Description of problem:
after every time migrated, offset value will add about 0.1 second.

Version-Release number of selected component (if applicable):
host info:
# uname -r
2.6.18-266.el5
# rpm -qa|grep kvm
kvm-83-236.el5

guest info:


How reproducible:


Steps to Reproduce:
1.
(1)src host:
/usr/libexec/qemu-kvm -M rhel5.4.4 -rtc-td-hack -usbdevice tablet -no-hpet -drive file=/mnt/rhel5.7-32.raw,if=virtio,boot=on,werror=stop,cache=none,format=raw,media=disk -cpu qemu64 -smp 4,sockets=2,cores=1,threads=2 -m 2G -net nic,macaddr=00:12:24:57:a8:2e,model=virtio,vlan=0 -net tap,script=/etc/qemu-ifup,vlan=0 -uuid `uuidgen` -boot c -balloon none -notify all -rtc-td-hack -no-kvm-pit-reinjection -monitor stdio -vnc :1 
(2)des host:
/usr/libexec/qemu-kvm -M rhel5.4.4 -rtc-td-hack -usbdevice tablet -no-hpet -drive file=/mnt/rhel5.7-32.raw,if=virtio,boot=on,werror=stop,cache=none,format=raw,media=disk -cpu qemu64 -smp 4,sockets=2,cores=1,threads=2 -m 2G -net nic,macaddr=00:12:24:57:a8:2e,model=virtio,vlan=0 -net tap,script=/etc/qemu-ifup,vlan=0 -uuid `uuidgen` -boot c -balloon none -notify all -rtc-td-hack -no-kvm-pit-reinjection -monitor stdio -vnc :1 -incoming tcp:0:5555

2.add option divider=10 lpj=n clocksource=acpi_pm to Guest kernel cmdline 

3. sync two host and guest time before do migrate
  ntpdate -q clock.redhat.com

3. do 11 times ping-pong migration 
  
Actual results:
offset value exceed 1 second

Expected results:
offset value always less then 1 second.

Additional info: