[ovirt-devel] Adding s390 support to oVirt

[Dan Horák]

On Mon, 20 Nov 2017 09:16:48 +0100
Christian Borntraeger <borntraeger at de.ibm.com> wrote:

> 
> 
> On 11/19/2017 09:53 AM, Barak Korren wrote:
> > On 18 November 2017 at 13:14, Barak Korren <bkorren at redhat.com>
> > wrote:
> >> On 16 November 2017 at 19:38, Martin Sivak <msivak at redhat.com>
> >> wrote:
> >>>> Koji is very opinionated about how RPMs and specfiles should
> >>>> look, AFAIK
> >>>
> >>> Actually, koji does not care much. Fedora packaging rules are
> >>> enforced by package reviewers.
> >>>
> >>>> More specifically, Koji usually assumes the starting point for
> >>>> the build process would be a specfile
> >>>
> >>> This is correct though.
> >>>
> >>>> Does fedora have an s390x server associated to it?
> >>>
> >>> They used to have s390 emulators running for that purpose iirc.
> >>
> >> I wonder if someone could provide more information about this. Is
> >> this done via qemu? Or built-in to mock perhaps? It this exists, I
> >> can pave the way to enabling s390x build support on oVirt infra.
> > 
> > There seems to be a 'qemu-system-s390x.x86_64' package avalable for
> > CentOS7 in EPEL, so we might be able to use that to get some
> > emulated s390x Jenkins slaves up. As none of the oVirt infra team
> > members is currently experienced with using this, we would
> > appreciate so help there with:
> 
> qemu s390x emulation does not work with code compiled for z12.
> Would a real virtual machine be what you need?
> The Fedora team DOES have access to a z13. Not sure how much
> resources are available, but can you contact Dan Horak (on cc) if
> there is enough spare capacity.

Christian is right, we have a publicly accessible guest running Fedora
on the Marist College z13 mainframe. It's currently used by ~5 projects
(for example glibc and qemu) as their build and CI host, so adding
another project depends how intensive ovirt's usage would be.


		Dan

> 
> 
> 
> > * Figuring out the right libvirt commands to get an s390x VM running
> > on an x86_64 host.
> > * Figuring out the right way to get an OS image for that VM
> > (Probably using virt-install to run the Fedora installer)
> > * Making sure some JVM is available in those VMs
> > 
> > Once we have that, the rest is quite straight forward.
> > 
> > I've created a Jira ticket to map out, discuss and track the
> > required steps: https://ovirt-jira.atlassian.net/browse/OVIRT-1772
> > 
> > WRT the OS we would use, I can see there are s390x Fedora builds
> > available but no CentOS builds, is there ongoing work to remedy
> > this, we'd rather not have to upgrade our Jenkins slaves every 6
> > months...
> > 
> > As a side note - at this time it seems we would have to manually
> > spin up the s390x VMs with libvirt. It would be awesome if oVirt
> > could get support for foreign architecture emulation at some point.
> > 
>