Re: [Qemu-devel] ppc: regression in 2.7.0-rc3 on rfi/rfid/hrfi instructions

[Hervé Poussineau]

Le 25/08/2016 à 07:33, Benjamin Herrenschmidt a écrit :
> On Thu, 2016-08-25 at 11:31 +1000, Benjamin Herrenschmidt wrote:
> > Interesting, the problem is only with 603, not 604. I think I might
> > have broken something with the 603 SW TLB loading stuff which is
> > a bit weird, I'll have a look. Thanks.
>
> This fixes it to some extent... It gets to "press enter to activate
> this console" but from there things don't work properly unless I
> emulate a 604. I suspect there are still issues with the 603 SW
> TLB mode.
>
> --- a/target-ppc/excp_helper.c
> +++ b/target-ppc/excp_helper.c
> @@ -959,8 +959,13 @@ static inline void do_rfi(CPUPPCState *env, target_ulong 
> nip, target_ulong msr)
>  {
>      CPUState *cs = CPU(ppc_env_get_cpu(env));
>
> -    /* MSR:POW cannot be set by any form of rfi */
> -    msr &= ~(1ULL << MSR_POW);
> +    /* These bits cannot be set by RFI on non-BookE systems and so must
> +     * be filtered out. 6xx and 7xxx with SW TLB management will put
> +     * TLB related junk in there among other things.
> +     */
> +    if (env->excp_model &= POWERPC_EXCP_BOOKE) {
> +            msr &= ~(target_ulong)0xf0000;
> +    }
>
>  #if defined(TARGET_PPC64)
>      /* Switching to 32-bit ? Crop the nip */
> @@ -990,7 +995,6 @@ void helper_rfi(CPUPPCState *env)
>      do_rfi(env, env->spr[SPR_SRR0], env->spr[SPR_SRR1] & 0xfffffffful);
>  }
>
> -#define MSR_BOOK3S_MASK
>  #if defined(TARGET_PPC64)
>  void helper_rfid(CPUPPCState *env)
>  {

Fixes: a2e71b28e832346409efc795ecd1f0a2bcb705a3
Reported-by: Hervé Poussineau <address@hidden>
Tested-by: Hervé Poussineau <address@hidden>

For the problem to press enter to "activate this console", this is another 
regression.
However, I was unable to pin-point it to a specific commit (too much 
interwinded regressions)
It was working in 2.6.0 (commit a2e71b28e832346409efc795ecd1f0a2bcb705a3)

Hervé