Comment 0 for bug 1853200

When trying to launch an instance in OpenStack Queens on Ubuntu 18.04 with the new kernels, this error happens:

Error: Failed to perform requested operation on instance "david", the instance has an error status: Please try again later [Error: Exceeded maximum number of retries. Exceeded max scheduling attempts 3 for instance bf8dc8b8-37dd-43fa-ace0-90fe18c1d63b. Last exception: the CPU is incompatible with host CPU: Host CPU does not provide required features: hle, rtm].

This seems to be caused by the new kernels disabling the tsx cpu feature as per https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/TAA_MCEPSC_i915

Disabling tsx also disables hle and rtm, and /usr/share/libvirt/cpu_map.xml has hle and rtm configured for many cpu models:

ubuntu@cloud3:~$ grep -e "model name" -e hle -e rtm -e tsx
[...]
    <model name='Haswell'>
      <feature name='hle'/>
      <feature name='rtm'/>
    <model name='Haswell-IBRS'>
      <feature name='hle'/>
      <feature name='rtm'/>
[...]
    <model name='Broadwell'>
      <feature name='hle'/>
      <feature name='rtm'/>
    <model name='Broadwell-IBRS'>
      <feature name='hle'/>
      <feature name='rtm'/>
    <model name='Skylake-Client'>
      <feature name='hle'/>
      <feature name='rtm'/>
    <model name='Skylake-Client-IBRS'>
      <feature name='hle'/>
      <feature name='rtm'/>
    <model name='Skylake-Server'>
      <feature name='hle'/>
      <feature name='rtm'/>
    <model name='Skylake-Server-IBRS'>
      <feature name='hle'/>
      <feature name='rtm'/>
[...]

Additional info:

I see this issue with the following kernel and libvirt versions:

Linux cloud3 4.15.0-70-generic #79-Ubuntu SMP Tue Nov 12 10:36:11 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

ubuntu@cloud3:~$ dpkg -l | grep -e libvirt -e nova
ii libvirt-clients 4.0.0-1ubuntu8.13 amd64 Programs for the libvirt library
ii libvirt-daemon 4.0.0-1ubuntu8.13 amd64 Virtualization daemon
ii libvirt-daemon-driver-storage-rbd 4.0.0-1ubuntu8.13 amd64 Virtualization daemon RBD storage driver
ii libvirt-daemon-system 4.0.0-1ubuntu8.13 amd64 Libvirt daemon configuration files
ii libvirt0:amd64 4.0.0-1ubuntu8.13 amd64 library for interfacing with different virtualization systems
ii nova-common 2:17.0.11-0ubuntu1 all OpenStack Compute - common files
ii nova-compute 2:17.0.11-0ubuntu1 all OpenStack Compute - compute node base
ii nova-compute-kvm 2:17.0.11-0ubuntu1 all OpenStack Compute - compute node (KVM)
ii nova-compute-libvirt 2:17.0.11-0ubuntu1 all OpenStack Compute - compute node libvirt support
ii python-libvirt 4.0.0-1 amd64 libvirt Python bindings
ii python-nova 2:17.0.11-0ubuntu1 all OpenStack Compute Python libraries
ii python-novaclient 2:9.1.1-0ubuntu1 all client library for OpenStack Compute API - Python 2.7

ubuntu@cloud3:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 18.04.3 LTS
Release: 18.04
Codename: bionic