[Users] Nested virtualization with Opteron 2nd generation and oVirt 3.1 possible?

[Gianluca Cecchi]

Hello,
I have 2 physical servers with Opteron 2nd gen cpu.
There is CentOS 6.3 installed and some VM already configured on them.
Their /proc/cpuinfo contains
...
model name : Dual-Core AMD Opteron(tm) Processor 8222
...

kvm_amd kernel module is loaded with its default enabled nested option

# systool -m kvm_amd -v
Module = "kvm_amd"

  Attributes:
    initstate           = "live"
    refcnt              = "15"
    srcversion          = "43D8067144E7D8B0D53D46E"

  Parameters:
    nested              = "1"
    npt                 = "1"
...

I already configured a fedora 17 VM as a oVirt 3.1 Engine

I'm trying to configure another VM as oVirt 3.1 node with
ovirt-node-iso-2.5.5-0.1.fc17.iso
It seems I'm not able to configure so that ovirt install doesn't complain.

After some attempts, I tried this in my vm.xml for the cpu:
  <cpu mode='custom' match='exact'>
    <model fallback='allow'>athlon</model>
    <vendor>AMD</vendor>
    <feature policy='require' name='pni'/>
    <feature policy='require' name='rdtscp'/>
    <feature policy='force' name='svm'/>
    <feature policy='require' name='clflush'/>
    <feature policy='require' name='syscall'/>
    <feature policy='require' name='lm'/>
    <feature policy='require' name='cr8legacy'/>
    <feature policy='require' name='ht'/>
    <feature policy='require' name='lahf_lm'/>
    <feature policy='require' name='fxsr_opt'/>
    <feature policy='require' name='cx16'/>
    <feature policy='require' name='extapic'/>
    <feature policy='require' name='mca'/>
    <feature policy='require' name='cmp_legacy'/>
  </cpu>

Inside node /proc/cpuinfo becomes
processor : 3
vendor_id : AuthenticAMD
cpu family : 6
model : 2
model name : QEMU Virtual CPU version 0.12.1
stepping : 3
microcode : 0x1000065
cpu MHz : 3013.706
cache size : 512 KB
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat
pse36 clflush mmx fxsr sse sse2 syscall mmxext fxsr_opt lm nopl pni
cx16 hypervisor lahf_lm cmp_legacy cr8_legacy
bogomips : 6027.41
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management:

2 questions:

1) Is there any combination in xml file to give to my VM so that oVirt
doesn't complain about missing hardware virtualization with this
processor?

2) suppose 1) is not possible in my case and I still want to test the
interface and try some config operations to see for example the
differences with RHEV 3.0, how can I do?
At the moment this complaint about hw virtualization prevents me to
activate the node.

I get
Installing Host f17ovn01. Step: RHEV_INSTALL.
Host f17ovn01 was successfully approved.
Host f17ovn01 running without virtualization hardware acceleration
Detected new Host f17ovn01. Host state was set to Non Operational.
Host f17ovn01 moved to Non-Operational state.
Host f17ovn01 moved to Non-Operational state as host does not meet the
cluster's minimum CPU level. Missing CPU features : CpuFlags

Can I lower the requirements to be able to operate without hw
virtualization in 3.1?

Thanks in advance,
Gianluca