[PATCH 1/4] target/riscv: Make MPV only work when MPP != PRV_M

[Weiwei Li <liweiwei@iscas.ac.cn>]

Upon MRET or explicit memory access with MPRV=1, MPV should be ignored
when MPP=PRV_M.

Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
---
 target/riscv/cpu_helper.c | 3 ++-
 target/riscv/op_helper.c  | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
index 09ea227ceb..bd892c05d4 100644
--- a/target/riscv/cpu_helper.c
+++ b/target/riscv/cpu_helper.c
@@ -46,7 +46,8 @@ int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch)
 
         if (mode == PRV_M && get_field(status, MSTATUS_MPRV)) {
             mode = get_field(env->mstatus, MSTATUS_MPP);
-            virt = get_field(env->mstatus, MSTATUS_MPV);
+            virt = get_field(env->mstatus, MSTATUS_MPV) &&
+                   (mode != PRV_M);
             if (virt) {
                 status = env->vsstatus;
             }
diff --git a/target/riscv/op_helper.c b/target/riscv/op_helper.c
index f563dc3981..9cdb9cdd06 100644
--- a/target/riscv/op_helper.c
+++ b/target/riscv/op_helper.c
@@ -335,7 +335,8 @@ target_ulong helper_mret(CPURISCVState *env)
         riscv_raise_exception(env, RISCV_EXCP_INST_ACCESS_FAULT, GETPC());
     }
 
-    target_ulong prev_virt = get_field(env->mstatus, MSTATUS_MPV);
+    target_ulong prev_virt = get_field(env->mstatus, MSTATUS_MPV) &&
+                             (prev_priv != PRV_M);
     mstatus = set_field(mstatus, MSTATUS_MIE,
                         get_field(mstatus, MSTATUS_MPIE));
     mstatus = set_field(mstatus, MSTATUS_MPIE, 1);
-- 
2.25.1