Re: [for-5.2 v4 08/10] spapr: PEF: block migration

[Dr. David Alan Gilbert]

* David Gibson (david@gibson.dropbear.id.au) wrote:
> We haven't yet implemented the fairly involved handshaking that will be
> needed to migrate PEF protected guests.  For now, just use a migration
> blocker so we get a meaningful error if someone attempts this (this is the
> same approach used by AMD SEV).
> 
> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
> ---
>  target/ppc/pef.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/target/ppc/pef.c b/target/ppc/pef.c
> index 53a6af0347..6a50efd580 100644
> --- a/target/ppc/pef.c
> +++ b/target/ppc/pef.c
> @@ -36,6 +36,8 @@ struct PefGuestState {
>      Object parent_obj;
>  };
>  
> +static Error *pef_mig_blocker;
> +
>  static int pef_kvm_init(HostTrustLimitation *gmpo, Error **errp)
>  {
>      if (!kvm_check_extension(kvm_state, KVM_CAP_PPC_SECURE_GUEST)) {
> @@ -52,6 +54,10 @@ static int pef_kvm_init(HostTrustLimitation *gmpo, Error 
> **errp)
>          }
>      }
>  
> +    /* add migration blocker */
> +    error_setg(&pef_mig_blocker, "PEF: Migration is not implemented");
> +    migrate_add_blocker(pef_mig_blocker, &error_abort);
> +

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

You might want that to be &error_fatal rather than error_abort; I think
someone could trigger it just by using --only-migratable together with
your pef device?

(I previously asked whether this would trigger with -cpu host; I hadn't
noticed this was based on the device rather than the CPU flag that said
whether you had the feature)

Dave

>      return 0;
>  }
>  
> -- 
> 2.26.2
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK