Nvidia borked how ro reconfigure

deano_ferrari · March 26, 2026, 10:58pm

I was speculating if related to this ddcutil regression…

github.com/rockowitz/ddcutil

BUG - ddcutil 2.2.5 causes KDE Plasma freeze due to excessive i2c permission checks

opened 03:20PM - 05 Feb 26 UTC

closed 11:17AM - 27 Jul 26 UTC

tldmt

bug Fixed PowerDevil kde permissions Framework computer 2.2.5 EACCES

## Problem Description After updating from ddcutil 2.2.3 to 2.2.5, KDE Plasma co…mpletely freezes after login. The desktop loads but nothing responds *visually*. ## Environment - **Distribution:** Arch Linux - **Kernel:** 6.17.7-arch1-1 - **ddcutil version (broken):** 2.2.5-1 - **ddcutil version (working):** 2.2.3-1 - **KDE Plasma:** 6.5.5 - **powerdevil:** 6.5.5-1 - **kwin:** 6.5.5-3 - **GPUs:** - NVIDIA GeForce RTX 3050 Mobile (GA107M) - AMD Radeon 680M (Rembrandt) ## Apparent Root Cause The new version (2.2.5) seems to aggressively and repeatedly try to access all i2c devices (/dev/i2c-0 through /dev/i2c-23) without having the necessary permissions, causing powerdevil to loop continuously with permission errors. ## Evidence from journalctl ``` fev 05 11:48:28 nb org_kde_powerdevil[2588]: [ 2701] Device /dev/i2c-23 lacks R/W permissions fev 05 11:48:28 nb org_kde_powerdevil[2588]: [ 2701] (dw_remove_display_by_businfo) No Display_Ref found for i2c bus: 1 fev 05 11:48:28 nb org_kde_powerdevil[2588]: [ 2701] (dw_remove_display_by_businfo) No Display_Ref found for i2c bus: 10 fev 05 11:48:28 nb org_kde_powerdevil[2588]: [ 2701] Device /dev/i2c-1 lacks R/W permissions fev 05 11:48:28 nb org_kde_powerdevil[2588]: [ 2701] Device /dev/i2c-2 lacks R/W permissions [... repeated for all 24 i2c devices, multiple times ...] ``` > This generates continuous DDCA_EVENT_DISPLAY_CONNECTED events that lock up the system. ## Workaround Downgrading to ddcutil 2.2.3-1 **immediately** resolves the issue. [ddcutil_interrogate.txt](https://github.com/user-attachments/files/25099845/ddcutil_interrogate.txt)