[PATCH for-8.1 13/17] target/riscv/cpu.c: split riscv_cpu_validate_priv_spec()

[Daniel Henrique Barboza <dbarboza@ventanamicro.com>]

This function will validate and change/disable extensions that aren't
compatible with a certain spec version. Since the function is called
at the start of riscv_cpu_validate_set_extensions(), we're disabling
extensions without guaranteeing that they aren't being turned on again
after the validation step.

Create a new riscv_cpu_disable_priv_spec_isa_exts() helper and call it
at the end of riscv_cpu_validate_set_extensions(), right before
re-calculating the misa_ext value with the current config. This will
ensure that we're not re-enabling extensions that should be disabled by
the spec rula by accident.

Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
---
 target/riscv/cpu.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index a564de01df..49f0fd2c11 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -942,7 +942,7 @@ static void riscv_cpu_validate_v(CPURISCVState *env, RISCVCPUConfig *cfg,
 static void riscv_cpu_validate_priv_spec(RISCVCPU *cpu, Error **errp)
 {
     CPURISCVState *env = &cpu->env;
-    int i, priv_version = -1;
+    int priv_version = -1;
 
     if (cpu->cfg.priv_spec) {
         if (!g_strcmp0(cpu->cfg.priv_spec, "v1.12.0")) {
@@ -962,6 +962,12 @@ static void riscv_cpu_validate_priv_spec(RISCVCPU *cpu, Error **errp)
     if (priv_version >= PRIV_VERSION_1_10_0) {
         env->priv_ver = priv_version;
     }
+}
+
+static void riscv_cpu_disable_priv_spec_isa_exts(RISCVCPU *cpu)
+{
+    CPURISCVState *env = &cpu->env;
+    int i;
 
     /* Force disable extensions if priv spec version does not match */
     for (i = 0; i < ARRAY_SIZE(isa_edata_arr); i++) {
@@ -1183,6 +1189,12 @@ static void riscv_cpu_validate_set_extensions(RISCVCPU *cpu, Error **errp)
         cpu->cfg.ext_zksh = true;
     }
 
+    /*
+     * Disable isa extensions based on priv spec after we
+     * validated and set everything we need.
+     */
+    riscv_cpu_disable_priv_spec_isa_exts(cpu);
+
     ext = riscv_get_misa_ext_with_cpucfg(&cpu->cfg);
 
     env->misa_ext_mask = env->misa_ext = ext;
-- 
2.39.2