Ubuntu
virt-manager package

Comment 6 for bug 1861643

Revision history for this message

Christian Ehrhardt  (paelzer) wrote on 2020-03-04:

Using the backports of libvirt we have in the Ubuntu Cloud Archive I was upgrading through different versions and comparing the behavior:

Note: Clearing /var/cache/libvirt/qemu/capabilities/ manually to be sure between every test.

Interestingly I used LXD containers to do my test and that seems to have an effect as well.
Whatever container protection/isolation takes place here might be related to this.

Also libvirt probes things from qemu, so the qemu version can be important as well.

#1 Bionic - as-is (libvirt 4.0 qemu 2.11) - Container -> Small List
#2 Bionic + Stein (libvirt 5.0 qemu 2.11) - Container -> Small List
#3 Bionic + Train (libvirt 5.4 qemu 2.11) - Container -> Small List
#4 Bionic + Focal-Binaries (libvirt 6.0 qemu 4.2) - Container -> Small List
#5 Bionic - as-is (libvirt 4.0 qemu 2.11) - on Host -> Big List
#6 Focal - (libvirt 6.0 qemu 4.2) - Container - -> Big List

What .... "§$%&/(!
Two mysteries to solve:
- What might make #4 differ from #6?
- What might make #1 differ from #5?

Small List:
      <model usable='yes'>qemu32</model>
      <model usable='yes'>pentium3</model>
      <model usable='yes'>pentium2</model>
      <model usable='yes'>pentium</model>
      <model usable='yes'>n270</model>
      <model usable='yes'>kvm64</model>
      <model usable='yes'>kvm32</model>
      <model usable='yes'>coreduo</model>
      <model usable='yes'>core2duo</model>
      <model usable='yes'>athlon</model>
      <model usable='yes'>Westmere</model>
      <model usable='yes'>Penryn</model>
      <model usable='yes'>Opteron_G2</model>
      <model usable='yes'>Opteron_G1</model>
      <model usable='yes'>Nehalem</model>
      <model usable='yes'>Conroe</model>
      <model usable='yes'>486</model>

Big List:
      <model usable='yes'>qemu32</model>
      <model usable='yes'>pentium3</model>
      <model usable='yes'>pentium2</model>
      <model usable='yes'>pentium</model>
      <model usable='yes'>n270</model>
      <model usable='yes'>kvm64</model>
      <model usable='yes'>kvm32</model>
      <model usable='yes'>coreduo</model>
      <model usable='yes'>core2duo</model>
      <model usable='yes'>Westmere</model>
      <model usable='yes'>Westmere-IBRS</model>
      <model usable='yes'>SandyBridge</model>
      <model usable='yes'>SandyBridge-IBRS</model>
      <model usable='yes'>Penryn</model>
      <model usable='yes'>Opteron_G1</model>
      <model usable='yes'>Nehalem</model>
      <model usable='yes'>Nehalem-IBRS</model>
      <model usable='yes'>IvyBridge</model>
      <model usable='yes'>IvyBridge-IBRS</model>
      <model usable='yes'>Haswell-noTSX</model>
      <model usable='yes'>Haswell-noTSX-IBRS</model>
      <model usable='yes'>Conroe</model>
      <model usable='yes'>Broadwell-noTSX</model>
      <model usable='yes'>Broadwell-noTSX-IBRS</model>
      <model usable='yes'>486</model>