Bug 698166

Summary: Migration will never end after hot-unplug virtual nic
Product: Red Hat Enterprise Linux 6 Reporter: Min Deng <mdeng>
Component: qemu-kvmAssignee: Alex Williamson <alex.williamson>
Status: CLOSED CURRENTRELEASE QA Contact: Virtualization Bugs <virt-bugs>
Severity: high Docs Contact:
Priority: medium    
Version: 6.1CC: bcao, ehabkost, gcosta, juzhang, michen, mkenneth, shu, tburke, virt-maint
Target Milestone: rc   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-12-08 19:49:51 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:

Description Min Deng 2011-04-20 10:52:41 UTC 
Description of problem:
  Migration will never end after hot-unplug virtual nic.
  The following testing results base on local migration (on the same client)

Version-Release number of selected component (if applicable):
kernel version-
2.6.32-133.el6.x86_64
qemu-kvm version -
qemu-kvm-0.12.1.2-2.158.el6.x86_64
host:AMD
How reproducible:
90%

Steps to Reproduce:
1.boot guest (A) with this command line -

 /usr/libexec/qemu-kvm -M rhel6.1.0 -enable-kvm -m 1024 -smp 2,sockets=2,cores=1,threads=1 -name test -uuid ac0c4b71-6c1a-c864-b844-774ff5663b94 -rtc base=localtime -boot c -drive file=/home/A.qcow2,if=none,id=drive-virtio-disk0,format=qcow2,cache=none -device virtio-blk-pci,bus=pci.0,addr=0x7,drive=drive-virtio-disk0,id=virtio-disk0 -netdev tap,id=hostnet0,vhost=on -device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:a7:95:ab,bus=pci.0,addr=0x3 -netdev tap,id=hostnet1,vhost=on -device virtio-net-pci,netdev=hostnet1,id=net1,mac=52:54:00:a6:53:ea,bus=pci.0,addr=0x4 -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -usb -device usb-tablet,id=input0 -spice port=5910,disable-ticketing -vga qxl -device intel-hda,id=sound0,bus=pci.0,addr=0x5 -device hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x6 -monitor stdio

2.from monitor 
(qemu) netdev_del hostnet0
(qemu) device_del net0

3.boot destination (B) with the following command line -

  /usr/libexec/qemu-kvm -M rhel6.1.0 -enable-kvm -m 1024 -smp 2,sockets=2,cores=1,threads=1 -name test -uuid ac0c4b71-6c1a-c864-b844-774ff5663b94 -rtc base=localtime -boot c -drive file=/home/A.qcow2,if=none,id=drive-virtio-disk0,format=qcow2,cache=none -device virtio-blk-pci,bus=pci.0,addr=0x7,drive=drive-virtio-disk0,id=virtio-disk0 -netdev tap,id=hostnet1,vhost=on -device virtio-net-pci,netdev=hostnet1,id=net1,mac=52:54:00:a6:53:ea,bus=pci.0,addr=0x4 -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -usb -device usb-tablet,id=input0 -spice port=5911,disable-ticketing -vga qxl -device intel-hda,id=sound0,bus=pci.0,addr=0x5 -device hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x6 -monitor stdio -incoming tcp:0:5888

4.In A's monitor -
  (qemu) migrate -d tcp:0:5888

Actual results:
  Please pay attention to the value of 'remaining ram',the value will reduce to 88k/72K/64k.But the migration never end.
  (qemu) info migrate 
Migration status: active
transferred ram: 1198948 kbytes
remaining ram: 15900 kbytes
total ram: 1180040 kbytes
(qemu) info migrate 
Migration status: active
transferred ram: 1253196 kbytes
remaining ram: 11616 kbytes
total ram: 1180040 kbytes
(qemu) info migrate 
Migration status: active
transferred ram: 1266776 kbytes
remaining ram: 64 kbytes
total ram: 1180040 kbytes
(qemu) info migrate 
Migration status: active
transferred ram: 1276808 kbytes
remaining ram: 88 kbytes
total ram: 1180040 kbytes
(qemu) info migrate 
Migration status: active
transferred ram: 1281676 kbytes
remaining ram: 88 kbytes
total ram: 1180040 kbytes
(qemu) info migrate 
Migration status: active
transferred ram: 1284816 kbytes
remaining ram: 88 kbytes
total ram: 1180040 kbytes
(qemu) info migrate 
Migration status: active
transferred ram: 1292208 kbytes
remaining ram: 64 kbytes
total ram: 1180040 kbytes
(qemu) info migrate 
Migration status: active
transferred ram: 1294180 kbytes
remaining ram: 72 kbytes
total ram: 1180040 kbytes
(qemu) info migrate 
Migration status: active
transferred ram: 1296168 kbytes
remaining ram: 72 kbytes
total ram: 1180040 kbytes
(qemu) info migrate 
Migration status: active
transferred ram: 1300608 kbytes
remaining ram: 88 kbytes
total ram: 1180040 kbytes

  


Expected results:
Migration can finished successfully.


Additional info:
Comment 2 Alex Williamson 2011-09-20 19:13:12 UTC 
Does this bug still occur?  If so, does the problem also occur when managing the migration via libvirt?  Does it still happen if vhost is not used?  Does it also happen with an emulated nic (e1000, rtl8139) or just with virtio-net-pci?  Thanks.
Comment 4 Shaolong Hu 2011-09-21 03:25:11 UTC 
Won't hit his problem on qemu-kvm-0.12.1.2-2.192.el6.x86_64.
Comment 6 Alex Williamson 2011-12-08 19:49:51 UTC 
According to comment 4, this seems to be fixed already.  Re-open if this is not the case.