Bug 726020 – Fix memleaks in all virtio devices

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Bug 726020 - Fix memleaks in all virtio devices

Summary:	Fix memleaks in all virtio devices

Status:	CLOSED ERRATA

Aliases:	None

Product:	Red Hat Enterprise Linux 6
Classification:	Red Hat
Component:	qemu-kvm (Show other bugs)
Sub Component:
Version:	6.2
Hardware:	Unspecified Unspecified

Priority	unspecified Severity unspecified
Target Milestone:	rc
Target Release:	---
Assigned To:	Amit Shah
QA Contact:	Virtualization Bugs
Docs Contact:

URL:
Whiteboard:
Keywords:

Depends On:
Blocks:
	Show dependency tree / graph

Reported:	2011-07-27 06:31 EDT by Amit Shah
Modified:	2013-01-09 19:09 EST (History)
CC List:	5 users (show)

See Also:
Fixed In Version:	qemu-kvm-0.12.1.2-2.179.el6
Doc Type:	Bug Fix
Doc Text:
Story Points:	---
Clone Of:
Environment:
Last Closed:	2011-12-06 10:54:53 EST
Type:	---
Regression:	---
Mount Type:	---
Documentation:	---
CRM:
Verified Versions:
Category:	---
oVirt Team:	---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---

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Add an attachment (proposed patch, testcase, etc.)

External Trackers
Tracker	ID	Priority	Status	Summary	Last Updated
Red Hat Product Errata	RHSA-2011:1531	normal	SHIPPED_LIVE	Moderate: qemu-kvm security, bug fix, and enhancement update	2011-12-05 20:23:30 EST

Groups: None (edit)

Description Amit Shah 2011-07-27 06:31:11 EDT

Description of problem:

virtio_cleanup() is supposed to reverse the mallocs in virtio_common_init().  However, it doesn't free up RAM allocated for device structures (VirtIOBlock, VirtIOBalloon, VirtIOSerial, VirtIONet) which embed the VirtIODevice struct.

This means all the virtio devices leak memory on unplug or qemu exit.

Comment 7 Shaolong Hu 2011-09-09 06:16:03 EDT

Since there is also memory leak in virtio-blk and virtio-balloon which is fixed on qemu-kvm-0.12.1.2-2.179.el6, choose virtio-net to verify this bug.


Steps to reproduce and verify:
------------------------------------
1.Disable as more services as possible in level 3 and init 3:
[root@localhost ~]# ls /etc/rc.d/rc3.d/
K01libvirt-guests  K05atd        K30postfix         K50snmpd       K74acpid      K75quota_nld  K83rpcidmapd       K85messagebus   K88iscsi    K92ip6tables     S05cgconfig
K01smartd          K10psacct     K30spice-vdagentd  K50snmptrapd   K74haldaemon  K75udev-post  K84NetworkManager  K86cgred        K88rsyslog  K92iptables      S13rpcbind
K02avahi-daemon    K10saslauthd  K46radvd           K60crond       K74ntpd       K80kdump      K84wpa_supplicant  K87irqbalance   K89iscsid   K99cpuspeed      S84ksm
K02rhsmcertd       K16abrtd      K50dnsmasq         K60nfs         K75netfs      K83nfslock    K85ebtables        K87restorecond  K89rdisc    K99lvm2-monitor  S85ksmtuned
K03rhnsd           K25sshd       K50netconsole      K69rpcsvcgssd  K75ntpdate    K83rpcgssd    K85mdmonitor       K88auditd       K90network  K99sysstat       S99local

2.Make sure top suggests there are not other memory consuming processes:
  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+ COMMAND            
    1 root      20   0 19204 1492 1208 S  0.0  0.0   0:00.62 init
    2 root      20   0     0    0    0 S  0.0  0.0   0:00.00 kthreadd
    3 root      RT   0     0    0    0 S  0.0  0.0   0:00.01 migration/0
    4 root      20   0     0    0    0 S  0.0  0.0   0:00.00 ksoftirqd/0
    5 root      RT   0     0    0    0 S  0.0  0.0   0:00.00 migration/0

3.Boot guest, do 300 times virtio-net-pci device hotplug/unplug, use "free -m" when:
  1) before start qemu
  2) before hotplug/unplug
  3) after hotplug/unplug
  4) after exit qemu
  each time before "free -m", do "echo 3 > /proc/sys/vm/drop_caches" first.


Actual results:
---------------------
reproduced on qemu-kvm-0.12.1.2-2.178.el6.x86_64:

used    free    buffers/cached             
183     7279          0/7             <---before start qemu
746     6716          0/9             <---start qemu
761     6701          0/9             <---after hotplug/unplug 300 times
183     7278          0/7             <---after exit qemu

verified on qemu-kvm-0.12.1.2-2.184.el6.x86_64:

used    free    buffers/cached             
182     7279          0/6             <---before start qemu
753     6709          0/9             <---start qemu
758     6704          0/9             <---after hotplug/unplug 300 times
183     7279          0/6             <---after exit qemu

Conclusion:
---------------
After hotplug/unplug 300 times, but not exit yet, on qemu-kvm 178, system free memory reduces 15M, on 184, reduces only 5M, based on results above, the patch works well, verified.

Comment 9 errata-xmlrpc 2011-12-06 10:54:53 EST

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.

http://rhn.redhat.com/errata/RHSA-2011-1531.html

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