Hello Christian,
Unfortunately I have re-installed since the error came up. You are right,
due to my ignorance I originally  installed multiple related virtualization
tools xen qemu, kdm, not being sure which one would work.
The good news is I am prepared to try to reproduce the problem now.  In my
case this would be:

Install Ubuntu 14.04 install libvirt and friends including xen, and upgrade
each OS version until 17.10.

I will go through this procedure tonight if it would be helpful in your
diagnosis.

Peter
--

On Fri, Mar 16, 2018 at 5:25 AM, ChristianEhrhardt <
<email address hidden>> wrote:

> Hi,
> I wonder about the "Resource temporarily unavailable" error in this.
> This could be something consuming all FDs, or multiple libvirts daemons
> starting.
>
> What does "ps axlf | grep libvirtd" show you?
>
> Does /var/run/libvirtd.pid exist and if so what is in there.
> If it is a pid, which process is that?
>
> [1] had a similar case.
>
> For the issue you see with the 4.10 kernel hat is actually a xen library
> (not libvirt).
> libxl_fork.c:353 is from source:xen  ./tools/libxl/libxl_fork.c
>
> 341 static void sigchld_installhandler_core(void) /* idempotent */
> 342 {
> 343     if (sigchld_installed)
> 344         return;
> 345
> 346     sigchld_installed = 1;
> 347
> 348     sigchld_sethandler_raw(sigchld_handler, &sigchld_saved_action);
> 349
> 350     assert(((void)"application must negotiate with libxl about
> SIGCHLD",
> 351             !(sigchld_saved_action.sa_flags & SA_SIGINFO) &&
> 352             (sigchld_saved_action.sa_handler == SIG_DFL ||
> 353              sigchld_saved_action.sa_handler == SIG_IGN)));
> 354 }
>
> Are you driving xen with your libvirt, or is this just the basic
> initialization code?
>
> IMHO that is a known upstream issue:
> https://www.redhat.com/archives/libvir-list/2015-January/msg00868.html
> https://www.redhat.com/archives/libvir-list/2015-November/msg00336.html
> https://bugzilla.redhat.com/show_bug.cgi?id=1278847
>
> Due to Xen + vbox + libvirt not playing together nicely.
>
> I don't know what guests you really drive, but as a last resort workaround
> until one day there is an upstream fix you might disable what you don't
> use, which means either:
> - do not use a xen kernel
> - remove one of /usr/lib/libvirt/connection-driver/libvirt_driver_xen.so
> /usr/lib/libvirt/connection-driver/libvirt_driver_vbox.so (or both if you
> need none)
>   They initialize when they see something they could handle, maybe there
> is a config to avoid loading them but I don't know (the same search
> distance away as you)
>
>
> [1]: https://www.redhat.com/archives/libvirt-users/2012-
> October/msg00146.html
>
> ** Bug watch added: Red Hat Bugzilla #1278847
>    https://bugzilla.redhat.com/show_bug.cgi?id=1278847
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1727138
>
> Title:
>   libvirtd crashed with SIGABRT in __assert_fail_base()
>
> Status in libvirt package in Ubuntu:
>   New
>
> Bug description:
>   During upgrade to 17.10, a couple packages didn't install correctly
>   due to dependencies. This was the first reboot when libvirt failed.
>
>   ProblemType: Crash
>   DistroRelease: Ubuntu 17.10
>   Package: libvirt-daemon 3.6.0-1ubuntu5
>   ProcVersionSignature: Ubuntu 4.13.0-16.19-lowlatency 4.13.4
>   Uname: Linux 4.13.0-16-lowlatency x86_64
>   ApportVersion: 2.20.7-0ubuntu3
>   Architecture: amd64
>   Date: Tue Oct 24 22:34:59 2017
>   ExecutablePath: /usr/sbin/libvirtd
>   InstallationDate: Installed on 2016-02-09 (623 days ago)
>   InstallationMedia: Ubuntu-MATE 15.04 "Vivid Vervet" - Release amd64
> (20150422.1)
>   ProcAttrCurrent: /usr/sbin/libvirtd (enforce)
>   ProcCmdline: placeholder root=UUID=8edb633f-0b5e-4e9b-a0e3-ef6f9b14dcb8
> ro quiet splash
>   ProcEnviron:
>    LANG=en_US.UTF-8
>    PATH=(custom, no user)
>   Signal: 6
>   SourcePackage: libvirt
>   Title: libvirtd crashed with SIGABRT in __assert_fail_base()
>   UpgradeStatus: Upgraded to artful on 2017-10-25 (0 days ago)
>   UserGroups:
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/
> 1727138/+subscriptions
>