Bug 1574481
| Summary: | Power 9 host should report host capability to support Power 8 VMs with Power 8 hosts in the same cluster | ||
|---|---|---|---|
| Product: | [oVirt] vdsm | Reporter: | Michal Skrivanek <michal.skrivanek> |
| Component: | Core | Assignee: | Dan Kenigsberg <danken> |
| Status: | CLOSED CURRENTRELEASE | QA Contact: | Israel Pinto <ipinto> |
| Severity: | high | Docs Contact: | |
| Priority: | high | ||
| Version: | --- | CC: | abologna, bugs |
| Target Milestone: | ovirt-4.2.5 | Flags: | rule-engine:
ovirt-4.2+
|
| Target Release: | --- | ||
| Hardware: | ppc64le | ||
| OS: | Unspecified | ||
| Whiteboard: | |||
| Fixed In Version: | vdsm-4.20.28-1 | Doc Type: | If docs needed, set a value |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2018-07-31 15:31:19 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | Virt | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | |||
| Bug Blocks: | 1574494 | ||
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Description
Michal Skrivanek
2018-05-03 12:07:57 UTC
This does seem to be caused by libvirt's CPU comparision call (libvirtconnection.compareCPU) - more specifically, we check that the model is libvirt.VIR_CPU_COMPARE_SUPERSET or libvirt.VIR_CPU_COMPARE_IDENTICAL. Is this a specific PVR/CPU model that happens to be incompatible w/ POWER8 or a bug in libvirt? oVirt has switched to the compat=power8 cpu mode that should guarantee at least *some* level of POWER8/POWER9 compat. (In reply to Martin Polednik from comment #1) > This does seem to be caused by libvirt's CPU comparision call > (libvirtconnection.compareCPU) - more specifically, we check that the model > is > > libvirt.VIR_CPU_COMPARE_SUPERSET or > libvirt.VIR_CPU_COMPARE_IDENTICAL. > > Is this a specific PVR/CPU model that happens to be incompatible w/ POWER8 > or a bug in libvirt? oVirt has switched to the compat=power8 cpu mode that > should guarantee at least *some* level of POWER8/POWER9 compat. It seems to work fine here: $ virsh capabilities | grep POWER <model>POWER9</model> $ cat cpu.xml <cpu mode='host-model'> <model>power8</model> </cpu> $ virsh cpu-compare cpu.xml CPU described in cpu.xml is identical to host CPU The support was introduce quite a while ago: commit 5c8c2d1633f3d2500e49132296793fc267648d2b Author: Jiri Denemark <jdenemar> Date: Wed May 17 16:39:16 2017 +0200 cpu_ppc64: Add support for host-model on POWER9 Signed-off-by: Jiri Denemark <jdenemar> v3.4.0-95-g5c8c2d1633 Can you try the steps above on your machine and share the results? Can be tested with 4.2.4 release since it should have been fixed in vdsm v4.20.28 Verify with:
vdsm-4.20.32-1.el7ev.ppc64le
Steps:
Run VM on Power9 host in Power8 cluster.
Results:
VM is up and running
VM xml
virsh -r dumpxml 1 | grep power8
<cpu mode='host-model' check='partial'>
<model fallback='forbid'>power8</model>
Host info:
# virsh -r capabilities | grep POWER
<model>POWER9</model>
PASS
This bugzilla is included in oVirt 4.2.5 release, published on July 30th 2018. Since the problem described in this bug report should be resolved in oVirt 4.2.5 release, it has been closed with a resolution of CURRENT RELEASE. If the solution does not work for you, please open a new bug report. |