Bug 461708 - External monitor through HDMI - USB-C adapter detected, but gives black screen after login
Summary: External monitor through HDMI - USB-C adapter detected, but gives black scree...
Status: RESOLVED WORKSFORME
Alias: None
Product: kwin
Classification: Plasma
Component: multi-screen (show other bugs)
Version: 5.24.6
Platform: Kubuntu Linux
: NOR normal
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords: multiscreen
Depends on:
Blocks:
 
Reported: 2022-11-11 19:20 UTC by andre.maz.90
Modified: 2024-08-29 03:47 UTC (History)
5 users (show)

See Also:
Latest Commit:
Version Fixed In:
Sentry Crash Report:


Attachments
Display is shown in the "Devices" tab but it's not possible to configure it (249.96 KB, image/png)
2022-11-11 19:20 UTC, andre.maz.90
Details

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Description andre.maz.90 2022-11-11 19:20:54 UTC
Created attachment 153679 [details]
Display is shown in the "Devices" tab but it's not possible to configure it

SUMMARY
***
NOTE: If you are reporting a crash, please try to attach a backtrace with debug symbols.
See https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports
***

I'm facing a problem with my external display (connected via USB-C). It properly detected during the boot and when asking for credentials to login. However after the login the external screen goes black and it's not shown in the "Display and Config" tab. For more context please see the video: https://www.youtube.com/watch?v=vKxg4BjhoVA

The screen is detected by the xrandr, here's the result
```
xrandr -q
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 16384 x 16384
eDP connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 310mm x 174mm
   2560x1440    120.00 +  60.00  
   1920x1200    120.00  
   1920x1080    120.00* 
   1600x1200    120.00  
   1680x1050    120.00  
   1280x1024    120.00  
   1440x900     120.00  
   1280x800     120.00  
   1280x720     120.00  
   1024x768     120.00  
   800x600      120.00  
   640x480      120.00  
HDMI-A-0 disconnected (normal left inverted right x axis y axis)
DP-1-0.1 connected (normal left inverted right x axis y axis)
   1920x1080     60.00 +  59.94    50.00  
   1680x1050     59.95  
   1440x900      59.89  
   1440x576      50.00  
   1440x480      59.94  
   1280x1024     75.02    60.02  
   1280x960      60.00  
   1280x720      60.00    59.94    50.00  
   1152x864      75.00  
   1024x768      75.03    70.07    60.00  
   800x600       75.00    72.19    60.32    56.25  
   720x576       50.00  
   720x480       59.94  
   640x480       75.00    72.81    59.94    59.93  
DP-1-0 disconnected (normal left inverted right x axis y axis)
DP-1-1 disconnected (normal left inverted right x axis y axis)
```

OBSERVED RESULT
Not able to configure the external screen.

EXPECTED RESULT
To be able to configure the external screen.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Kubuntu LTS 22.04
(available in About System)
KDE Plasma Version: 5.24.6
KDE Frameworks Version: 5.92.0 
Qt Version: 5.15.3

ADDITIONAL INFORMATION
Laptop Model: Asus ROG Zephyrus G14 GA401QE
CPU: Ryzen 5900HS
GPU: Nvidia 3050 Ti
NVidia drivers info: Driver Version: 520.56.06    CUDA Version: 11.8
Comment 1 Nate Graham 2022-11-12 14:16:02 UTC
The screenshot and screen recording indicate that KScreen can see the screen--or else it wouldn't appear as an entry in the combobox.

If you click on its entry in the combobox, do you see that the "Enabled" checkbox is unchecked? If so, if you check it and then click apply, does the screen turn on again?

If so, this is Bug 460341.
Comment 2 andre.maz.90 2022-11-12 15:23:00 UTC
(In reply to Nate Graham from comment #1)
> The screenshot and screen recording indicate that KScreen can see the
> screen--or else it wouldn't appear as an entry in the combobox.
> 
> If you click on its entry in the combobox, do you see that the "Enabled"
> checkbox is unchecked? If so, if you check it and then click apply, does the
> screen turn on again?
> 
> If so, this is Bug 460341.


When I click on "Enabled" and hit apply the screen is still black. Moreover, the entire system becomes unstable. The mouse cursor lags a lot and the screen freezes for several seconds.
Comment 3 Nate Graham 2022-11-12 15:25:13 UTC
Ok thanks. That makes this either a KWin bug or an NVIDIA driver bug; moving to KWin to start with. I suspect it will ultimately end up being an NVIDIA driver bug though...
Comment 4 andre.maz.90 2022-11-12 15:36:32 UTC
(In reply to Nate Graham from comment #3)
> Ok thanks. That makes this either a KWin bug or an NVIDIA driver bug; moving
> to KWin to start with. I suspect it will ultimately end up being an NVIDIA
> driver bug though...

Thank you for quick response. I also suspect that it might be a bug on NVIDIA's side and I've also opened an issue in their forums.

I've added a basic `20-nvidia.conf` to `etc/X11/xorg.conf.d` 

```
/etc/X11/xorg.conf.d$ cat 20-nvidia.conf 
Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BusID          "PCI:1:0:0"
EndSection
```
and now my external screens is working. However, now the laptop screen goes black. 

Here's the result for the `xrandr -q` with custom `20-nvidia.conf ` (Note: I have 2 external monitors connected via USB-C)
```
Screen 0: minimum 8 x 8, current 3840 x 1080, maximum 32767 x 32767
DP-0.1 connected primary 1920x1080+1920+0 (normal left inverted right x axis y axis) 531mm x 298mm
   1920x1080     60.00*+  59.94    50.00  
   1680x1050     59.95  
   1600x900      60.00  
   1280x1024     75.02    60.02  
   1280x800      59.81  
   1280x720      60.00    59.94    50.00  
   1024x768      75.03    60.00  
   800x600       75.00    60.32  
   720x576       50.00  
   720x480       59.94  
   640x480       75.00    59.94    59.93  
DP-0.2 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 531mm x 298mm
   1920x1080     60.00*+  59.94    50.00  
   1680x1050     59.95  
   1600x900      60.00  
   1280x1024     75.02    60.02  
   1280x800      59.81  
   1280x720      60.00    59.94    50.00  
   1024x768      75.03    60.00  
   800x600       75.00    60.32  
   720x576       50.00  
   720x480       59.94  
   640x480       75.00    59.94    59.93  
DP-0 disconnected (normal left inverted right x axis y axis)
DP-1 disconnected (normal left inverted right x axis y axis)
```

For some reason the `xrandr --listproviders` only shows the NVIDIA GPU and doesn't show the AMD's iGPU
```
Providers: number : 1
Provider 0: id: 0x1b7 cap: 0x1, Source Output crtcs: 4 outputs: 4 associated providers: 0 name:NVIDIA-0
```

However, when running `lshw -C display` I get the following info:

```
*-display                 
       description: VGA compatible controller
       product: GA107M [GeForce RTX 3050 Ti Mobile]
       vendor: NVIDIA Corporation
       physical id: 0
       bus info: pci@0000:01:00.0
       logical name: /dev/fb0
       version: a1
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress vga_controller bus_master cap_list rom fb
       configuration: depth=32 driver=nvidia latency=0 mode=2560x1440 visual=truecolor xres=2560 yres=1440
       resources: iomemory:fe0-fdf iomemory:ff0-fef irq:79 memory:fb000000-fbffffff memory:fe00000000-feffffffff memory:ff00000000-ff01ffffff ioport:e000(size=128) memory:fc000000-fc07ffff
  *-display
       description: VGA compatible controller
       product: Cezanne
       vendor: Advanced Micro Devices, Inc. [AMD/ATI]
       physical id: 0
       bus info: pci@0000:04:00.0
       logical name: /dev/fb0
       version: c4
       width: 64 bits
       clock: 33MHz
       capabilities: pm pciexpress msi msix vga_controller bus_master cap_list fb
       configuration: depth=32 driver=amdgpu latency=0 resolution=2560,1440
       resources: iomemory:ff0-fef iomemory:ff0-fef irq:46 memory:ff10000000-ff1fffffff memory:ff20000000-ff201fffff ioport:d000(size=256) memory:fc500000-fc57ffff
```
Comment 5 Kangarooo 2022-12-17 21:52:31 UTC
Does running this in terminal fixes?
xrandr -q
Comment 6 Michael Butash 2022-12-18 05:32:58 UTC
I've been fighting with what sounds similar since doing a full arch upgrade a week ago, this is currently with kernel 6.0.11 and nvidia 525.60.11-2 and plasma/kwin 5.26.4, using either an older CalDigit TB3 dock or my Lenovo TB4 pro dock with two/three hdmi displays normally, but only been able to get one to work since the last upgrade.  This pulled in latest nvidia drivers, broke everything while using an lts kernel still, so ended up moving to latest, which got it working again eventually resetting with nvidia-settings, but no matter the dock or display or cables, I can only get one display to actually activate at a time.  Even xrandr shows the displays like yours, kde settings show them, only it's doesn't seem to actually activate the display enabling them on/off, and I don't get the display reset countdown now with 2 or 3 external displays plugged in on either dock.  Even trying to use nvidia settings does roughly the same, so I don't think it's entirely a KDE problem.  Really annoying being reduced to only one external display at the moment, but I couldn't even get that at first with newer drivers.
Comment 7 Nate Graham 2022-12-23 22:08:19 UTC
Worth re-testing with the upcoming Plasma 5.27, where we did a major multiscreen refactor. I'd say there's a chance this is fixed now.
Comment 8 Zamundaaa 2024-07-30 09:24:09 UTC
Do you still experience this with Plasma 6?
Comment 9 Bug Janitor Service 2024-08-14 03:46:49 UTC
🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!
Comment 10 Bug Janitor Service 2024-08-29 03:47:56 UTC
🐛🧹 This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.