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icefox99

Member

Registered: 2023-05-24

Posts: 11

SDDM fails to load after GPU passthrough [Resolved]

Hello I am on a 2 gpu system and after doing a gpu passthrough the my sddm refuses to load on boot.
I believe that it has to do with it trying to load on my NVIDIA gpu that is being passed since when I unplug it from my display the issue goes away however I do not know exactly what is causing it.
Here is my Xorg.0 log if its any help: https://pastebin.pl/view/da284972

Last edited by icefox99 (2023-05-25 21:50:30)

seth

Member

From: Won't reply 2 private help req

Registered: 2012-09-03

Posts: 75,317

Re: SDDM fails to load after GPU passthrough [Resolved]

[    32.643] Kernel command line: BOOT_IMAGE=/vmlinuz-linux root=UUID=5c8bc13a-0060-4059-abad-6bbe6f702eb7 rw cryptdevice=UUID=f4f996ab-5071-4b02-b5fb-508213c21b3d:cryptlvm rootfstype=ext4 loglevel=3
iommu=pt amd_iommu=on vfio_pci.ids=10de:10f9,10de:1ada,10de:1adb,10de:1f08 vfio_pci.disable_vga=1

[    32.700] (--) PCI: (6@0:0:0) 1002:73df:1462:3980 rev 193, Mem @ 0xd0000000/268435456, 0xe0000000/2097152, 0xfc200000/1048576, I/O @ 0x0000f000/256, BIOS @ 0x????????/131072
[    32.700] (--) PCI:*(9@0:0:0) 10de:1f08:1462:3752 rev 161, Mem @ 0xfb000000/16777216, 0xb0000000/268435456, 0xc0000000/33554432, I/O @ 0x0000e000/128, BIOS @ 0x????????/524288

Xorg still shows the nvidia GPU as primary device, not sure whether your passthrough actually works.

[    32.790] (EE) Cannot run in framebuffer mode. Please specify busIDs        for all framebuffer devices

1st off all, remove all xf86-video-* packages you installed, notably the -ati one.

Iff the problem remains, add

Section "Device"
    Identifier     "AMD"
    Driver         "modesetting"
    BusID          "PCI:6:0:0"
EndSection

as eg. /etc/X11/xorg.conf.d/amd-device.conf

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How to upload text · How to boot w/o GUI · Disable Windows Fast-Start! · Fix your xinitrc

icefox99

Member

Registered: 2023-05-24

Posts: 11

Re: SDDM fails to load after GPU passthrough [Resolved]

Yeah that seemed to do it after adding

Section "Device"
    Identifier     "AMD"
    Driver         "modesetting"
    BusID          "PCI:6:0:0"
EndSection

seth

Member

From: Won't reply 2 private help req

Registered: 2012-09-03

Posts: 75,317

Re: SDDM fails to load after GPU passthrough [Resolved]

\o/

Please always remember to mark resolved threads by editing your initial posts subject - so others will know that there's no task left, but maybe a solution to find.
Thanks.

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How to upload text · How to boot w/o GUI · Disable Windows Fast-Start! · Fix your xinitrc

torrenator

Member

Registered: 2020-11-08

Posts: 9

Re: SDDM fails to load after GPU passthrough [Resolved]

Amazing work @seth
I got to fix the same issue with a AMD dGPU and iGPU by switching the primary GPU.

Lone_Wolf

Administrator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 14,973

Re: SDDM fails to load after GPU passthrough [Resolved]

Please don't necro-bump

Closing this old thread.

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Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

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