On Thu, Mar 30, 2023 at 11:59 PM Weiwei Li <liwei...@iscas.ac.cn> wrote: > > The MPP will be set to the least-privileged supported mode (U if > U-mode is implemented, else M).
I don't think this is right, the spec in section 8.6.4 says this: "MRET then in mstatus/mstatush sets MPV=0, MPP=0, MIE=MPIE, and MPIE=1" So it should just always be 0 (PRV_U is 0) Alistair > > Signed-off-by: Weiwei Li <liwei...@iscas.ac.cn> > Signed-off-by: Junqiang Wang <wangjunqi...@iscas.ac.cn> > --- > target/riscv/op_helper.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/target/riscv/op_helper.c b/target/riscv/op_helper.c > index 84ee018f7d..991f06d98d 100644 > --- a/target/riscv/op_helper.c > +++ b/target/riscv/op_helper.c > @@ -339,7 +339,8 @@ target_ulong helper_mret(CPURISCVState *env) > mstatus = set_field(mstatus, MSTATUS_MIE, > get_field(mstatus, MSTATUS_MPIE)); > mstatus = set_field(mstatus, MSTATUS_MPIE, 1); > - mstatus = set_field(mstatus, MSTATUS_MPP, PRV_U); > + mstatus = set_field(mstatus, MSTATUS_MPP, > + riscv_has_ext(env, RVU) ? PRV_U : PRV_M); > mstatus = set_field(mstatus, MSTATUS_MPV, 0); > if ((env->priv_ver >= PRIV_VERSION_1_12_0) && (prev_priv != PRV_M)) { > mstatus = set_field(mstatus, MSTATUS_MPRV, 0); > -- > 2.25.1 > >