From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54243) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1et8t6-0003UZ-Er for qemu-devel@nongnu.org; Tue, 06 Mar 2018 04:28:01 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1et8t2-0007W2-CL for qemu-devel@nongnu.org; Tue, 06 Mar 2018 04:28:00 -0500 Date: Tue, 6 Mar 2018 10:27:52 +0100 From: Cornelia Huck Message-ID: <20180306102752.168548c7.cohuck@redhat.com> In-Reply-To: References: <1519407778-23095-1-git-send-email-imbrenda@linux.vnet.ibm.com> <1519407778-23095-4-git-send-email-imbrenda@linux.vnet.ibm.com> <90dab7d2-be2a-4ab6-ed08-4ce8cac5664f@de.ibm.com> <20180305162710.70f680ff.cohuck@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [qemu-s390x] [PATCH v4 3/3] s390x/sclp: extend SCLP event masks to 64 bits List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Christian Borntraeger Cc: Claudio Imbrenda , qemu-s390x@nongnu.org, qemu-devel@nongnu.org On Tue, 6 Mar 2018 09:23:23 +0100 Christian Borntraeger wrote: > On 03/05/2018 04:27 PM, Cornelia Huck wrote: > > On Fri, 2 Mar 2018 10:44:46 +0100 > > Christian Borntraeger wrote: > > > >> On 02/23/2018 06:42 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 > >>> --- > >>> hw/s390x/event-facility.c | 56 ++++++++++++++++++++++++++++++--------- > >>> include/hw/s390x/event-facility.h | 2 +- > >>> 2 files changed, 45 insertions(+), 13 deletions(-) > >>> > >>> diff --git a/hw/s390x/event-facility.c b/hw/s390x/event-facility.c > >>> index e04ed9f..c3e39ee 100644 > >>> --- a/hw/s390x/event-facility.c > >>> +++ b/hw/s390x/event-facility.c > >>> @@ -30,7 +30,7 @@ struct SCLPEventFacility { > >>> SysBusDevice parent_obj; > >>> SCLPEventsBus sbus; > >>> /* guest's receive mask */ > >>> - sccb_mask_t receive_mask; > >>> + uint32_t receive_mask_pieces[2]; > >> > >> > >> Before the change, we basically use be32_to_cpu to transfer the byte field into a cpu > >> endianess value. In the end it is actually a bitfield, but for compat we need to keep > >> he reversal. So it will be hard to get this fixed without some kind of ugliness. > > > > Could we also use a compat mask callback/handler for older machines and > > switch to 64 bit handlers for the default case? Probably would be even > > more ugly, though. > > Claudio had a version with a pre/post/load/save handler. Claudio can you repost this > version so that we can have a look what is "less ugly"? > Would that other version be independent of the first two patches (i.e., only replace this patch)? I would like to apply patch 1 as it is a fix, and patch 2 seems uncontroversial as a cleanup.