Re: [PATCH] s390x: pv: Fix diag318 PV fencing

[Halil Pasic <pasic@linux.ibm.com>]

On Thu, 22 Oct 2020 04:23:12 -0400
Janosch Frank <frankja@linux.ibm.com> wrote:

> Diag318 fencing needs to be determined on the current VM PV state and
> not on the state that the VM has when we create the CPU model.
> 
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
> Fixes: fabdada935 ("s390: guest support for diagnose 0x318")
> ---
> 
> If you're sure that this is what you want, then I'll send a v2 of the
> patch set.
> 
> ---
>  target/s390x/cpu_features.c | 5 +++++
>  target/s390x/cpu_features.h | 4 ++++
>  target/s390x/cpu_models.c   | 4 ++++
>  target/s390x/kvm.c          | 3 +--
>  4 files changed, 14 insertions(+), 2 deletions(-)
> 
> diff --git a/target/s390x/cpu_features.c b/target/s390x/cpu_features.c
> index 31ea8df246..42fe0bf4ca 100644
> --- a/target/s390x/cpu_features.c
> +++ b/target/s390x/cpu_features.c
> @@ -14,6 +14,7 @@
>  #include "qemu/osdep.h"
>  #include "qemu/module.h"
>  #include "cpu_features.h"
> +#include "hw/s390x/pv.h"
>  
>  #define DEF_FEAT(_FEAT, _NAME, _TYPE, _BIT, _DESC) \
>      [S390_FEAT_##_FEAT] = {                        \
> @@ -105,6 +106,10 @@ void s390_fill_feat_block(const S390FeatBitmap features, S390FeatType type,
>          }
>          feat = find_next_bit(features, S390_FEAT_MAX, feat + 1);
>      }
> +
> +    if (type == S390_FEAT_TYPE_SCLP_FAC134 && s390_is_pv()) {
> +        clear_be_bit(s390_feat_def(S390_FEAT_DIAG_318)->bit, data);
> +    }
>  }

Sorry, I'm a little rusty with cpu models. Does this affect the outcome
of the corresponding QMP commands?

I would guess it does...

Regards,
Halil