On 8/30/24 09:34, Deepak Gupta wrote:
+bool cpu_get_bcfien(CPURISCVState *env)
It occurs to me that a better name would be "cpu_get_sspen".
The backward cfi is merely a consequence of the shadow stack.
+{
+ /* no cfi extension, return false */
+ if (!env_archcpu(env)->cfg.ext_zicfiss) {
+ return false;
+ }
+
+ switch (env->priv) {
+ case PRV_U:
+ if (riscv_has_ext(env, RVS)) {
+ return env->senvcfg & SENVCFG_SSE;
+ }
+ return env->menvcfg & MENVCFG_SSE;
+#ifndef CONFIG_USER_ONLY
+ case PRV_S:
+ if (env->virt_enabled) {
+ return env->henvcfg & HENVCFG_SSE;
+ }
+ return env->menvcfg & MENVCFG_SSE;
+ case PRV_M: /* M-mode shadow stack is always on if hart implements */
+ return true;
From the manual:
Activating Zicfiss in M-mode is currently not supported. Additionally, when
S-mode is not
implemented, activation in U-mode is also not supported.
So two of the cases above are wrong.
r~
