diff options
Diffstat (limited to 'arch/riscv/kernel/probes/simulate-insn.c')
| -rw-r--r-- | arch/riscv/kernel/probes/simulate-insn.c | 130 |
1 files changed, 114 insertions, 16 deletions
diff --git a/arch/riscv/kernel/probes/simulate-insn.c b/arch/riscv/kernel/probes/simulate-insn.c index d73e96f6ed7c..6c166029079c 100644 --- a/arch/riscv/kernel/probes/simulate-insn.c +++ b/arch/riscv/kernel/probes/simulate-insn.c @@ -24,7 +24,7 @@ static inline bool rv_insn_reg_set_val(struct pt_regs *regs, u32 index, unsigned long val) { if (index == 0) - return false; + return true; else if (index <= 31) *((unsigned long *)regs + index) = val; else @@ -71,11 +71,11 @@ bool __kprobes simulate_jalr(u32 opcode, unsigned long addr, struct pt_regs *reg u32 rd_index = (opcode >> 7) & 0x1f; u32 rs1_index = (opcode >> 15) & 0x1f; - ret = rv_insn_reg_set_val(regs, rd_index, addr + 4); + ret = rv_insn_reg_get_val(regs, rs1_index, &base_addr); if (!ret) return ret; - ret = rv_insn_reg_get_val(regs, rs1_index, &base_addr); + ret = rv_insn_reg_set_val(regs, rd_index, addr + 4); if (!ret) return ret; @@ -136,13 +136,6 @@ bool __kprobes simulate_auipc(u32 opcode, unsigned long addr, struct pt_regs *re #define branch_offset(opcode) \ sign_extend32((branch_imm(opcode)), 12) -#define BRANCH_BEQ 0x0 -#define BRANCH_BNE 0x1 -#define BRANCH_BLT 0x4 -#define BRANCH_BGE 0x5 -#define BRANCH_BLTU 0x6 -#define BRANCH_BGEU 0x7 - bool __kprobes simulate_branch(u32 opcode, unsigned long addr, struct pt_regs *regs) { /* @@ -169,22 +162,22 @@ bool __kprobes simulate_branch(u32 opcode, unsigned long addr, struct pt_regs *r offset_tmp = branch_offset(opcode); switch (branch_funct3(opcode)) { - case BRANCH_BEQ: + case RVG_FUNCT3_BEQ: offset = (rs1_val == rs2_val) ? offset_tmp : 4; break; - case BRANCH_BNE: + case RVG_FUNCT3_BNE: offset = (rs1_val != rs2_val) ? offset_tmp : 4; break; - case BRANCH_BLT: + case RVG_FUNCT3_BLT: offset = ((long)rs1_val < (long)rs2_val) ? offset_tmp : 4; break; - case BRANCH_BGE: + case RVG_FUNCT3_BGE: offset = ((long)rs1_val >= (long)rs2_val) ? offset_tmp : 4; break; - case BRANCH_BLTU: + case RVG_FUNCT3_BLTU: offset = (rs1_val < rs2_val) ? offset_tmp : 4; break; - case BRANCH_BGEU: + case RVG_FUNCT3_BGEU: offset = (rs1_val >= rs2_val) ? offset_tmp : 4; break; default: @@ -195,3 +188,108 @@ bool __kprobes simulate_branch(u32 opcode, unsigned long addr, struct pt_regs *r return true; } + +bool __kprobes simulate_c_j(u32 opcode, unsigned long addr, struct pt_regs *regs) +{ + /* + * 15 13 12 2 1 0 + * | funct3 | offset[11|4|9:8|10|6|7|3:1|5] | opcode | + * 3 11 2 + */ + + s32 offset; + + offset = ((opcode >> 3) & 0x7) << 1; + offset |= ((opcode >> 11) & 0x1) << 4; + offset |= ((opcode >> 2) & 0x1) << 5; + offset |= ((opcode >> 7) & 0x1) << 6; + offset |= ((opcode >> 6) & 0x1) << 7; + offset |= ((opcode >> 9) & 0x3) << 8; + offset |= ((opcode >> 8) & 0x1) << 10; + offset |= ((opcode >> 12) & 0x1) << 11; + + instruction_pointer_set(regs, addr + sign_extend32(offset, 11)); + + return true; +} + +static bool __kprobes simulate_c_jr_jalr(u32 opcode, unsigned long addr, struct pt_regs *regs, + bool is_jalr) +{ + /* + * 15 12 11 7 6 2 1 0 + * | funct4 | rs1 | rs2 | op | + * 4 5 5 2 + */ + + unsigned long jump_addr; + + u32 rs1 = (opcode >> 7) & 0x1f; + + if (rs1 == 0) /* C.JR is only valid when rs1 != x0 */ + return false; + + if (!rv_insn_reg_get_val(regs, rs1, &jump_addr)) + return false; + + if (is_jalr && !rv_insn_reg_set_val(regs, 1, addr + 2)) + return false; + + instruction_pointer_set(regs, jump_addr); + + return true; +} + +bool __kprobes simulate_c_jr(u32 opcode, unsigned long addr, struct pt_regs *regs) +{ + return simulate_c_jr_jalr(opcode, addr, regs, false); +} + +bool __kprobes simulate_c_jalr(u32 opcode, unsigned long addr, struct pt_regs *regs) +{ + return simulate_c_jr_jalr(opcode, addr, regs, true); +} + +static bool __kprobes simulate_c_bnez_beqz(u32 opcode, unsigned long addr, struct pt_regs *regs, + bool is_bnez) +{ + /* + * 15 13 12 10 9 7 6 2 1 0 + * | funct3 | offset[8|4:3] | rs1' | offset[7:6|2:1|5] | op | + * 3 3 3 5 2 + */ + + s32 offset; + u32 rs1; + unsigned long rs1_val; + + rs1 = 0x8 | ((opcode >> 7) & 0x7); + + if (!rv_insn_reg_get_val(regs, rs1, &rs1_val)) + return false; + + if ((rs1_val != 0 && is_bnez) || (rs1_val == 0 && !is_bnez)) { + offset = ((opcode >> 3) & 0x3) << 1; + offset |= ((opcode >> 10) & 0x3) << 3; + offset |= ((opcode >> 2) & 0x1) << 5; + offset |= ((opcode >> 5) & 0x3) << 6; + offset |= ((opcode >> 12) & 0x1) << 8; + offset = sign_extend32(offset, 8); + } else { + offset = 2; + } + + instruction_pointer_set(regs, addr + offset); + + return true; +} + +bool __kprobes simulate_c_bnez(u32 opcode, unsigned long addr, struct pt_regs *regs) +{ + return simulate_c_bnez_beqz(opcode, addr, regs, true); +} + +bool __kprobes simulate_c_beqz(u32 opcode, unsigned long addr, struct pt_regs *regs) +{ + return simulate_c_bnez_beqz(opcode, addr, regs, false); +} |