problems with pci passthrough of nic and a DL380G6

problems with pci passthrough of nic and a DL380G6

[David S. Ahern]

Are the instructions for passing a device at:

http://www.linux-kvm.org/page/How_to_assign_devices_with_VT-d_in_KVM

supposed to work for passing one of four onboard nics to a guest? I ask
because not only did it not work, it made my server a very unhappy camper.

Server:  HP DL380 G6, 1 E5540, 6 GB RAM (3x2), latest BIOS
         SMT enabled, VT-d2 enabled

Host OS: Fedora core 9 OS, kvm.git 66b0aed4a9e15..., pxe booted

Device is last of the four on-board nics (the host is using the first
one). Commands:

modprobe pci-stub

echo "14e4 1639" > /sys/bus/pci/drivers/pci-stub/new_id
echo "0000:03:00.1" > '/sys/bus/pci/devices/0000:03:00.1/driver/unbind'
echo "0000:03:00.1" > /sys/bus/pci/drivers/pci-stub/bind

Those commands worked fine. At this point I tried to mount the 4th
logical disk (host OS is run via pxe and automounting of drives is not
setup) and it failed. Since that disk holds the guest I wanted to run, I
decided to reboot and start fresh. During reboot the server hung after a
few BIOS initialization screens but before the PXE attempt. There was a
1 line message on the screen about an unknown NMI.

The IML for the server shows a couple of critical errors - description
is "Unknown Event (Class 6, Code 4). A second reboot attempt hung at the
same place. I had to disable VT-d2 in the BIOS to get it to come back.

Any ideas?

david

Re: problems with pci passthrough of nic and a DL380G6

[Alex Williamson]

On Mon, 2009-05-11 at 02:09 +0000, David S. Ahern wrote:
> Are the instructions for passing a device at:
> 
> http://www.linux-kvm.org/page/How_to_assign_devices_with_VT-d_in_KVM
> 
> supposed to work for passing one of four onboard nics to a guest? I ask
> because not only did it not work, it made my server a very unhappy camper.
> 
> Server:  HP DL380 G6, 1 E5540, 6 GB RAM (3x2), latest BIOS
>          SMT enabled, VT-d2 enabled

Hi David,

There are some issues with the DMAR table which describes the VT-d
configuration to the host in the initial BIOS release for these systems.
I've been working with our BIOS developers to correct this and I'm
hopeful that next BIOS maintenance release will be more usable for
device passthrough.  Thanks,

Alex