KVM - Looking for a guide for PCIe Passthrough on non-uefi setting

So I’ve been playing with setting up the PCIe passthrough - it seems I’ve isolated the device successfuly and have required modules loaded.
But the problem is the extra graphic card I have at my disposal does not have uefi support. And sadly all the guides I’ve found explain howto set it up for UEFI, with a note that for BIOS option you need to do it differently, but sadly not how.
Can anyone guide me to a tutorial that would explain how to do it? I’m so far into this project I don’t want to leave it. Heck, one of he cards even boots in uefi mode (even though it does not support it), but it is really unreliable in this scenario - locks up during vm reboots. And sadly it does not seem I’ll get another card (with uefi enabled bios) in the next couple of days.

A couple of random google hits:


Those don’t answer my question - my guess is you misunderstood it (my apologies for not being clearer - english is not my native language).
Those tutorials explain howto set up kvm and passthrough in general. I’m past this stage.
What I’m looking for is a guide that would explain howto set it up when your gpu does not support uefi. In other words when you choose BIOS in the vm settings, not UEFI.
I have the gpu isolated and passed to vm - but I don’t know howto set it up so it would work with non uefi boot capable gpus.

For anyone to understand your situation exactly, you have to provide a detailed description.
Recommend you post the guide or reference you used to set up your HostOS and Guest(or attempt to set up the Guest).
If that is not available, then you may need to post a detailed step by step description of what you did.

At the moment I’m unclear about your MBR vs UEFI problem, there may be something new or something unique to your setup but ordinarily any kind of hardware pass-through has nothing to do with how your disks are initiated.

Also, are you trying to do some kind of GPU computing?


ahhhh… I think I know where the confusion originates from . I was talking about setting virtual (not my physical) machine setting to regular BIOS:

  • as my secondary gpu is not uefi capable. I have 2 old cards (Radeon and Nvidia Quadro 600) apart from my GTX 1050 , but neither of those work (both are non-uefi). Quadro almost does - system boots and I get a video from the passed-through card , but as it is non-uefi I get some issues (for example - freezes on reboot).
    There are plenty of guides that show howto do when you have a newer card - for exampl this one (which was a start for me):

  • but I still yet to find one that would explain what you need to do to make “BIOS” setting to work with passthrough (I found 2 that mention - additional steps are needed… and that’s all).

So I have IOMMU groups sorted out, I know the gpu addresses, I have “locked” the card from my linux host system with vfio (pci-stub also does the trick - tried both options) - this part works.

I am having the same issue and just wanted to know if you ever found a solution…I saw where you could download a bios file for many of the cards and I grabbed the one for my card but I cannot find a clear instruction as to how to get the vm to enable it. Mine is a xfx 6870 which is known to work. I too have it isolated grub changed and a new intrid file created. I think that the last step is to use that file which makes it EFI capable? …but I cannot figure out how to do it.

GPU pass through has/had been on the bleeding edge for many years, but about a year ago KVM and Xen finally started becoming more stablized.

The following is what I posted a year ago which was a good snapshot of the state of art at that time. There might have been further developments since, but the following article is a good place to start. The wiki references in particular are “living” articles which are continuously updated and should be as up to date even today as you can get.