Dear all,

I'm looking for a bit of help with a problematic VM. We have an
hypervisor which has 4 eth ports. 3 are already used, and I wanted to
pass the 4th one directly to a VM (which is fully working without it).

So, I modified the XML accordingly (which matches our hardware), adding:
    <hostdev mode='subsystem' type='pci' managed='yes'>
      <source>
        <address domain='0x0000' bus='0x03' slot='0x00' function='0x3'/>
      </source>
    </hostdev>

I also activated Intel IOMMU in Linux (and rebooted). Then, I issued a
virsh start <domain>.

libvirt is able to fire the VM, but then the OS inside doesn't boot at
all. I tried to go deeper into debugging and it seems that the VM cannot
pass SeaBIOS anymore. It gets stuck in seabios, it seems. No "Booting"
sentence displayed, only version of SeaBIOS, when I watch VNC ouput.
I tried to use <bios useserial='yes'/> with a console to the VM. Nothing
is displayed on the console.

Here are the specs of the machine:
-> Ubuntu 12.04LTS up to date
-> libvirt 0.9.8-2ubuntu17.19
-> kvm 1.0+noroms-0ubuntu14.15
-> seabios 0.6.2-0ubuntu2.1

The ethernet card I try to attach is:
Broadcom Corporation NetXtreme BCM5719 Gigabit Ethernet PCIe
Its PCI ID being: 14e4:1657

What are the possibilities to debug this issue? What are the
possibilities to fix it as well?
Thanks to everyone helping!

With my best regards,