Setting this environment variable VK_ICD_FILENAMES breaks gamescope

[Tweakkinn]

I finally got gamescope working after a lot of trail and error this env variable was the culprit

VK_ICD_FILENAMES=/usr/share/vulkan/icd.d/radeon_icd.json

Initially I thought it broke gamescope because radeon_icd.json isn't the correct file name it is radeon_icd.x86_64.json for my system

❯ ls /usr/share/vulkan/icd.d/
.rw-r--r-- 140 root 24 Mar 08:29  nvidia_icd.json
.rw-r--r-- 179 root  6 Apr 03:36  radeon_icd.i686.json
.rw-r--r-- 177 root  6 Apr 03:29  radeon_icd.x86_64.json

but after fixing it gamescope would still fail to launch

gamescope log

>WAYLAND_CLIENT=debug gpu-prime gamescope -- vkcube --wsi xcb
[gamescope] [Info]  console: gamescope version 3.16.20+ (gcc 15.2.1)
No CAP_SYS_NICE, falling back to regular-priority compute and threads.
Performance will be affected.
[gamescope] [Info]  scriptmgr: Loading scripts from: '/usr/share/gamescope/scripts'
[gamescope] [Info]  scriptmgr: Loading scripts from: '/usr/share/gamescope/scripts/00-gamescope'
[gamescope] [Info]  scriptmgr: Loading scripts from: '/usr/share/gamescope/scripts/00-gamescope/common'
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/common/inspect.lua' (id: 0)
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/common/modegen.lua' (id: 1)
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/common/util.lua' (id: 2)
[gamescope] [Info]  scriptmgr: Loading scripts from: '/usr/share/gamescope/scripts/00-gamescope/displays'
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/displays/asus.rogally.lcd.lua' (id: 3)
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/displays/deckhd.steamdeck.deckhd-lcd.lua' (id: 4)
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/displays/gpd.win4.lcd.lua' (id: 5)
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/displays/lenovo.legiongo.lcd.lua' (id: 6)
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/displays/lenovo.legiongos.lcd.lua' (id: 7)
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/displays/onexplayer.f1.oled.lua' (id: 8)
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/displays/valve.steamdeck.lcd.lua' (id: 9)
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/displays/valve.steamdeck.oled.lua' (id: 10)
[gamescope] [Info]  scriptmgr: Running script file '/usr/share/gamescope/scripts/00-gamescope/displays/zotac.zone.oled.lua' (id: 11)
[gamescope] [Info]  scriptmgr: Loading scripts from: '/etc/gamescope/scripts'
[gamescope] [Warn]  scriptmgr: Directory '/etc/gamescope/scripts' does not exist
[gamescope] [Info]  scriptmgr: Loading scripts from: '/home/tweak/.config/gamescope/scripts'
[gamescope] [Warn]  scriptmgr: Directory '/home/tweak/.config/gamescope/scripts' does not exist
[gamescope] [Info]  vulkan: selecting physical device 'NVIDIA GeForce RTX 5070 Ti': queue family 2 (general queue family 0)
[gamescope] [Info]  vulkan: physical device supports DRM format modifiers
[gamescope] [Info]  wlserver: [backend/headless/backend.c:67] Creating headless backend
[gamescope] [Info]  xdg_backend: Seat name: seat0
[gamescope] [Info]  xdg_backend: Initted Wayland backend
[gamescope] [Error] vulkan: vkGetPhysicalDeviceFormatProperties2 returned zero modifiers for DRM format 0x38344241 (VkResult: 0)
[gamescope] [Error] vulkan: vkGetPhysicalDeviceFormatProperties2 returned zero modifiers for DRM format 0x38344258 (VkResult: 0)
[gamescope] [Info]  vulkan: supported DRM formats for sampling usage:
[gamescope] [Info]  vulkan:   AR24 (0x34325241)
[gamescope] [Info]  vulkan:   XR24 (0x34325258)
[gamescope] [Info]  vulkan:   AB24 (0x34324241)
[gamescope] [Info]  vulkan:   XB24 (0x34324258)
[gamescope] [Info]  vulkan:   RG16 (0x36314752)
[gamescope] [Info]  vulkan:   NV12 (0x3231564E)
[gamescope] [Info]  vulkan:   AB4H (0x48344241)
[gamescope] [Info]  vulkan:   XB4H (0x48344258)
[gamescope] [Info]  vulkan:   AB30 (0x30334241)
[gamescope] [Info]  vulkan:   XB30 (0x30334258)
[gamescope] [Info]  vulkan:   AR30 (0x30335241)
[gamescope] [Info]  vulkan:   XR30 (0x30335258)
[gamescope] [Info]  wlserver: Using explicit sync when available
[gamescope] [Info]  wlserver: [wayland] unable to lock lockfile /run/user/1000/gamescope-0.lock, maybe another compositor is running
[gamescope] [Info]  wlserver: Running compositor on wayland display 'gamescope-1'
[gamescope] [Info]  wlserver: [backend/headless/backend.c:17] Starting headless backend
[gamescope] [Info]  wlserver: Successfully initialized libei for input emulation!
[gamescope] [Info]  wlserver: [xwayland/server.c:107] Starting Xwayland on :2
The XKEYBOARD keymap compiler (xkbcomp) reports:
Warning:          Multiple symbols for level 1/group 1 on key <FK23>
                  Using F23, ignoring XF86TouchpadOff
Warning:          Symbol map for key <FK23> redefined
                  Using last definition for conflicting fields
Warning:          Symbol map for key <FK24> redefined
                   Using last definition for conflicting fields
Errors from xkbcomp are not fatal to the X server
[gamescope] [Info]  pipewire: stream state changed: connecting
[gamescope] [Info]  pipewire: stream state changed: paused
[gamescope] [Info]  pipewire: stream available on node ID: 80
(EE) failed to read Wayland events: Broken pipe
/usr/bin/gpu-prime: line 20: 15763 Aborted                    (core dumped) __NV_PRIME_RENDER_OFFLOAD=1 __VK_LAYER_NV_optimus=NVIDIA_only __GLX_VENDOR_LIBRARY_NAME=nvidia LIBVA_DRIVER_NAME=nvidia __EGL_VENDOR_LIBRARY_FILENAMES=/usr/share/glvnd/egl_vendor.d/10_nvidia.json VK_ICD_FILENAMES=/usr/share/vulkan/icd.d/nvidia_icd.json "$@"`

I removed that variable from being set and used prime-run instead of gpu-prime to launch steam now it works flawlessly! I got gamescope running with mangohud and HDR working correctly.

My current launch options

gamescope --hdr-enabled --force-grab-cursor -W 2560 -H 1440 -f -r 480 --mangoapp -- env PROTON_VKREFLEX=1 PROTON_DLSS_UPGRADE=1 PROTON_USE_NTSYNC=1 PROTON_VKD3D_HEAP=1 DXVK_NVAPI_DRS_NGX_DLSS_FG_OVERRIDE_RENDER_PRESET_SELECTION=render_preset_b prime-run game-performance %command% --useallavailablecores

to get gamescope with mangohud and HDR you only need

gamescope --hdr-enabled -W 2560 -H 1440 -f -r 480 --mangoapp -- env prime-run %command%

I have found that I need to manually set this env variable for each app I don't want interfering with launching my VM or it will fail to unload the NVIDIA driver. You can also just close the app.

[SocketByte]

Lack of this environment variable (as you noticed) causes issue with NVIDIA being claimed by Chromium-based apps. (Brave/Chrome or anything Electron).

If I understand correctly, gamescope worked for you after NOT setting VK_ICD_FILESNAMES to NVIDIA ICD right? It would seem so because gpu-prime sets this variable for that particular app, prime-run does not.

[mikigal]

Please share what's value of VK_ICD_FILENAMES in your system when gamescope works
Best way to fix this problem should be using your value of VK_ICD_FILENAMES for games, and radeon_icd/radeon_icd.x86_64.json for rest of system as apps will block NVIDIA GPU without it

[Tweakkinn]

It seems VK_ICD_FILENAMES has no value if not set. Setting VK_LOADER_DEBUG=all I was able to see what was being loaded. If no value is set then both drivers will be used.

VK_ICD_FILENAMES=⁄usr⁄share⁄vulkan⁄icd.d⁄radeon_icd.x86_64.json.txt

VK_ICD_FILENAMES=⁄usr⁄share⁄vulkan⁄icd.d⁄nvidia_icd.json.txt

VK_ICD_FILENAMES_UNSET.txt

Setting VK_ICD_FILENAMES=⁄usr⁄share⁄vulkan⁄icd.d⁄radeon_icd.x86_64.json globally and then changing VK_ICD_FILENAMES to VK_ICD_FILENAMES=⁄usr⁄share⁄vulkan⁄icd.d⁄radeon_icd.x86_64.json:⁄usr⁄share⁄vulkan⁄icd.d⁄nvidia_icd.json within gpu-prime works without other apps using the NVIDIA driver

❯ cat /etc/environment.d/envvars.conf
# /etc/environment.d/envvars.conf
# Use AMD as the default GPU

__EGL_VENDOR_LIBRARY_FILENAMES=/usr/share/glvnd/egl_vendor.d/50_mesa.json
VK_ICD_FILENAMES=/usr/share/vulkan/icd.d/radeon_icd.x86_64.json
LIBVA_DRIVER_NAME=radeonsi
__GLX_VENDOR_LIBRARY_NAME=mesa

~
❯ cat /usr/bin/gpu-prime
#!/bin/bash

# GPU PCIe address
GPU="01:00.0"

driver=$(lspci -nnk -s "$GPU" | awk -F': ' '/Kernel driver in use/ {print $2}')

[[ -z "${driver:-}" ]] && fail "Could not find driver in use for $GPU"

if [[ "$driver" != "nvidia" ]]; then
    if [[ -n "${SUDO_USER:-}" ]]; then
        UID_USER=$(id -u "$SUDO_USER")
        sudo -u "#$UID_USER" DBUS_SESSION_BUS_ADDRESS="unix:path=/run/user/$UID_USER/bus" notify-send -i dialog-error -t 3000 "GPU PRIME" "NVIDIA GPU is in passthrough mode, cannot run application"
    else
        notify-send -i dialog-error -t 3000 "GPU PRIME" "NVIDIA GPU is in passthrough mode, cannot run application"
    fi
    exit 1
fi

__NV_PRIME_RENDER_OFFLOAD=1 __VK_LAYER_NV_optimus=NVIDIA_only __GLX_VENDOR_LIBRARY_NAME=nvidia LIBVA_DRIVER_NAME=nvidia __EGL_VENDOR_LIBRARY_FILENAMES=/usr/share/glvnd/egl_vendor.d/10_nvidia.json VK_ICD_FILENAMES=/usr/share/vulkan/icd.d/radeon_icd.x86_64.json:/usr/share/vulkan/icd.d/nvidia_icd.json "$@"

VK_ICD_FILENAMES=⁄usr⁄share⁄vulkan⁄icd.d⁄radeon_icd.x86_64.json:⁄usr⁄share⁄vulkan⁄icd.d⁄nvidia_icd.json.txt