[libvirt-users] libvirt reported capabilities doesn't match /proc/cpuinfo while the model does match

[Braiam Peguero]

Hi,

According to virsh capabilities I only have the following cpu features:

    <cpu>
      <arch>x86_64</arch>
      <model>IvyBridge-IBRS</model>
      <vendor>Intel</vendor>
      <microcode version='32'/>
      <topology sockets='1' cores='4' threads='1'/>
      <feature name='ds'/>
      <feature name='acpi'/>
      <feature name='ss'/>
      <feature name='ht'/>
      <feature name='tm'/>
      <feature name='pbe'/>
      <feature name='dtes64'/>
      <feature name='monitor'/>
      <feature name='ds_cpl'/>
      <feature name='vmx'/>
      <feature name='smx'/>
      <feature name='est'/>
      <feature name='tm2'/>
      <feature name='xtpr'/>
      <feature name='pdcm'/>
      <feature name='pcid'/>
      <feature name='osxsave'/>
      <feature name='arat'/>
      <feature name='ssbd'/>
      <feature name='xsaveopt'/>
      <feature name='invtsc'/>
      <pages unit='KiB' size='4'/>
      <pages unit='KiB' size='2048'/>
    </cpu>

Meanwhile, cpuinfo reports the following:

flags        : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe
syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl
xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor
ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic
popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm
cpuid_fault epb pti ssbd ibrs ibpb stibp tpr_shadow vnmi flexpriority
ept vpid fsgsbase smep erms xsaveopt dtherm ida arat pln pts flush_l1d
bugs        : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf

This results on my cpu being detected, if I allow host copy, as AMD chip and
the guest becomes unbearably slow. The model of the host cpu is correct.
I'm using Debian testing/unstable.

Compiled against library: libvirt 4.7.0
Using library: libvirt 4.7.0
Using API: QEMU 4.7.0
Running hypervisor: QEMU 2.12.0

-- 
Braiam