kvm guests hang after startup

[Kamui]

Binary package hint: kvm

Ubuntu jaunty 9.04 x86
kvm : 1:84+dfsg-0ubuntu12
kernel : 2.6.28-13.45
CPU : Intel E8400 with vmx enabled

Kvm guests (both linux and windows) hang right after grub/init prints "starting up..." (and after the boot menu for windows guests) since the last kernel update : 2.6.28-13.44 -> 2.6.28-13.45.

The problem can be fixed with the following switch in the kvm command line : -cpu qemu64,-nx

I am not sure about what triggered this issue because it happens after a reboot on July 5th and the host was up since July 1st. But the only relevant update i made during this time was the kernel's, so i assumed it was the culprit. I had no issue at all before the reboot.

Here is the IRC log for further details : http://pastebin.com/f5e222c02

[Andreas Hasenack (ahasenack)]

The workaround worked for me.

[Chad Waters (chad)]

I'm seeing this same issue in Karmic. The workaround resolved it.

[William Fernando Merlotto (william-prognus)]

The workaround worked for me to!

I have an Ubuntu jaunty x86
kvm: 84+dfsg-0ubuntu12.3
kernel: 2.6.28-13.45
libvirt-bin: 0.6.4-1ubuntu2~dnjl0~jaunty0

[Alexander Atanasov (aatanasov)]

If you are using libvirt
create /etc/libvirt/qemu/kvm-32
-------------------snip-----------
#!/bin/bash
exec kvm -cpu qemu32,-nx `echo $*`
---------------end-----------------
use qemu64 for 64bit.

Then modify domains to use the wrapper script
virsh edit <domain>
change emulator in device section to:
<emulator>/etc/libvirt/qemu/kvm-32</emulator>

It may be a good idea to ship with a wrapper and a config file to pass extra options to kvm
from libvirt, since it's not easy to pass them now.

[jkyamog (jkyamog)]

Work around works for me to. I just recently upgraded from Intrepid to Jaunty. The kvm guests doesn't really hang its very very slow. After the work around both my guest is back running on normal speed.