You are not logged in.

#1 2016-09-21 21:49:47

poinu
Member
Registered: 2016-05-09
Posts: 13

Yet another multi-head HiDPI misconfiguration problem

I've been reading the wiki articles as well as some related posts about HiDPI and/or multi-head in this very forum, I haven't been able to make it work yet.

My setup:

Laptop screen - QHD+ (3200 x 1800) - eDP1
External screen - FHD (1920x1080) - HDMI1

I am using gnome3 and gdm. I try to use xrandr to get both monitors working at the correct resolution side by side. When I issue the following command on a terminal, everything gets configured as expected, everything is working:

xrandr --output eDP1 --mode 3200x1800 --scale 1x1 --output HDMI1 --mode 1920x1080 --panning 3840x2160+3200+0 --scale 2x2

However, when I try to make it work automatically on startup, either by placing the previous line in ~/.xprofile or /etc/gdm/Xsession, the configuration gets overriden at some point afterwards. Here is the journalctl log:

Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: /etc/gdm/Xsession: Beginning session setup...
Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: localuser:ferran being added to access control list
Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: /etc/gdm/Xsession: Try to set up screen resolution...
Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: xrandr: Output DP1 is not disconnected but has no modes
Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: (II) intel(0): resizing framebuffer to 7040x2160
Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: (II) intel(0): switch to mode 1920x1080@60.0 on HDMI1 using pipe 0, position (3200, 0), rotation normal, reflection none
Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: /etc/gdm/Xsession: Setup done, will execute: gnome-session
Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: (II) intel(0): EDID vendor "SHP", prod id 5153
Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: (II) intel(0): Printing DDC gathered Modelines:
Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: (II) intel(0): Modeline "3200x1800"x0.0  373.25  3200 3248 3280 3360  1800 1803 1808 1852 -hsync -vsync (111.1 kHz eP)
Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: (II) intel(0): resizing framebuffer to 5120x1800
Sep 21 23:23:16 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: (II) intel(0): switch to mode 1920x1080@60.0 on HDMI1 using pipe 0, position (3200, 0), rotation normal, reflection none

It seems to me that the log lines that come after "Setup done, will execute: gnome-session" override the correct configuration. Precisely, the line that resizes the framebuffer to 5120x1800 seems to break everything.

This is what appears to the log when I run the command manually on a terminal.

Sep 21 23:24:09 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: (II) intel(0): resizing framebuffer to 7680x3960
Sep 21 23:24:09 Ferran-Ultrabook /usr/lib/gdm/gdm-x-session[7507]: (II) intel(0): switch to mode 1920x1080@60.0 on HDMI1 using pipe 0, position (3200, 0), rotation normal, reflection none

I have also tried adding --fb 7680x3960 to the previous command, without any luck.

Any ideas on when in the startup process issues this framebuffer resize and why? Any other hint to get this working altogether?

Thank you!

Offline

Board footer

Powered by FluxBB