Thanks for reporting this bug. I won't be able to test this for another week or two (waiting on a license). Would it be possible for you to test with the latest upstream git?
sudo apt-get install git git clone git://git.qemu.org/qemu.git cd qemu ./configure x86_64-softmmu make cd x86_64-softmmu sudo mv /usr/bin/qemu-system-x86 /usr/bin/qemu-system-x86.orig sudo cp x86_64-softmmu /usr/bin/ Then re-test your guest. If that's not possible then please let us know. importance: high status: incomplete ** Changed in: qemu Importance: Undecided => High ** Changed in: qemu Status: New => Incomplete -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1174654 Title: qemu-system-x86_64 takes 100% CPU after host machine resumed from suspend to ram Status in QEMU: Incomplete Bug description: I have Windows XP SP3 inside qemu VM. All works fine in 12.10. But after upgraiding to 13.04 i have to restart the VM each time i resuming my host machine, because qemu process starts to take CPU cycles and OS inside VM is very slow and sluggish. However it's still controllable and could be shutdown by itself. According to the taskmgr any active process takes 99% CPU. It's not stucked on some single process. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1174654/+subscriptions