Re: [PATCH v3 9/9] target/riscv: Use a smaller guess size for no-MMU PMP

[Alistair Francis]

On Wed, May 20, 2020 at 6:52 PM Bin Meng <address@hidden> wrote:
>
> On Wed, May 20, 2020 at 5:40 AM Alistair Francis
> <address@hidden> wrote:
> >
> > Signed-off-by: Alistair Francis <address@hidden>
> > ---
> >  target/riscv/pmp.c | 14 +++++++++-----
> >  1 file changed, 9 insertions(+), 5 deletions(-)
> >
> > diff --git a/target/riscv/pmp.c b/target/riscv/pmp.c
> > index 0e6b640fbd..607a991260 100644
> > --- a/target/riscv/pmp.c
> > +++ b/target/riscv/pmp.c
> > @@ -233,12 +233,16 @@ bool pmp_hart_has_privs(CPURISCVState *env, 
> > target_ulong addr,
> >          return true;
> >      }
> >
> > -    /*
> > -     * if size is unknown (0), assume that all bytes
> > -     * from addr to the end of the page will be accessed.
> > -     */
> >      if (size == 0) {
> > -        pmp_size = -(addr | TARGET_PAGE_MASK);
> > +        if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
>
> My previous comments were not fully addressed. I think the logic should be:
>
> if (riscv_feature(env, RISCV_FEATURE_MMU))
>
> Otherwise it does not match your comment and the commit title.

Ah! You are right. This uncovered a bug with how we set the MMU as
well. I have fixed this and added a new patch.

Alistair

>
> > +            /*
> > +             * If size is unknown (0), assume that all bytes
> > +             * from addr to the end of the page will be accessed.
> > +             */
> > +            pmp_size = -(addr | TARGET_PAGE_MASK);
> > +        } else {
> > +            pmp_size = sizeof(target_ulong);
> > +        }
> >      } else {
> >          pmp_size = size;
> >      }
>
> Regards,
> Bin