[libvirt-users] Need help debugging virtio net issue

This is what I use for creating the VM sudo virt-install -n myvm -r 2048 --vcpus=1 --accelerate -v -w bridge:br0,model=virtio --nographics -m 54:52:00:01:bb:8d --disk path=/storage_pool/myvm.raw,size=20,bus=virtio --pxe It used to work fine, but now it get stuck trying to do pxeboot/kickstart. Here's what I see when trying to debug the pxeboot/kickstart process: * Querying DHCP server for IP address went through fine * vmlinuz.CentOS5-5.5-x86_64 was downloaded successfully * initrd.img.CentOS5-5.5-x86_64 started to get transferred, but then stopped. It looks like the VM's network interface just crashed (can't even ping the VM anymore) If I don't use virtio for networking, then everything went through fine. What's strange that is virtio used to work fine. I ran out of ideas/ways to debug this issue. Any has any idea? Here's more info on my system: Host: * Scientific Linux 6, kernel version: 2.6.32-71.el6.x86_64 * libvirt: 0.8.1-27 * qemu-kvm: 0.12.1.2-2.113 Guest: * Scientific Linux 6, kernel version: 2.6.32-71.el6.x86_64