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Bug 1285595

Summary: vubr coredumpd during repeatedly load/unload virtio-net driver inside guest.
Product: Red Hat Enterprise Linux 7 Reporter: Qian Guo <qiguo>
Component: qemu-kvm-rhevAssignee: Victor Kaplansky <vkaplans>
Status: CLOSED ERRATA QA Contact: Pei Zhang <pezhang>
Severity: medium Docs Contact:
Priority: medium    
Version: 7.2CC: ailan, juzhang, knoel, michen, mrezanin, victork, virt-maint
Target Milestone: rc   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: qemu-kvm-rhev-2.6.0-1.el7 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2016-11-07 21:38:48 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:
Bug Depends On:    
Bug Blocks: 1288337    

Comment 5 Mike McCune 2016-03-28 23:44:20 UTC 
This bug was accidentally moved from POST to MODIFIED via an error in automation, please see mmccune with any questions
Comment 7 Pei Zhang 2016-09-08 07:17:30 UTC 
Verification:
Versions:
Host:
3.10.0-503.el7.x86_64
qemu-kvm-rhev-2.6.0-18.el7.x86_64

Guest:
3.10.0-503.el7.x86_64

Steps:
1. Launch slirp as background
#　/usr/libexec/qemu-kvm \
-net none \
-net socket,vlan=0,udp=localhost:4444,localaddr=localhost:5555 \
-net user,vlan=0

2. Start vhotuser as server
# ./vhost-user-bridge

3. Boot guest with vhostuser as client
# /usr/libexec/qemu-kvm -enable-kvm -m 4096 -smp 4 \
-object memory-backend-file,id=mem0,size=4096M,mem-path=/dev/hugepages,share=on \
-numa node,nodeid=0,memdev=mem0 \
-mem-prealloc \
-vga std -vnc :10 \
/home/pezhang/rhel7.3.qcow2 \
-chardev socket,id=char0,path=/tmp/vubr.sock \
-device virtio-net-pci,netdev=mynet1,mac=54:52:00:1a:2c:01 \
-netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce \
-monitor stdio \

4. Repeat unload/load virtio_net driver in guest, vhost-user-bridge works well after 16 minutes.
# while true ; do modprobe -r virtio_net ; sleep 0.5 ; modprobe virtio_net; pkill dhclient ; sleep 0.5 ; dhclient eth0; done


So this bug has been fixed well.
Comment 8 Pei Zhang 2016-09-08 07:56:42 UTC 
Also re-verify this bug with vhost-user-bridge of qemu-kvm-rhev-2.6.0-23.el7.src.rpm.  Still works well.

So set this bug to 'VERIFIED' as Comment 7 and Comment 8.
Comment 10 errata-xmlrpc 2016-11-07 21:38:48 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-2016-2673.html