The intel-microcode 3.20140913.1 update disables TSX-NI (transactional memory instructions). When a server running libvirt is rebooted with this update, libvirt no longer considers the machine to have a Haswell CPU: # virsh capabilities | grep -A1 '<arch>x86_64' <arch>x86_64</arch> <model>SandyBridge</model> Since Intel disables the feature on their CPUs we shouldn't check for it as well to keep VMs using Haswell working. This was debugged and reported by Chris Boot at http://bugs.debian.org/773189 --- src/cpu/cpu_map.xml | 1 - 1 file changed, 1 deletion(-) diff --git a/src/cpu/cpu_map.xml b/src/cpu/cpu_map.xml index bd9b056..f41dbce 100644 --- a/src/cpu/cpu_map.xml +++ b/src/cpu/cpu_map.xml @@ -507,7 +507,6 @@ <feature name='movbe'/> <feature name='fsgsbase'/> <feature name='bmi1'/> - <feature name='hle'/> <feature name='avx2'/> <feature name='smep'/> <feature name='bmi2'/> -- 2.1.3 -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list