Re: [Qemu-devel] Network Passthrough configuration!

2012-08-25 Thread Stefan Hajnoczi
On Sat, Aug 25, 2012 at 5:35 AM, GaoYi gaoyi...@gmail.com 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/.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



Re: [Qemu-devel] Network Passthrough configuration!

2012-08-25 Thread GaoYi
  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 stefa...@gmail.com

 On Sat, Aug 25, 2012 at 5:35 AM, GaoYi gaoyi...@gmail.com 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/.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



[Qemu-devel] Network Passthrough configuration!

2012-08-24 Thread GaoYi
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/.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?
   Besides, how to configure the libvirt XML file so that passthrough can
work well from Virsh tools?
   Any response will be appreciated.

Yi