[Libguestfs] [PATCH] launch: show hint to resolve authentication failure from libvirt

[Olaf Hering]

On Thu, Oct 11, Daniel P. Berrange wrote:

> Hmm, on Fedora non-root is able to use KVM just fine. If you have a
> new enough libvirt, you should have a 'virt-host-validate' command.
> Can you run that as both root and non-root and provide the output
> for each case.

The issue is that a user is not automatically in the kvm group, which however
does not prevent a successful run of 'LIBGUESTFS_ATTACH_METHOD=appliance
libguestfs-test-tool'.

root at stein-schneider:~ # virt-host-validate
  QEMU: Checking for hardware virtualization                                 : PASS
  QEMU: Checking for device /dev/kvm                                         : PASS
  QEMU: Checking for device /dev/vhost-net                                   : PASS
  QEMU: Checking for device /dev/net/tun                                     : PASS
   LXC: Checking for Linux >= 2.6.26                                         : PASS

olaf at stein-schneider:~> virt-host-validate
  QEMU: Checking for hardware virtualization                                 : PASS
  QEMU: Checking for device /dev/kvm                                         : FAIL (Check that the 'kvm-intel' or 'kvm-amd' modules are loaded & the BIOS has enabled virtualization)
  QEMU: Checking for device /dev/vhost-net                                   : WARN (Load the 'vhost_net' module to improve performance of virtio networking)
  QEMU: Checking for device /dev/net/tun                                     : PASS
   LXC: Checking for Linux >= 2.6.26                                         : PASS
olaf at stein-schneider:~> l /dev/kvm 
crw-rw---- 1 root kvm 10, 232 Okt 11 12:37 /dev/kvm
olaf at stein-schneider:~> id
uid=1000(olaf) gid=100(users) groups=100(users),33(video)

However, adding 'olaf' into group 'kvm' does not help to run
libguestfs-test-tool, its still a 'qemu' guest.


olaf at stein-schneider:~> virsh -c qemu:///session capabilities
<capabilities>

  <host>
    <uuid>30826d35-f748-ac09-3792-1386d0a79891</uuid>
    <cpu>
      <arch>x86_64</arch>
      <model>Nehalem</model>
      <vendor>Intel</vendor>
      <topology sockets='1' cores='4' threads='2'/>
      <feature name='rdtscp'/>
      <feature name='dca'/>
      <feature name='pdcm'/>
      <feature name='xtpr'/>
      <feature name='tm2'/>
      <feature name='est'/>
      <feature name='vmx'/>
      <feature name='ds_cpl'/>
      <feature name='monitor'/>
      <feature name='dtes64'/>
      <feature name='pbe'/>
      <feature name='tm'/>
      <feature name='ht'/>
      <feature name='ss'/>
      <feature name='acpi'/>
      <feature name='ds'/>
      <feature name='vme'/>
    </cpu>
    <power_management>
      <suspend_disk/>
    </power_management>
    <migration_features>
      <live/>
      <uri_transports>
        <uri_transport>tcp</uri_transport>
      </uri_transports>
    </migration_features>
    <topology>
      <cells num='1'>
        <cell id='0'>
          <cpus num='8'>
            <cpu id='0'/>
            <cpu id='1'/>
            <cpu id='2'/>
            <cpu id='3'/>
            <cpu id='4'/>
            <cpu id='5'/>
            <cpu id='6'/>
            <cpu id='7'/>
          </cpus>
        </cell>
      </cells>
    </topology>
    <secmodel>
      <model>none</model>
      <doi>0</doi>
    </secmodel>
  </host>

</capabilities>


Olaf