Bug 1167765

Summary:	qemu-kvm-rhev process quit when hotplugging memory size overcommit host memory
Product:	Red Hat Enterprise Linux 7	Reporter:	FuXiangChun <xfu>
Component:	qemu-kvm-rhev	Assignee:	Igor Mammedov <imammedo>
Status:	CLOSED ERRATA	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	7.1	CC:	hhuang, huding, juzhang, michen, mrezanin, virt-maint
Target Milestone:	rc
Target Release:	---
Hardware:	x86_64
OS:	Linux
Whiteboard:
Fixed In Version:	qemu 2.3	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2015-12-04 16:21:57 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description FuXiangChun 2014-11-25 11:32:37 UTC

Description of problem:
Example: host memory size 8G. hotplug 14G size memory to qemu-kvm. 

result:
(qemu) object_add memory-backend-ram,id=mem1,size=15G
Cannot set up guest memory 'mem1': Cannot allocate memory

From QE pov. qemu-kvm should prevent this operation(As overcommit). and print a friendly information.  At least, qemu-kvm process shouldn't quit.  I am not sure upstream tool if have resolved this issue.  If need.  I will test it with virsh.

Version-Release number of selected component (if applicable):
qemu-kvm-rhev-2.1.2-13.el7.x86_64
3.10.0-208.el7.x86_64

How reproducible:
100％

Steps to Reproduce:
1./usr/libexec/qemu-kvm -M pc -enable-kvm -m 4G,slots=4,maxmem=80G -monitor stdio

2.(qemu) object_add memory-backend-ram,id=mem1,size=14G
3.

Actual results:
qemu-kvm-rhev process quit
Cannot set up guest memory 'mem1': Cannot allocate memory

Expected results:


Additional info:

Comment 2 Igor Mammedov 2015-02-12 12:53:45 UTC

fixed upstream, please retest when 7.2 build is available

Comment 3 Miroslav Rezanina 2015-06-18 06:40:22 UTC

Moving to modified state as it is not TestOnly.

Comment 5 Lin Chen 2015-06-23 07:44:18 UTC

reproduce:
host kernel:3.10.0-267.el7.x86_64
host qemu:  qemu-kvm-rhev-2.1.2-21.el7.x86_64

QE retested this bug on the above environment,then got the same result.
So, the bug is reproduced on the above environment.


verify:
host kernel:3.10.0-267.el7.x86_64
host qemu:  qemu-kvm-rhev-2.3.0-4.el7.x86_64

QE retested this bug on the above environment. After hot-plugging memory size overcommit host memory, qemu-kvm process didn't quit and printed a friendly error info.
So, the bug fixed.

Comment 6 huiqingding 2015-06-24 03:44:28 UTC

Based on Comment 5, set this bug to VERIFIED.

Best regards,
Huiqing

Comment 8 errata-xmlrpc 2015-12-04 16:21:57 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2015-2546.html