Bug#764477: Cannot connect to VM anymore nor install new one

[Thibaut]

Package: gnome-boxes
Version: 3.14.0-1

After recent updates, I can't see anymore Windows 7 guest OS I used to launch via GNOME Boxes.

And if I try to install a new guest, for instance ubuntu-14.04-desktop-amd64.iso, I get this error message and can't proceed :
(gnome-boxes:26326): Boxes-WARNING **: wizard.vala:459: Failed to create storage pool: invalid connection pointer in virStoragePoolDefineXML

Here is the result I get in a terminal when I key "libvirtd -d" :
libvirtd: error: Unable to obtain pidfile. Check /var/log/messages or run without --daemon for more info.

And here is the result I get in a terminal when I key "gnome-boxes --checks" :
(gnome-boxes:26025): Boxes-WARNING **: util-app.vala:226: Failed to execute: virsh capabilities
(gnome-boxes:26025): Boxes-WARNING **: util-app.vala:206: Failed to execute child process "restorecon" (No such file or directory)
• The CPU is capable of virtualization: yes
• The KVM module is loaded: yes
• Libvirt KVM guest available: no
• Boxes storage pool available: no
    Could not get 'gnome-boxes' storage pool information from libvirt. Make sure 'virsh -c qemu:///session pool-dumpxml gnome-boxes' is working.
• The SELinux context is default: no

On that topic I've found debian report #731668 but it's quite older. See also that Red Hat bug report [1] and that ArchLinux one [2]

My configuration is :
Linux debian 3.16-2-amd64 #1 SMP Debian 3.16.3-2 (2014-09-20) x86_64 GNU/Linux
libc6 2.19-11
libvirt0 1.2.8-3

Thanks !

[1] https://bugzilla.redhat.com/show_bug.cgi?id=1140761
[2] https://bugs.archlinux.org/task/42119.