[vfio-users] VM doesn't boot if I use GPU passthrough

[Alexander Petrenz]

Hi Ruben,

I guess your 750ti also has some audio device. You should pass through this
too. It should be something like 01:00.1. There are many command line
examples you can find about that.
Also I´m not quite sure, if you should remove the x-vga=on.

Regards
Alex

On Sun, Jan 17, 2016 at 11:12 PM, Ruben Felgenhauer <
4felgenh at informatik.uni-hamburg.de> wrote:

> Hi,
>
> I am trying to pass my nVidia GTX 750ti to my QEMU guest.
>
> Problem is: After the QEMU monitor pops up, nothing happens. The GPU's
> output is dead, and the vm won't be accessible via SSH anymore, so it's
> very likely that the VM isn't booting up at all. Also, there are no error
> messages from QEMU on the console whatsoever which makes debugging it
> especially hard.
>
> This is how I start the vm with normal vga emulation:
> qemu-system-x86_64 -hda vm.ovl -boot c -enable-kvm -m 1024 -cpu
> host,kvm=off -smp cores=4,threads=2 -redir tcp:5022::22
> Everything runs fine in this case. To do the passthrough, I add this:
> -device vfio-pci,host=01:00.0,multifunction=on,x-vga=on -vga none
> This brings said problems with it. I also tried out multiple different
> combinations of -device's arguments or even adding a romfile for the GPU,
> but none of these steps changed anything at all.
>
> Obviously, I am using a BIOS installation and I'm well-aware with this
> bug: https://bugzilla.kernel.org/show_bug.cgi?id=107561, but neither
> using less RAM (as you can see I am using 1GB now) nor switching to an
> older Kernel changed anything about the problem. I have tried Kernel 4.1.0
> and 4.3.0.
>
> Host is Debian testing with QEMU 2.5.0.
> I tried both Debian and Windows 7 as a guest, but both are showing exactly
> the same behaviour.
> Mainboard is an ASUS Z87-PLUS. The 750ti is produced by ASUS aswell.
>
> Any idea how I could get passthrough running?
>
> _______________________________________________
> vfio-users mailing list
> vfio-users at redhat.com
> https://www.redhat.com/mailman/listinfo/vfio-users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/vfio-users/attachments/20160118/cc3b012d/attachment.htm>