Currently, the sbi_pmu_test continues if the exception type is illegal instruction because access to hpmcounter will generate that. However, we may get illegal for other reasons as well which should result in test assertion.
Use the stval to decode the exact type of instructions and which csrs are being accessed if it is csr access instructions. Assert in all cases except if it is a csr access instructions that access valid PMU related registers.
Signed-off-by: Atish Patra atishp@rivosinc.com --- tools/testing/selftests/kvm/riscv/sbi_pmu_test.c | 32 ++++++++++++++++++++++++ 1 file changed, 32 insertions(+)
diff --git a/tools/testing/selftests/kvm/riscv/sbi_pmu_test.c b/tools/testing/selftests/kvm/riscv/sbi_pmu_test.c index 03406de4989d..11bde69b5238 100644 --- a/tools/testing/selftests/kvm/riscv/sbi_pmu_test.c +++ b/tools/testing/selftests/kvm/riscv/sbi_pmu_test.c @@ -128,11 +128,43 @@ static void stop_counter(unsigned long counter, unsigned long stop_flags) "Unable to stop counter %ld error %ld\n", counter, ret.error); }
+#define INSN_OPCODE_MASK 0x007c +#define INSN_OPCODE_SHIFT 2 +#define INSN_OPCODE_SYSTEM 28 + +#define INSN_MASK_FUNCT3 0x7000 +#define INSN_SHIFT_FUNCT3 12 + +#define INSN_CSR_MASK 0xfff00000 +#define INSN_CSR_SHIFT 20 + +#define GET_RM(insn) (((insn) & INSN_MASK_FUNCT3) >> INSN_SHIFT_FUNCT3) +#define GET_CSR_NUM(insn) (((insn) & INSN_CSR_MASK) >> INSN_CSR_SHIFT) + static void guest_illegal_exception_handler(struct ex_regs *regs) { + unsigned long insn; + int opcode, csr_num, funct3; + __GUEST_ASSERT(regs->cause == EXC_INST_ILLEGAL, "Unexpected exception handler %lx\n", regs->cause);
+ insn = regs->stval; + opcode = (insn & INSN_OPCODE_MASK) >> INSN_OPCODE_SHIFT; + __GUEST_ASSERT(opcode == INSN_OPCODE_SYSTEM, + "Unexpected instruction with opcode 0x%x insn 0x%lx\n", opcode, insn); + + csr_num = GET_CSR_NUM(insn); + funct3 = GET_RM(insn); + /* Validate if it is a CSR read/write operation */ + __GUEST_ASSERT(funct3 <= 7 && (funct3 != 0 || funct3 != 4), + "Unexpected system opcode with funct3 0x%x csr_num 0x%x\n", + funct3, csr_num); + + /* Validate if it is a HPMCOUNTER CSR operation */ + __GUEST_ASSERT(csr_num == CSR_CYCLE || csr_num <= CSR_HPMCOUNTER31, + "Unexpected csr_num 0x%x\n", csr_num); + illegal_handler_invoked = true; /* skip the trapping instruction */ regs->epc += 4;