Bug 1689195

Summary: RFE: report limit on number of SEV guests in domain capabilities XML
Product: Red Hat Enterprise Linux Advanced Virtualization Reporter: Daniel Berrangé <berrange>
Component: libvirtAssignee: Pavel Hrdina <phrdina>
Status: CLOSED DUPLICATE QA Contact: Luyao Huang <lhuang>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 8.0CC: dyuan, eskultet, jsuchane, kchamart, lhuang, xuzhang, yalzhang
Target Milestone: rcKeywords: Triaged
Target Release: 8.1   
Hardware: Unspecified   
OS: Unspecified   
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Last Closed: 2020-10-15 12:55:12 UTC Type: Bug
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 1689202    
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Description Daniel Berrangé 2019-03-15 12:01:07 UTC 
Description of problem:
It was said that when using SEV, there is a limit of 15 guests that are able to use the feature concurrently.

https://www.redhat.com/archives/libvir-list/2019-January/msg00652.html

This kind of limit is important for a mgmt application to know about, so that it can place VMs on hosts which have suitable resource available, but this is not yet exposed anywhere.

It needs to be reported in the libvirt capabilities XML. Probably we would get this information from QEMU via QMP when querying SEV support.

Version-Release number of selected component (if applicable):
libvirt-5.0.0-6.el8

How reproducible:
Always

Steps to Reproduce:
1. Run  'virsh domcapabilities kvm'

Actual results:
SEV feature is reported, but with no mention of the guest limit:

     <domainCapabilities>
          ...
          <features>
            ...
            <sev supported='yes'/>
              ...
            </sev>
          </features>
        </domainCapabilities>

Expected results:
Above XML includes the guest limit
Comment 1 Jaroslav Suchanek 2020-10-15 12:55:12 UTC 
Can be done as part of bug 1689202.

*** This bug has been marked as a duplicate of bug 1689202 ***