Re: [Qemu-devel] [PATCH v5 1/1] s390x/sclp: extend SCLP event masks to 64 bits

[Christian Borntraeger]

On 03/07/2018 04:10 PM, Claudio Imbrenda wrote:
> Extend the SCLP event masks to 64 bits.
> 
> Notice that using any of the new bits results in a state that cannot be
> migrated to an older version.
> 
> Signed-off-by: Claudio Imbrenda <address@hidden>
> ---
>  hw/s390x/event-facility.c         | 49 
> ++++++++++++++++++++++++++++++++-------
>  include/hw/s390x/event-facility.h |  2 +-
>  2 files changed, 41 insertions(+), 10 deletions(-)
> 
> diff --git a/hw/s390x/event-facility.c b/hw/s390x/event-facility.c
> index e04ed9f..c166e0a 100644
> --- a/hw/s390x/event-facility.c
> +++ b/hw/s390x/event-facility.c
> @@ -30,7 +30,10 @@ struct SCLPEventFacility {
>      SysBusDevice parent_obj;
>      SCLPEventsBus sbus;
>      /* guest's receive mask */
> -    sccb_mask_t receive_mask;
> +    union {
> +        uint32_t receive_mask_pieces[2];
> +        sccb_mask_t receive_mask;
> +    };

Would it work to make sccb_mask_t a union instead?