Re: [Qemu-devel] [PATCH] target-sparc: fix register corruption in ldstub if there is no write permission

[Mark Cave-Ayland]

On 24/06/16 16:58, Richard Henderson wrote:

> On 06/24/2016 05:34 AM, Artyom Tarasenko wrote:
> > Signed-off-by: Artyom Tarasenko <address@hidden>
> > ---
> >  target-sparc/translate.c | 5 ++++-
> >  1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/target-sparc/translate.c b/target-sparc/translate.c
> > index 5111cf0..065326c 100644
> > --- a/target-sparc/translate.c
> > +++ b/target-sparc/translate.c
> > @@ -5187,12 +5187,15 @@ printf("ops, illegal rdhpr\n");
> >                  case 0xd:       /* ldstub -- XXX: should be
> > atomically */
> >                      {
> >                          TCGv r_const;
> > +                        TCGv tmp = tcg_temp_new();
> >
> >                          gen_address_mask(dc, cpu_addr);
> > -                        tcg_gen_qemu_ld8u(cpu_val, cpu_addr,
> > dc->mem_idx);
> > +                        tcg_gen_qemu_ld8u(tmp, cpu_addr, dc->mem_idx);
> >                          r_const = tcg_const_tl(0xff);
> >                          tcg_gen_qemu_st8(r_const, cpu_addr,
> > dc->mem_idx);
> > +                        tcg_gen_mov_tl(cpu_val, tmp);
> >                          tcg_temp_free(r_const);
> > +                        tcg_temp_free(tmp);
>
> ldstub_asi has the same problem on mainline.
>
> It looks like I fixed that one on my sparc branch though.
>
>
> r~

In that case would it make sense to prepend this patch to a v4 respin of 
your latest SPARC patchset (as tested by Artyom)?


ATB,

Mark.