seg faulting in Kubuntu 25.04 on a Razer Blade 15 (2020) with 4K OLED display.

[greylander]

per title line: seg faulting in Kubuntu 25.04 (KDE/Plasma) on a Razer Blade 15 (2020) with 4K OLED display.

Not sure what other info will be helpful, but happy to provide logs, etc, if requested. The seg fault is immediate.

This is while using Plasma/Wayland. Just occurred to me to mention that. Will see what happens with X11.

[Nikl174]

First, build the program again like this:

mkdir build && cd build
cmake -D CMAKE_BUILD_TYPE=Debug ..  # enables debugging artifacts needed for the stack trace
make

Then, can you send the stack trace with gdb like this:

$ gdb -q colord-brightness
(gdb) run
Starting program: colord-brightness
Program received signal SIGSEGV, Segmentation fault.
0x00000000004004fd in fail() ()
(gdb) backtrace
#0  0x00000000004004fd in fail() ()
#1  0x0000000000400513 in main ()

And I need the last part below backtrace.

Thanks for the feedback :D

P.S.: Did you install it with make install?

[greylander]

Will try to do that soon. But here is additional info found in further troubleshooting that may be enough for you to know what's going on: Apparently Razer Blade 15(2020) is not returning good EDID data (see below). Thus colormgr get-devices finds no devices on Plasma(Wayland). For what it is worth, colormgr get-devices does find the display when using Plasma(X11). I could get icc-brightness to work on X11. But not color-brightness.

…

---- $ sudo get-edid | parse-edid This is read-edid version 3.0.2. Prepare for some fun. Attempting to use i2c interface No EDID on bus 0 No EDID on bus 1 Problem requesting slave address: Device or resource busy No EDID on bus 3 No EDID on bus 4 No EDID on bus 5 No EDID on bus 6 No EDID on bus 8 No EDID on bus 9 No EDID on bus 10 No EDID on bus 11 No EDID on bus 12 No EDID on bus 13 1 potential busses found: 7 256-byte EDID successfully retrieved from i2c bus 7 Looks like i2c was successful. Have a good day. Checksum Correct Section "Monitor" Identifier "" ModelName "" VendorName "SDC" # Monitor Manufactured week 8 of 2019 # EDID version 1.4 # Digital Display DisplaySize 340 190 Gamma 2.20 Option "DPMS" "false" #Extension block found. Parsing... extb[4]: 0xe3 (0xe0) Hmm, you have data blocks, but not video ones... weird Something strange happened. Please contact the author, Matthew Kern at ***@***.***>

On Sun, May 18, 2025 at 10:31 AM Nikl174 ***@***.***> wrote: *Nikl174* left a comment (Nikl174/colord-brightness#10) <#10 (comment)> First, build the program again like this: mkdir build && cd build cmake -D CMAKE_BUILD_TYPE=Debug .. # enables debugging artifacts needed for the stack trace make Then, can you send the stack trace with gdb <https://packages.ubuntu.com/plucky/gdb> like this: $ gdb -q colord-brightness (gdb) run Starting program: colord-brightness Program received signal SIGSEGV, Segmentation fault. 0x00000000004004fd in fail() () (gdb) backtrace#0 0x00000000004004fd in fail() ()#1 0x0000000000400513 in main () And I need the last part below backtrace. Thanks for the feedback :D — Reply to this email directly, view it on GitHub <#10 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABRTFTDD2HK23WRRWHLUG5L27CKVHAVCNFSM6AAAAAB5G5CB2WVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQOBZGAZDGNZVG4> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[Nikl174]

Ah ok, could be the issue, because I only use the first automatically found display devices.
Going to implement a better scanning for the displays and also add a configuration option to choose the device ( also return a warning, if no device found and no segfault).

But if you find time, do the steps above to clarify in which part of the code the SEGFAULT happened.

[greylander]

I just did but forgot I'm on X11 at the moment. And the seg fault does not happen with Plasma(X11). However, for what it is worth, color-brightness does not fix what I'd hoped (though perhaps I misunderstood its purpose). My underlying issue is when I reduce brightness down from 100% the black and near-black colors actually brighten and become washed out. In a dark theme, this actually makes the overall screen much brighter "down" to a peak at about 80%, then it actually becomes dimmer as I proceed down from 80% to 0% while the colors remain washed out. My understanding was that color-brightness would fix this problem by in effect catching brightness adjustment events and reducing brightness by changing the color profile taking advantage of the OLED HDR gamut, keeping true blacks true, while technically leaving the brightness setting pinned at 100%. In Plasma(X11), instead of seg fault, this happens(see below), with the "not updated" message occurring just twice as I adjust brightness. Seems like these occur when I change the brightness too quickly, so probably not related to the failure to fix the color/brightness issue above. Also for what it is worth icc-brightness also fails for me in Wayland, but I've gotten it to work in X11. $ ./colord-brightness 2025-05-18 13:46:17,750 WARNING Icc Profile not updated! 2025-05-18 13:46:17,943 WARNING Icc Profile not updated! $ sudo ./colord-brightness 2025-05-18 13:54:17,523 WARNING Icc Profile not updated! 2025-05-18 13:54:20,795 WARNING Icc Profile not updated! 2025-05-18 13:54:23,972 WARNING Icc Profile not updated! 2025-05-18 13:54:25,648 WARNING Icc Profile not updated! 2025-05-18 13:54:33,722 WARNING Icc Profile not updated! 2025-05-18 13:54:38,755 WARNING Icc Profile not updated! 2025-05-18 13:55:03,757 WARNING Icc Profile not updated!

…

On Sun, May 18, 2025 at 1:06 PM Nikl174 ***@***.***> wrote: *Nikl174* left a comment (Nikl174/colord-brightness#10) <#10 (comment)> Ah ok, could be the issue, because I only use the first automatically found display devices. Going to implement a better scanning for the displays and also add a configuration option to choose the device ( also return a warning, if no device found and no segfault). But if you find time, do the steps above to clarify in which part of the code the SEGFAULT happened. — Reply to this email directly, view it on GitHub <#10 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABRTFTHYBDETPHVX727NHMD27C4ZVAVCNFSM6AAAAAB5G5CB2WVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQOBZGEYDCMRVGA> . You are receiving this because you authored the thread.Message ID: ***@***.***>