I have a freshly installed Arch KDE plasma system running under Proxmox with a passed-through raedeon rx 7900 xtx GPU, the VM is using llvmpipe instead of my GPU.
$ glxinfo | grep "OpenGL renderer"
OpenGL renderer string: llvmpipe (LLVM 18.1.8, 256 bits)
It looks like Xorg is detecting and using the correct gpu
[ 9.803] (II) xfree86: Adding drm device (/dev/dri/card0)
[ 9.803] (II) Platform probe for /sys/devices/pci0000:00/0000:00:02.0/drm/card0
[ 9.803] (II) xfree86: Adding drm device (/dev/dri/card1)
[ 9.803] (II) Platform probe for /sys/devices/pci0000:00/0000:00:10.0/drm/card1
[ 9.839] (**) OutputClass "AMD" setting /dev/dri/card1 as PrimaryGPU
[ 9.842] (--) PCI: (0@0:2:0) 1234:1111:1af4:1100 rev 2, Mem @ 0xf0000000/16777216, 0xfeb74000/4096, BIOS @ 0x????????/131072
[ 9.842] (--) PCI:*(0@0:16:0) 1002:744c:1849:5304 rev 200, Mem @ 0x640000000/268435456, 0x650000000/2097152, 0xfea00000/1048576, I/O @ 0x0000f000/256, BIOS @ 0x????????/131072
[ 9.842] (WW) Open ACPI failed (/var/run/acpid.socket) (No such file or directory)
[...]
[ 10.077] (II) AMDGPU: Driver for AMD Radeon:
All GPUs supported by the amdgpu kernel driver
[ 10.079] (II) AMDGPU(0): Creating default Display subsection in Screen section
"Default Screen Section" for depth/fbbpp 24/32
[ 10.079] (==) AMDGPU(0): Depth 24, (--) framebuffer bpp 32
[ 10.079] (II) AMDGPU(0): Pixel depth = 24 bits stored in 4 bytes (32 bpp pixmaps)
[ 10.079] (==) AMDGPU(0): Default visual is TrueColor
[ 10.079] (II) Applying OutputClass "AMDgpu" options to /dev/dri/card1
[ 10.079] (II) Applying OutputClass "AMD" options to /dev/dri/card1
I had to configure xorg to prefer my graphics card(following [SOLVED] OpenGL renderer string: llvmpipe - AMD Radeon RX 6600 / Kernel & Hardware / Arch Linux Forums):
$ ls /etc/X11/xorg.conf.d/
00-keyboard.conf 20-amdgpu.conf
$ cat /etc/X11/xorg.conf.d/20-amdgpu.conf
Section "OutputClass"
Identifier "AMD"
MatchDriver "amdgpu"
Driver "amdgpu"
Option "PrimaryGPU" "yes"
EndSection
Section "Device"
Identifier "AMD"
Driver "amdgpu"
EndSection
I installed xrandr and it shows no providers
$ sudo xrandr --listproviders
Providers: number : 0
Log files:
dmesg.txt (57.2 KB)
lspci.txt (7.5 KB)
Xorg.0.txt (26.5 KB)