn = *addr;
  20
  21         /*
  22          * Reject instructions list:
  23          */
  24         RISCV_INSN_REJECTED(system,             insn);
  25         RISCV_INSN_REJECTED(fence,              insn);
  26
  27         /*
  28          * Simulate instructions list:
  29          * TODO: the REJECTED ones below need to be implemented
  30          */
  31 #ifdef CONFIG_RISCV_ISA_C
  32         RISCV_INSN_REJECTED(c_j,                insn);
  33         RISCV_INSN_REJECTED(c_jr,               insn);
  34         RISCV_INSN_REJECTED(c_jal,              insn);
  35         RISCV_INSN_REJECTED(c_jalr,             insn);
  36         RISCV_INSN_REJECTED(c_beqz,             insn);
  37         RISCV_INSN_REJECTED(c_bnez,             insn);
  38         RISCV_INSN_REJECTED(c_ebreak,           insn);
  39 #endif
  40
  41         RISCV_INSN_REJECTED(auipc,              insn);
  42         RISCV_INSN_REJECTED(branch,             insn);
  43
  44         RISCV_INSN_SET_SIMULATE(jal,            insn);
  45         RISCV_INSN_SET_SIMULATE(jalr,           insn);
  46
  47         return INSN_GOOD;
  48 }