[ovirt-users] Nested KVM - vdsm-hook-nestedvt

Mon Jan 4 13:56:04 UTC 2016


----- Original Message -----
> From: "Martin Polednik" <mpolednik at redhat.com>
> To: wdh at dds.nl
> Cc: "users" <users at ovirt.org>, "Martin Polednik" <mpolednik at redhat.com>
> Sent: Monday, January 4, 2016 2:52:03 PM
> Subject: Re: [ovirt-users] Nested KVM - vdsm-hook-nestedvt
> 
> On 04/01/16 14:38 +0100, wdh at dds.nl wrote:
> >Hi all,
> >
> >OK, it seems I am confused. Nested KVM is NOT the same as fake KVM....
> >
> >If so, I installed vdsm-hook-nestedvt on the hypervisor (only). Trying
> >to run ovirt-Node on a VM it complains there 's no virtualization,
> >despite the kvm_amd module is loaded with nested=1
> >
> >How to enable nested-kvm for oVirt 3.6?
> 
> First, make sure that you're enabling the nested feature for amd (just
> noticed that the example used intel). Please show us the output of
> 
> # cat /sys/module/kvm_intel/parameters/nested

and sorry, did the same mistake again - use

# cat /sys/module/kvm_amd/parameters/nested

> on the host (physical machine), lscpu inside the VM and VM XML - use
> 
> # virsh -r list
> # virsh -r dumpxml {machine_id found in the list}
> 
> Thanks,
> mpolednik
> 
> >Winny
> >
> >
> >Martin Polednik schreef op 04-01-2016 13:29:
> >>On 04/01/16 09:52 +0100, Simone Tiraboschi wrote:
> >>>On Fri, Jan 1, 2016 at 3:32 PM, Winfried de Heiden <wdh at dds.nl> wrote:
> >>>
> >>>>Hi all and happy new year!
> >>>>
> >>>>I'm running oVirt 3.6 on EL7.
> >>>>
> >>>>In order to test nested-kvm I installed vdsm-hook-nestedvt on the
> >>>>hypervisor and put "fake_kvm_support = true" in /etc/vdsm/vdsm.conf.
> >>>
> >>>
> >>>
> >>>
> >>>fake_kvm_support is just for developing purposes and it's not
> >>>needed as it
> >>>prevent guests to run.
> >>
> >>Not really true - fake_kvm_support enables QEMU emulation instead of
> >>hardware virtualization (e.g. VT-x) instructions. It is also quite
> >>broken in it's current state and fix is pending in cpuinfo branch at
> >>gerrit.
> >>
> >>I don't really understand the reason why fake_kvm would be used in
> >>this case as AMD-v is enabled according to svm flag present -
> >>following instructions should be correct for getting the flag passed
> >>to the VMs.
> >>
> >>>Please check to understand if nested support is enabled on your host:
> >>>/sys/module/kvm_intel/parameters/nested
> >>>
> >>>if not
> >>>  echo "options kvm-intel nested=1" > /etc/modprobe.d/kvm-intel.conf
> >>>and reload the module
> >>
> >>>Than install vdsm-hook-nestedvt on your hosts.
> >>>If you want also to use the network on your L2 guest please
> >>>install and
> >>>configure also macspoof vdsm hook on your physical hosts otherwise
> >>>all the
> >>>traffic to/from your L2 guests will be dropped.
> >>>https://github.com/oVirt/vdsm/tree/master/vdsm_hooks/macspoof
> >>>
> >>>
> >>>
> >>>
> >>>>However, afterwards the hypervisor host cannot connect to the ovirt
> >>>>Manager, on ovirt Manager the engine.log will tell:
> >>>>
> >>>>2016-01-01 15:21:42,105 WARN
> >>>>[org.ovirt.engine.core.dal.dbbroker.auditloghandling.AuditLogDirector]
> >>>>(DefaultQuartzScheduler_Worker-76) [71d1638c] Correlation ID:
> >>>>29daf92c,
> >>>>Call Stack: null, Custom Event ID: -1, Message: Host bigvirt moved to
> >>>>Non-Operational state as host does not meet the cluster's minimum CPU
> >>>>level. Missing CPU features : model_Opteron_G3
> >>>>
> >>>>After removing the option all works well again, but I'ḿ lacking
> >>>>the nested
> >>>>kvm option :( Is nested kvm only supported on a limited cpu's??
> >>>>
> >>>>Winny
> >>>>
> >>>>Information from /proc/cpuinfo:
> >>>>
> >>>>processor       : 0
> >>>>vendor_id       : AuthenticAMD
> >>>>cpu family      : 16
> >>>>model           : 10
> >>>>model name      : AMD Phenom(tm) II X6 1055T Processor
> >>>>stepping        : 0
> >>>>microcode       : 0x10000bf
> >>>>cpu MHz         : 2800.000
> >>>>cache size      : 512 KB
> >>>>physical id     : 0
> >>>>siblings        : 6
> >>>>core id         : 0
> >>>>cpu cores       : 6
> >>>>apicid          : 0
> >>>>initial apicid  : 0
> >>>>fpu             : yes
> >>>>fpu_exception   : yes
> >>>>cpuid level     : 6
> >>>>wp              : yes
> >>>>flags           : fpu vme de pse tsc msr pae mce cx8 apic sep
> >>>>mtrr pge mca
> >>>>cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext
> >>>>fxsr_opt
> >>>>pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc rep_good nopl
> >>>>nonstop_tsc
> >>>>extd_apicid aperfmperf pni monitor cx16 popcnt lahf_lm cmp_legacy svm
> >>>>extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs
> >>>>skinit wdt
> >>>>cpb hw_pstate npt lbrv svm_lock nrip_save pausefilter
> >>>>bogomips        : 5625.54
> >>>>TLB size        : 1024 4K pages
> >>>>clflush size    : 64
> >>>>cache_alignment : 64
> >>>>address sizes   : 48 bits physical, 48 bits virtual
> >>>>power management: ts ttp tm stc 100mhzsteps hwpstate cpb
> >>>>
> >>>>_______________________________________________
> >>>>Users mailing list
> >>>>Users at ovirt.org
> >>>>http://lists.ovirt.org/mailman/listinfo/users
> >>>>
> >>
> >>>_______________________________________________
> >>>Users mailing list
> >>>Users at ovirt.org
> >>>http://lists.ovirt.org/mailman/listinfo/users
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