diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 49566d3c08..8225e9bb4b 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -192,6 +192,11 @@ static RISCVException cfi_ss(CPURISCVState *env, int csrno)
         return RISCV_EXCP_ILLEGAL_INST;
     }
 
+    /* If ext implemented, M-mode always have access to SSP CSR */
+    if (env->priv == PRV_M) {
+        return RISCV_EXCP_NONE;
+    }
+
     /* if bcfi not active for current env, access to csr is illegal */
     if (!cpu_get_bcfien(env)) {
 #if !defined(CONFIG_USER_ONLY)