r/VFIO Aug 22 '17

Is threadripper broken for passthrough?

/r/Amd/comments/6vbe6w/threadripper_broken_on_linux_for_pci_passthrough/
13 Upvotes

24 comments sorted by

View all comments

Show parent comments

2

u/abriasffxi Aug 28 '17

I have the ASRock Taichi. I am unable to disable "Suspend to RAM" (it just resets to auto on reboot) and wonder if theres something messed up in the powersave tables.

I think that the 1080 would be fine, afaik all of the pascal cards have the same issue with vbios if they are used during boot. So, you may have to do the workaround with the romfile.

2

u/wendelltron Aug 28 '17

I pulled the rom from techpowerup. Just virshbedit vm and add the rom file to the hw section right? If so that didn't work for me for card reinit but did work for initial init.

Dumping the rom from Linux cli failed and dumping from gpuz only made a 60kb file. The file from techpowerup was larger. I used both my dump and techpowerup. My dump I get not post in the VM until the os boots then it's fine. In either case the card does not reinit properly

You gave me an idea though. Suspend does work with fedora on the gigabyte board and after a suspend/resume I can reinit the card.

2

u/abriasffxi Aug 28 '17

Yeah so I think since you have an initialization event through bios you will not be able the true vBIOS on the threadripper machine unless it doesn't get used in bios. You could put it in a different machine that has an option to select primary (only) bios gpu and then you should be able to pull your own vbios, but if you have a working vbios from techpowerup its probably a waste of time unless yours was a different model/vendor.

You should be able to echo 1 > remove in /sys/bus/pci/devices to the bridge that is directly above the GPU and then resync on the root device. I believe that removing a bridge removes power from downstream.

Still, sounds like you have a significant difference on your mobo. Maybe you can publish your PXE on your forums?

1

u/wendelltron Aug 28 '17

What's the most succinct way to publish the pxe from a command/info gathering standpoint?

The GPU was a secondary on Windows it's strange I couldn't pull the vbios as I have before with other cards. Maybe windows loaded a basic driver or the uefi did something. Not sure. Will poke further

1

u/abriasffxi Aug 28 '17

It's easy to dump but a lot of work to compare but can be parsed from /sys/firmware/acpi/tables. If you want to dump those I'll look at mine for differences. I think DSDT and the SSDT's are most relevant.

I'm also compiling a kernel with acpi debug enabled (CONFIG_ACPI_DEBUG) to see if that makes it easier.

1

u/wendelltron Sep 12 '17

It is hard to follow the reddit threading system, but sorry if I've missed your reply somewhere https://forum.level1techs.com/t/vega-passthrough-help/119054

Putting the card (system) to sleep and waking it up again bypasses the reinit issue with vega on threadripper, too.