So is my command line to start the guest OK? The command line is as:
qemu-img -boot c -hda readhat.img -device pci-assign,host=XX:00.0
Why doesn't the network work?
Yi
2012/8/25 Stefan Hajnoczi <[email protected]>
> On Sat, Aug 25, 2012 at 5:35 AM, GaoYi <[email protected]> wrote:
> > Hi all,
> >
> > I am trying to implement pci passthrough for network card according to
> > this guideline:
> > http://www.linux-kvm.org/page/How_to_assign_devices_with_VT-d_in_KVM.
> > The configuration steps were all ok. However, when I started the guest
> > by:
> > qemu-img -boot c -hda readhat.img -device
> > pci-assign,host=XX:00.0,
> > the network of the guest failed. And the host shell reported: cannot
> read
> > from host /sys/bus/pci/devices/0000.XXX/rom. I am very sure the PCI is
> > rightly selected from commands like "lspci -n". So what is the full
> command
> > line to start a guest with network being OK?
>
> I guess you hit this error message:
>
> pci-assign: Cannot read from host %s. Device option ROM contents are
> probably invalid (check dmesg). Skip option ROM probe with rombar=0
> or load from file with romfile=
>
> This is a warning that the option ROM could not be loaded. It's not a
> fatal error and probably just means you cannot use the PCI NIC's
> network boot ROM (PXE) inside the guest. But the NIC should still
> work once your guest OS is booted.
>
> I don't know if there are other implications but it seems to be a
> non-fatal warning.
>
> > Besides, how to configure the libvirt XML file so that passthrough can
> > work well from Virsh tools?
>
> Try this guide for PCI device assignment with libvirt:
>
> https://access.redhat.com/knowledge/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization_Host_Configuration_and_Guest_Installation_Guide/chap-Virtualization_Host_Configuration_and_Guest_Installation_Guide-PCI_Assignment.html
>
> Stefan
>
