diff --git a/target/riscv/pmp.c b/target/riscv/pmp.c index 3afa16917e..8fc313990a 100644 --- a/target/riscv/pmp.c +++ b/target/riscv/pmp.c @@ -76,6 +76,44 @@ static int pmp_is_readonly(CPURISCVState *env, uint32_t pmp_index) return pmp_is_locked(env, pmp_index) && !MSECCFG_RLB_ISSET(env); } +/* + * Check whether `val` is an invalid Smepmp config value + */ +static int pmp_is_invalid_smepmp_cfg(CPURISCVState *env, uint8_t val) +{ + /* No check if mseccfg.MML is not set or if mseccfg.RLB is set */ + if (!MSECCFG_MML_ISSET(env) || MSECCFG_RLB_ISSET(env)) { + return 0; + } + + /* + * Adding a rule with executable privileges that either is M-mode-only + * or a locked Shared-Region is not possible + */ + switch (pmp_get_smepmp_operation(val)) { + case 0: + case 1: + case 2: + case 3: + case 4: + case 5: + case 6: + case 7: + case 8: + case 12: + case 14: + case 15: + return 0; + case 9: + case 10: + case 11: + case 13: + return 1; + default: + g_assert_not_reached(); + } +} + /* * Count the number of active rules. */ @@ -104,44 +142,13 @@ static inline uint8_t pmp_read_cfg(CPURISCVState *env, uint32_t pmp_index) static bool pmp_write_cfg(CPURISCVState *env, uint32_t pmp_index, uint8_t val) { if (pmp_index < MAX_RISCV_PMPS) { - bool readonly = true; - - if (riscv_cpu_cfg(env)->ext_smepmp) { - /* mseccfg.RLB is set */ - if (MSECCFG_RLB_ISSET(env)) { - readonly = false; - } - - /* mseccfg.MML is not set */ - if (!MSECCFG_MML_ISSET(env) && !pmp_is_readonly(env, pmp_index)) { - readonly = false; - } - - /* mseccfg.MML is set */ - if (MSECCFG_MML_ISSET(env)) { - /* not adding execute bit */ - if ((val & PMP_LOCK) != 0 && (val & PMP_EXEC) != PMP_EXEC) { - readonly = false; - } - /* shared region and not adding X bit */ - if ((val & PMP_LOCK) != PMP_LOCK && - (val & 0x7) != (PMP_WRITE | PMP_EXEC)) { - readonly = false; - } - } - } else { - readonly = pmp_is_readonly(env, pmp_index); - } - - if (readonly) { + if (pmp_is_readonly(env, pmp_index)) { qemu_log_mask(LOG_GUEST_ERROR, "ignoring pmpcfg write - read only\n"); - } else if (env->pmp_state.pmp[pmp_index].cfg_reg != val) { - /* If !mseccfg.MML then ignore writes with encoding RW=01 */ - if ((val & PMP_WRITE) && !(val & PMP_READ) && - !MSECCFG_MML_ISSET(env)) { - return false; - } + } else if (pmp_is_invalid_smepmp_cfg(env, val)) { + qemu_log_mask(LOG_GUEST_ERROR, + "ignoring pmpcfg write - invalid\n"); + } else { env->pmp_state.pmp[pmp_index].cfg_reg = val; pmp_update_rule_addr(env, pmp_index); return true;