[SOLVED] PCI Passthrough Causes Host to Reboot

jmjohnson · 2024-06-20 14:07:35

I have a Kill A Watt and plugged the computer into that. Powering on the host and guest only pulls about 110W so pretty sure it's not a power issue. The system also boots and runs games in Windows just fine so I'm not convinced it's an issue with bad hardware.

cryptearth · 2024-06-20 14:37:23

well - just the draw from the wall doesn't tell anything about whats happen inside the system
it could very well that a bad component causes a high resitance and thereby high temp which might trigger some safety
I doubt it's the software either as by my tests - as long your configs not too messed up
it's just a logical conclusion that the when its not the software running fine on everybody elses system only the hardware is left - which is either just incompatible - or broken

seth · 2024-06-20 14:55:33

1. you've not clarified whether it's actually the host or the (virtual) guest that reboots, https://bbs.archlinux.org/viewtopic.php … 6#p2177356
2. the problem went away when swapping the GPU?
3. ryzen is on the record for this kind of problem, https://wiki.archlinux.org/title/Ryzen#Random_reboots - this has nothing to do with your PSU, you need stable voltage on the core and any PCIe burst could dip this
4. 3rd link below. Mandatory.
Disable it (it's NOT the BIOS setting!) and reboot windows and linux twice for voodo reasons.
(Though I don't expect it to be the cause of the random reboots in this particular instance)

jmjohnson · 2024-06-20 16:41:59

Seth, it was the host that was rebooting. It looks like I finally figured it out though. I dumped the video card bios (via GPU-Z in Windows) and loaded it by editing the xml. Here's a snippet of my xml file with the rom loaded:

<hostdev mode='subsystem' type='pci' managed='yes'>
  <driver name='vfio'/>
  <source>
    <address domain='0x0000' bus='0x03' slot='0x00' function='0x0'/>
  </source>
  <alias name='hostdev2'/>
  <rom file='/var/lib/libvirt/qemu/radeon7800xt.rom'/>
  <address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/>
</hostdev>

I was able to boot the Arch guest into Gnome and load a few games in Steam. I guess it's on to finishing the setup and optimizing now!

Thank you everyone so much for your help with this, I'll mark the topic resolved.

cryptearth · 2024-06-20 18:14:31

although I know about this "dumping the vbios" I doubt that's the cause, no matter it seems one possible working solution

seth · 2024-06-20 19:54:14

Is windows fast-start disabled?

Beuman · 2025-01-21 13:56:51

jmjohnson wrote:

Seth, it was the host that was rebooting. It looks like I finally figured it out though. I dumped the video card bios (via GPU-Z in Windows) and loaded it by editing the xml. Here's a snippet of my xml file with the rom loaded:
<hostdev mode='subsystem' type='pci' managed='yes'>
  <driver name='vfio'/>
  <source>
    <address domain='0x0000' bus='0x03' slot='0x00' function='0x0'/>
  </source>
  <alias name='hostdev2'/>
  <rom file='/var/lib/libvirt/qemu/radeon7800xt.rom'/>
  <address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/>
</hostdev>
I was able to boot the Arch guest into Gnome and load a few games in Steam. I guess it's on to finishing the setup and optimizing now!
Thank you everyone so much for your help with this, I'll mark the topic resolved.

Hello jmJohnson. I have the same issue with my 7800XT rebooting the host.
I use Proxmox hypervisor and try to GPU Passthrough to an Archlinux VM. Can you please explain me how you loaded the new rom and how did you know what edit were necessary ? Thanks in advance, I have been struggling with that graphic card

jmjohnson · 2025-01-21 17:42:02

Hi Beuman,

To get the video card bios from my card I used the GPU-Z utility from techpowerup.com. Unfortunately this utility only works in Windows, so you may need a different utility if you don't have access to Windows. It does look like they have a number of video BIOSes for the 7899XT now in their repository so you might be able to use one of them if you can't extract yours: https://www.techpowerup.com/vgabios/

As far as editing the file I think it was just the <rom file> entry I needed to add/edit but I don't recall. Unfortunately I ended up scrapping the whole thing and went with dual booting my system in the end so I really don't remember what I changed now. Hopefully that gets you going in the right direction though.

Beuman · 2025-01-23 17:07:15

Thanks for your answer. If you went with the Dual Boot solution I imagine you had stability issues.... which is a problem for a server. I imagine AMD Instinct line does a better job but I don't think their could be some good one for gaming

Arch Linux

#26 2024-06-20 14:07:35

Re: [SOLVED] PCI Passthrough Causes Host to Reboot

#27 2024-06-20 14:37:23

Re: [SOLVED] PCI Passthrough Causes Host to Reboot

#28 2024-06-20 14:55:33

Re: [SOLVED] PCI Passthrough Causes Host to Reboot

#29 2024-06-20 16:41:59

Re: [SOLVED] PCI Passthrough Causes Host to Reboot

#30 2024-06-20 18:14:31

Re: [SOLVED] PCI Passthrough Causes Host to Reboot

#31 2024-06-20 19:54:14

Re: [SOLVED] PCI Passthrough Causes Host to Reboot

#32 2025-01-21 13:56:51

Re: [SOLVED] PCI Passthrough Causes Host to Reboot

#33 2025-01-21 17:42:02

Re: [SOLVED] PCI Passthrough Causes Host to Reboot

#34 2025-01-23 17:07:15

Re: [SOLVED] PCI Passthrough Causes Host to Reboot

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