Desktop blackscreen susddenly after installing Riot Vangaurd on Windows installation

I updated League of Legends last night to play with some friends and had to install the Vanguard anti-cheat. Now, when I boot NixOS, which is on a separate drive, after logging in at the SDDM screen I boot to a black desktop. Cursor is visible.

The display still works partially: I have discord set to run on startup and the updating popup shows as usual. I was able to get to my terminal using my shortcut, and then run firefox where I am typing this now. But the desktop is black, the taskbar is gone, and the start menu does not appear when pressing Meta/Windows. I can also tell my refresh rate is a lot lower.

The only changes I made were updating League/installing Vanguard and changing a thermal setting in BIOS (back to a default that NixOS booted just fine with previously.

Uninstalling League and Vanguard did not solve the issue.

I tried making a new user to see if that user worked properly like here: NixOS + Wayland + Plasma + Nvidia causes black screen on login with only mouse visible - #2 by JackPala but the new user has the same issue.

I tried plasma5 and things seemed to work, although I think it was using x11, not wayland.

Here is some of the recent history in dmesg, I’m not sure what is going on with llvmpipe here:

[  543.955054] llvmpipe-10[1565]: segfault at 145fc ip 00007fa6e4e0a2fc sp 00007fa6dcbff480 error 4
[  543.955056] llvmpipe-12[1567]: segfault at 14400 ip 00007fa6e4e0a2fc sp 00007fa6d33ff400 error 4
[  543.955058] llvmpipe-14[1569]: segfault at 1b5ec ip 00007fa6e4e0a2fc sp 00007fa6d1fff400 error 4 likely on CPU 4 (core 2, socket 0)
[  543.955062]  likely on CPU 3 (core 1, socket 0)
[  543.955062]  likely on CPU 10 (core 5, socket 0)



[  543.955066] Code: 40 f4 c5 b5 db e4 c5 8d db e4 c5 cd fe e4 c5 4d fe cd c5 45 fe f6 c5 c9 ef f6 c5 5d fe c7 c5 dd fe ed c5 dd 76 e4 c5 c1 ef ff <c4> 82 5d 90 34 0f c4 41 35 76 c9 c5 dd 76 e4 c4 82 5d 90 3c 37 c4
[  543.955067] Code: 40 f4 c5 b5 db e4 c5 8d db e4 c5 cd fe e4 c5 4d fe cd c5 45 fe f6 c5 c9 ef f6 c5 5d fe c7 c5 dd fe ed c5 dd 76 e4 c5 c1 ef ff <c4> 82 5d 90 34 0f c4 41 35 76 c9 c5 dd 76 e4 c4 82 5d 90 3c 37 c4
[  543.955067] Code: 40 f4 c5 b5 db e4 c5 8d db e4 c5 cd fe e4 c5 4d fe cd c5 45 fe f6 c5 c9 ef f6 c5 5d fe c7 c5 dd fe ed c5 dd 76 e4 c5 c1 ef ff <c4> 82 5d 90 34 0f c4 41 35 76 c9 c5 dd 76 e4 c4 82 5d 90 3c 37 c4
[  543.955069] llvmpipe-3[1557]: segfault at fc ip 00007fa6e4e0a2fc sp 00007fa6e57ff400 error 4
[  543.955070] llvmpipe-11[1566]: segfault at 0 ip 00007fa6e4e0a2fc sp 00007fa6d3dff380 error 4
[  543.955071] llvmpipe-7[1561]: segfault at 4fc ip 00007fa6e4e0a2fc sp 00007fa6de9ff400 error 4
[  543.955071] llvmpipe-0[1554]: segfault at 5fc ip 00007fa6e4e0a2fc sp 00007fa6eddff380 error 4
[  543.955072]  likely on CPU 2 (core 1, socket 0)
[  543.955073] llvmpipe-9[1563]: segfault at 2fc ip 00007fa6e4e0a2fc sp 00007fa6dd5ff400 error 4
[  543.955074]  likely on CPU 11 (core 5, socket 0)
[  543.955074] Code: 40 f4 c5 b5 db e4 c5 8d db e4 c5 cd fe e4 c5 4d fe cd c5 45 fe f6 c5 c9 ef f6 c5 5d fe c7 c5 dd fe ed c5 dd 76 e4 c5 c1 ef ff <c4> 82 5d 90 34 0f c4 41 35 76 c9 c5 dd 76 e4 c4 82 5d 90 3c 37 c4
[  543.955074]  likely on CPU 14 (core 7, socket 0)

[  543.955077]  likely on CPU 13 (core 6, socket 0)
[  543.955076]  likely on CPU 12 (core 6, socket 0)

[  543.955076] llvmpipe-4[1558]: segfault at 6fc ip 00007fa6e4e0a2fc sp 00007fa6e4dff380 error 4
[  543.955077] Code: 40 f4 c5 b5 db e4 c5 8d db e4 c5 cd fe e4 c5 4d fe cd c5 45 fe f6 c5 c9 ef f6 c5 5d fe c7 c5 dd fe ed c5 dd 76 e4 c5 c1 ef ff <c4> 82 5d 90 34 0f c4 41 35 76 c9 c5 dd 76 e4 c4 82 5d 90 3c 37 c4
[  543.955077] llvmpipe-13[1568]: segfault at 7fc ip 00007fa6e4e0a2fc sp 00007fa6d29ff380 error 4

[  543.955077] Code: 40 f4 c5 b5 db e4 c5 8d db e4 c5 cd fe e4 c5 4d fe cd c5 45 fe f6 c5 c9 ef f6 c5 5d fe c7 c5 dd fe ed c5 dd 76 e4 c5 c1 ef ff <c4> 82 5d 90 34 0f c4 41 35 76 c9 c5 dd 76 e4 c4 82 5d 90 3c 37 c4

[  543.955079] Code: 40 f4 c5 b5 db e4 c5 8d db e4 c5 cd fe e4 c5 4d fe cd c5 45 fe f6 c5 c9 ef f6 c5 5d fe c7 c5 dd fe ed c5 dd 76 e4 c5 c1 ef ff <c4> 82 5d 90 34 0f c4 41 35 76 c9 c5 dd 76 e4 c4 82 5d 90 3c 37 c4
[  543.955081] Code: 40 f4 c5 b5 db e4 c5 8d db e4 c5 cd fe e4 c5 4d fe cd c5 45 fe f6 c5 c9 ef f6 c5 5d fe c7 c5 dd fe ed c5 dd 76 e4 c5 c1 ef ff <c4> 82 5d 90 34 0f c4 41 35 76 c9 c5 dd 76 e4 c4 82 5d 90 3c 37 c4
[  543.955081]  likely on CPU 6 (core 3, socket 0)
[  543.955081]  likely on CPU 1 (core 0, socket 0)

[  543.955083] Code: 40 f4 c5 b5 db e4 c5 8d db e4 c5 cd fe e4 c5 4d fe cd c5 45 fe f6 c5 c9 ef f6 c5 5d fe c7 c5 dd fe ed c5 dd 76 e4 c5 c1 ef ff <c4> 82 5d 90 34 0f c4 41 35 76 c9 c5 dd 76 e4 c4 82 5d 90 3c 37 c4
[  543.955085] Code: 40 f4 c5 b5 db e4 c5 8d db e4 c5 cd fe e4 c5 4d fe cd c5 45 fe f6 c5 c9 ef f6 c5 5d fe c7 c5 dd fe ed c5 dd 76 e4 c5 c1 ef ff <c4> 82 5d 90 34 0f c4 41 35 76 c9 c5 dd 76 e4 c4 82 5d 90 3c 37 c4
[  549.542823] nvidia-modeset: WARNING: GPU:0: Chimei innolux corp. (DP-4): G-SYNC Compatible: EDID min refresh rate invalid, disabling G-SYNC Compatible.
[  549.613127] nvidia-modeset: WARNING: GPU:0: Chimei innolux corp. (DP-4): G-SYNC Compatible: EDID min refresh rate invalid, disabling G-SYNC Compatible.
[  550.443261] nvidia-modeset: WARNING: GPU:0: Chimei innolux corp. (DP-4): G-SYNC Compatible: EDID min refresh rate invalid, disabling G-SYNC Compatible.
[  550.906427] nvidia-modeset: WARNING: GPU:0: Chimei innolux corp. (DP-4): G-SYNC Compatible: EDID min refresh rate invalid, disabling G-SYNC Compatible.
[  550.911069] nvidia-modeset: WARNING: GPU:0: Chimei innolux corp. (DP-4): G-SYNC Compatible: EDID min refresh rate invalid, disabling G-SYNC Compatible.
[  551.119180] [drm] [nvidia-drm] [GPU ID 0x00000100] Framebuffer memory not appropriate for scanout
[  551.119946] [drm] [nvidia-drm] [GPU ID 0x00000100] Framebuffer memory not appropriate for scanout
[  551.260862] nvidia-modeset: WARNING: GPU:0: Chimei innolux corp. (DP-4): G-SYNC Compatible: EDID min refresh rate invalid, disabling G-SYNC Compatible.
[  552.042902] nvidia-modeset: WARNING: GPU:0: Chimei innolux corp. (DP-4): G-SYNC Compatible: EDID min refresh rate invalid, disabling G-SYNC Compatible.
[  711.128613] simple-framebuffer simple-framebuffer.0: swiotlb buffer is full (sz: 1716224 bytes), total 32768 (slots), used 1540 (slots)

Adding boot.kernelParams = [ "nvidia-drm.modeset=1" "nvidia-drm.fbdev=1" ]; to my configuration.nix file solved the issue. I don’t know why this became necessary suddenly.