Arch Linux

Matteus

Member

Registered: 2020-07-20

Posts: 2

Xrandr glitch on the connected part of the primary display

Hello everyone !

First of all, i'm new here and a french guy, so if my post is at the wrong place or my English not understandable, i apologize in advance.

I created my first Arch system from scratch and it work amazingly. As a developer, i wanted to plug a USB dualscreen to help me to code.

So i installed xrandr, displaylink, and the module udl.

[matt@arch-MattOAE ~]$ xrandr --listproviders
Providers: number : 3
Provider 0: id: 0x44 cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 3 outputs: 2 associated providers: 1 name:modesetting
Provider 1: id: 0x992 cap: 0x2, Sink Output crtcs: 1 outputs: 1 associated providers: 1 name:modesetting
Provider 2: id: 0x23f cap: 0x0 crtcs: 0 outputs: 0 associated providers: 0 name:NVIDIA-G0

$matt@arch-MattOAE ~]$ xrandr --setprovideroutputsource 1 0

$matt@arch-MattOAE ~]$  modprobe udl

$matt@arch-MattOAE ~]$  xrandr --current
...
DVI-I-2-1 connected 1920x1080+1920+0 (normal left inverted right x axis y axis) 344mm x 193mm                                                                                                                                                  
   1920x1080     59.99*+                                                                                                                                                                                                                       
   1280x1024     75.02    60.02                                                                                                                                                                                                                
   1366x768      60.00                                                                                                                                                                                                                         
   1024x768      75.03    70.07    60.00                                                                                                                                                                                                       
  1280x1024 (0x51) 108.000MHz +HSync +VSync                                                                                                                                                                                                    
        h: width  1280 start 1328 end 1440 total 1688 skew    0 clock  63.98KHz                                                                                                                                                                
        v: height 1024 start 1025 end 1028 total 1066           clock  60.02Hz
  1024x768 (0x62) 65.000MHz -HSync -VSync
        h: width  1024 start 1048 end 1184 total 1344 skew    0 clock  48.36KHz
        v: height  768 start  771 end  777 total  806           clock  60.00Hz

The problem is the one following:

i wanted to put my portable screen on the left in portrait mode. On doing that, my primary screen glitch whenever i move a window like this, specially on the side where the screen has been connected.
I tried to unplug the screen but the bug is still there after that.

Does someone has any clue why xrandr is having this issue ?

Thanks in advance everyone, i'll try to check by my side too !

Matt

Lone_Wolf

Member

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 11,920

Re: Xrandr glitch on the connected part of the primary display

Those outputs suggest you have a hybrid graphics system.

Provider 1: id: 0x992 cap: 0x2, Sink Output crtcs: 1 outputs: 1 associated providers: 1 name:modesetting

What does this correspond to ?

What CPU / integrated GPU are you using ?

Brand and model of the portable screen ?

---

Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

(A works at time B)  && (time C > time B ) ≠  (A works at time C)

Matteus

Member

Registered: 2020-07-20

Posts: 2

Re: Xrandr glitch on the connected part of the primary display

Hello Lone_Wolf,

thanks for your answer. As requested, here's my configuration:

- CPU > Intel(R) Pentium(R) CPU 4405U @ 2.10GHz
- Integrated GPU > HD Graphics 510 (Intel, VGA compatible controller with driver i915)
- Side GPU > NVidia GM108M [GeForce 930MX] (3D controller, driver nvidia)

I think the line

Provider 1: id: 0x992 cap: 0x2, Sink Output crtcs: 1 outputs: 1 associated providers: 1 name:modesetting

correspond to my USB screen ASUS MB169B+

I tried the last days to find something, unfortunately, nothing.
Even sometimes, when i use xrandr to change something, my computer crashes.

EDIT:

I unplugged my usb screen and tried

[matt@arch-MattOAE ~]$ xrandr --listproviders
Providers: number : 2
Provider 0: id: 0x44 cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 3 outputs: 2 associated providers: 0 name:modesetting
Provider 1: id: 0x23f cap: 0x0 crtcs: 0 outputs: 0 associated providers: 0 name:NVIDIA-G0

Last edited by Matteus (2020-07-29 09:07:41)

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,731

Re: Xrandr glitch on the connected part of the primary display

Afaik there's an issue with displaylink and modesettings pageflip mechanism

Section "OutputClass"
  Identifier "DisplayLink"
  MatchDriver "evdi" #Not sure here, double check with e.g. lsusb what the actual kernel driver for the displaylink device is
  Driver "modesetting"
  Option "PageFlip" "false"
EndSection 

might help.