I'm running into some issues with the Openelec VM, and I'm wondering if it's vt-d related. I am running dual Xeon E5420's (http://ark.intel.com/products/33927) in an Asus DSEB-DG/SAS motherboard (https://www.asus.com/Commercial-Servers-Workstations/DSEBDGSAS/). The issue I'm having is that the GPU passthrough doesn't get anything on the display. The motherboard supports VT-D, and it's enabled via BIOS, however the CPU doesn't list VT-d on the Ark site, so I am not sure if it supports it or not. I have assume by the issues I'm having that it likely doesn't, but I'm looking for confirmation, or a way I can verify vt-d compatibility.

For that generation of Xeons, vt-d wasn't supported in the CPU ... it was supported by the chipset and motherboard.    I can't find it mentioned in the specifications for that board, but if it's shown in the BIOS I'd assume that means it's supported.

 

Unfortunately, I'm not aware of any simple test utility to confirm vt-d is working ... and there ARE some graphics boards that have problem with this.    You might try to pass through some other I/O device (SATA controller; USB port; etc.) to see if pass-through is working with those ... if so, that would at least confirm vt-d's working.

 

 

 

Good idea, I'll play with some other devices to see if I can get any results. I wasn't sure if the BIOS setting would be present regardless of CPU, but it's definitely there and definitely enabled so I'm still hopeful...

so I ran a quick test on another VM (Windows 8.1), passing through a couple USB devices without issue. Is it safe to say vt-d is operational? If so, then than narrows down my video issues with Openelec somewhat, though I'm still at a loss as to why I don't get any video output.

If the CPU doesn't support vt-d you can't pass through your graphics card. Both motherboard and CPU must support it.

On the other hand you don't need vt-d for USB pass through.

If you click info on the webgui I guess iommu says disabled, right?

Actually, it says enabled:

 

 

Regardless, I'm going to assume that the issues are due to the CPU, as I don't expect it supports VT-d based on it's original release date. Oh well.

Hmm, that's interesting.  Have you tried having a second gpu installed (in addition to the first)?  Have you tried creating a VM and passing through an alternative device like just a sound card, then using VNC to connect and see if the secondary device shows up properly?

 

If IOMMU is showing up on the info panel, you should be OK to assign devices, but graphics assignment can be more tricky and require additional quirks to make it work, especially with older hardware.

I'll give a few more things a try and see where I end up. I'll post back with the results.

So it turns out Unraid doesn't like working with GT 730 video cards, because that was the culprit. I swapped it for an AMD Radeon and it fired right up!

 

Also, since I searched high and low about the Xeon 5420 and vt-d support, let this be confirmation that it does work just fine assuming your chipset supports it!

 

This makes me very happy, as I have 2 identical systems in my rack and I was really hoping to virutalize all my HTPC's into one of them. If only the Unraid second key sale will still on... 

So it turns out Unraid doesn't like working with GT 730 video cards, because that was the culprit. I swapped it for an AMD Radeon and it fired right up!

 

Also, since I searched high and low about the Xeon 5420 and vt-d support, let this be confirmation that it does work just fine assuming your chipset supports it!

 

This makes me very happy, as I have 2 identical systems in my rack and I was really hoping to virutalize all my HTPC's into one of them. If only the Unraid second key sale will still on... 

You have two servers in a rack with xeon grade hardware and you're complaining about the lack of a second key promo?!?!  Man...tough crowd...

... If the CPU doesn't support vt-d you can't pass through your graphics card. Both motherboard and CPU must support it.

 

Not true with the older generation of Xeons => vt-d was a chipset feature, NOT a CPU feature.

 

So it turns out Unraid doesn't like working with GT 730 video cards, because that was the culprit. I swapped it for an AMD Radeon and it fired right up!

 

Also, since I searched high and low about the Xeon 5420 and vt-d support, let this be confirmation that it does work just fine assuming your chipset supports it!

 

This makes me very happy, as I have 2 identical systems in my rack and I was really hoping to virutalize all my HTPC's into one of them. If only the Unraid second key sale will still on... 

You have two servers in a rack with xeon grade hardware and you're complaining about the lack of a second key promo?!?!  Man...tough crowd...

 

touché

... If the CPU doesn't support vt-d you can't pass through your graphics card. Both motherboard and CPU must support it.

 

Not true with the older generation of Xeons => vt-d was a chipset feature, NOT a CPU feature.

That I was not aware of. Good for the op that I was wrong 

So it turns out Unraid doesn't like working with GT 730 video cards, because that was the culprit. I swapped it for an AMD Radeon and it fired right up!

 

Also, since I searched high and low about the Xeon 5420 and vt-d support, let this be confirmation that it does work just fine assuming your chipset supports it!

Good to know that it works with the CPU despite Intel not specifying it  :DD

 

As for unraid not liking the GT 730 its more nvidia not liking to be passed through as used adapter for boot and console. That it works without problems just confirms my experience that AMD adapters doesn't have this problem and should be that cards to use if you doesn't have built in graphics in the CPU or motherboard.

 

@ jonp

Maybe it should be added to the unraid 6 manual?

Hmm, if that's the case (Nvidia GPU not allowing passthrough if it's the boot/console GPU), that could explain Jonp's comment in another thread that it will likely work if I have both the Nvidia and AMD cards installed together, especially if the AMD card is used for boot/console.

 

Now that I'm curious, I'll do some testing this week to see if I can replicate it.

I had problem with my motherboard and VT-d.

Gigabyte GA-X58A-UDR3 v.1.0 with beta bios (8AUD3RUS) with VT-d enabled.

Cpu i7-920 and XEON E5620 both work.

 

If I tried to enable GPU passtrough this would pop-up:

internal error: process exited while connecting to monitor: 2015-09-06T16:32:53.970184Z qemu-system-x86_64: -device vfio-pci,host=03:00.0,bus=pcie.0,multifunction=on,x-vga=on: vfio: failed to set iommu for container: Operation not permitted
2015-09-06T16:32:53.970216Z qemu-system-x86_64: -device vfio-pci,host=03:00.0,bus=pcie.0,multifunction=on,x-vga=on: vfio: failed to setup container for group 17
2015-09-06T16:32:53.970225Z qemu-system-x86_64: -device vfio-pci,host=03:00.0,bus=pcie.0,multifunction=on,x-vga=on: vfio: failed to get group 17
2015-09-06T16:32:53.970236Z qemu-system-x86_64: -device vfio-pci,host=03:00.0,bus=pcie.0,multifunction=on,x-vga=on: Device initialization failed
2015-09-06T16:32:53.970247Z qemu-system-x86_64: -device vfio-pci,host=03:00.0,bus=pcie.0,multifunction=on,x-vga=on: Device 'vfio-pci' could not be initialized

 

I then searched the web and added bolded text to syslinux/syslinux.cfg

default /syslinux/menu.c32

menu title Lime Technology

prompt 0

timeout 50

label unRAID OS

  menu default

  kernel /bzimage

  append intel_iommu=on vfio_iommu_type1.allow_unsafe_interrupts=1 initrd=/bzroot

label unRAID OS Safe Mode (no plugins)

  kernel /bzimage

  append initrd=/bzroot unraidsafemode

label Memtest86+

  kernel /memtest

 

And I got it to work. Installed Win8.1 to test it.

 

Very nice tip!  And thank you for the time taken to research it, test it, and write it up.

 

Off-topic, a question/thought to all VM enthusiasts - There a number of tips scattered around through these VM threads (mostly from JonP!), and seems like they should be gathered into one place, easy to find.  I'm not sure of the best form for it, an index, a FAQ, something else...  And I'm not sure of the best location, a stickied thread here, or a wiki page, or something else.  Whether this fits into a FAQ form or not, I do believe a VM FAQ could be helpful, so Jon and others don't have to keep answering the same questions (e.g. "onboard GPU supported?", lost XML edits, etc).

 

I still haven't had time to play with VM's myself, but will be happy to help, such as setting anything up that may be desired, if needed.