Ugly error spewed when kernel doesn't support virtualisation

[Julian Edwards]

It would be nice if it caught this and presented a nicer error - in particular I just needed to reboot because my kernel was out of date.
=================
2014-01-08 12:58:31,842 INFO Checking for KVM extensions.
2014-01-08 12:58:31,883 INFO Checking for virtualised hardware...
2014-01-08 12:58:31,973 INFO Scanning for unexpected DHCP servers on testing network...
2014-01-08 12:58:35,197 INFO Checking for running proxy instance...
2014-01-08 12:58:35,198 INFO Starting proxy...
2014-01-08 12:58:35,207 INFO Done starting proxy.
2014-01-08 12:58:35,214 INFO Downloading KVM image for series=saucy, arch=amd64...
2014-01-08 13:11:36,328 INFO Done downloading KVM image for series=saucy, arch=amd64.
2014-01-08 13:11:36,740 INFO Creating virtual machine c3dd8de0-7810-11e3-944d-e4115b13819f, arch=amd64...
2014-01-08 13:11:40,400 INFO Killing proxy...
2014-01-08 13:11:40,479 INFO Done killing proxy.
ERROR

======================================================================
ERROR: setUpClass (maastest.main.ConfiguredTestMAAS)
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Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/maastest/cases.py", line 95, in setUpClass
    cls.fixtures.useFixture(cls.machine)
  File "/usr/lib/python2.7/dist-packages/maastest/cases.py", line 46, in useFixture
    super(ClassFixture, self).useFixture(fixture)
  File "/usr/lib/python2.7/dist-packages/fixtures/fixture.py", line 192, in useFixture
    fixture.setUp()
  File "/usr/lib/python2.7/dist-packages/maastest/kvmfixture.py", line 148, in setUp
    self.start()
  File "/usr/lib/python2.7/dist-packages/maastest/kvmfixture.py", line 274, in start
    input=template, check_call=True)
  File "/usr/lib/python2.7/dist-packages/maastest/utils.py", line 70, in run_command
    raise make_exception(args, retcode, stdout, stderr)
Exception: Command 'sudo uvt-kvm create --ssh-public-key-file=/home/ubuntu/.config/maas-test/vm_ssh_id_rsa.pub --unsafe-caching --memory 2047 --disk 20 c3dd8de0-7810-11e3-944d-e4115b13819f arch=amd64 release=saucy --template -' failed (1):

Warning: this CLI is experimental and may change.
wrote ds.img with filesystem=iso9660 and diskformat=raw
libvirt: Domain Config error : unknown OS type hvm
Traceback (most recent call last):
  File "/usr/bin/uvt-kvm", line 597, in <module>
    main(sys.argv[1:])
  File "/usr/bin/uvt-kvm", line 593, in main
    args.func(parser, args)
  File "/usr/bin/uvt-kvm", line 436, in main_create
    unsafe_caching=args.unsafe_caching,
  File "/usr/bin/uvt-kvm", line 321, in create
    domain = conn.defineXML(xml)
  File "/usr/lib/python2.7/dist-packages/libvirt.py", line 2930, in defineXML
    if ret is None:raise libvirtError('virDomainDefineXML() failed', conn=self)
libvirt.libvirtError: unknown OS type hvm

----------------------------------------------------------------------
Ran 0 tests in 785.317s

[Raphaël Badin (rvb)]

I agree that it would be nice explaining the user out to fix this… But is an out of date kernel really the cause of this? I've seen this happen a couple of times and it turned out that running the following command made the problem disappear:
$ sudo service libvirt-bin restart

It might be work poking rbasak about this.