Bug 1303624 - [Alcatel vRAN Project] Provide a mechanism to hotplug memory in non-numa guests
Summary: [Alcatel vRAN Project] Provide a mechanism to hotplug memory in non-numa guests
Keywords:
Status: CLOSED WONTFIX
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: libvirt
Version: 7.3
Hardware: Unspecified
OS: Unspecified
unspecified
unspecified
Target Milestone: rc
: ---
Assignee: Libvirt Maintainers
QA Contact: Virtualization Bugs
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2016-02-01 13:53 UTC by Ahmed El-Khouly
Modified: 2016-02-01 14:04 UTC (History)
2 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2016-02-01 14:04:05 UTC
Target Upstream Version:

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Description Ahmed El-Khouly 2016-02-01 13:53:33 UTC 
Description of problem:
It seems that libvirt only support hotplug of memory for guests that exhibit NUMA topology. The only way to hot plug/unplug memory is using the balloon driver which is not a safe mechanism for cloud environments as guests may not be cooperating or even malicious.


Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1. Set MaxMemory element in XML.
2. Boot Instance
3. Boot fails with libvirt error.

Actual results:


Expected results:


Additional info:
Comment 2 Peter Krempa 2016-02-01 14:04:05 UTC 
For x86, qemu mandates the use of a NUMA node to maintain compatibility with windows guests. As the NUMA node is added by qemu, we have to enforce it so that the XML matches the expected config.

A workaround is to add 1 NUMA node to the domain XML, which will be equivalent to the normal configuration.

For non-x86 guests, use of NUMA is not mandated.
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