[Pkg-libvirt-maintainers] libvirt backport for jessie-backports

[Guido Günther]

Hi Gaudenz,
On Tue, Apr 18, 2017 at 09:59:52AM +0200, Gaudenz Steinlin wrote:
> 
> Hi Guido
> 
> Guido Günther <agx at sigxcpu.org> writes:
> 
> > Hi Gaudenz,
> >
> > Thanks for having a look at backporting libvirt.
> >
> > On Sat, Apr 15, 2017 at 04:25:35PM +0200, Gaudenz Steinlin wrote:
> >> 
> >> Hi
> >> 
> >> I needed a newer libvirt version for jessie and tried to create a
> >> backport. I had to revert  the following two changes to the current version in
> >> testing:
> >
> > Care to share which feature you needed?
> 
> I needed to  use network interfaces with UDP unicast tunnels which is
> only supported starting with 1.2.20:
> http://libvirt.org/formatdomain.html#elementsNICSUDP
> 
> I need this to test some network functions (like LACP) between two VMs.
> AFAIK the UDP tunnel is the only type of interface which absolutely does
> not drop any kind of packet and is stateless (unlike TCP) so that each
> VM can be shut down independently.

That makes sense. 

> >
> >> 
> >> * Enable numad support (because there is no numad in jessie)
> >
> > Sounds sane.
> >
> >> * Drop Disable-tests-affected-by-broken-libxml2.patch (because the fixed
> >>   libxml2 is not in jessie)
> >
> > Jessie has a fixed libxml2 since quiet some time so if there are test
> > failures it be cautions.
> 
> I reverted this change because the build depends from stretch conflict
> with the version currently in jessie.
> 
> I retried with only changeing the build dependency to be satisfiable in
> jessie and you are right that disabling the tests is not necessary. All
> tests pass.

Great!

> 
> >
> >> After this the backport seems to work fine. I also had to upgrade
> >> systemd-sysv to the version in jessie-backports.
> >
> > This is the most worriesome part. I guess you had to do that due to the
> > conflict was done to fix #774237 but having this in jessie forces people
> > to upgrade systemd to the backports version.
> 
> If you think the bug is not severe enough to warannt this, we could also
> relax the dependeny. But IMO depending on something which is also in
> jessie-backports is just fine.
> 
> But more important from a dependencies POV only systemd-sysv is updated.
> All other systemd packages stay at the jessie version. I doubt that this
> actually fixes #774237. Why did you not put a Breaks "systemd (<< 224-1~)"?

TBH I don't remember and the changelog is not helpful either in this regard.

> Removing the Breaks for jessie-backports would not make the backport
> worse than the version currently in jessie which is also affected by
> this bug. So my preference would be for removing this.

Agreed.

> 
> >
> >> What do you think? I would like to have this in jessie-backports. If you
> >> agree I can upload my version or I can send you the git branch I created
> >> and you can build and upload yourself. Or do you think that 3.0.0 is not
> >> suitable for jessie-backports?
> >
> > Building the backport once is not the problem, the question is who is
> > going to maintain it until jessie-lts goes EOL now that stretch is
> > around the corner?
> 
> IMO since stretch is around the corner doing this will not be much
> effort. And I don't think there is any promise that backports will be
> supported for LTS. I would be fine to commit to support this until
> jessie is EOL.

That's great. Thanks a lot for checking all the above! I'm fine with you
doig the upload - I can also grab a git branch from somewhere but that
would rather slow down the process since I won't get around to build
that within the next days.

Cheers,
 -- Guido