#939079 nouveau: screen dimensions and resolution are wrong

Package:
src:linux
Source:
linux
Submitter:
Vincent Lefevre
Date:
2025-05-03 11:30:01 UTC
Severity:
normal
Tags:
#939079#5
Date:
2019-09-01 02:11:15 UTC
From:
To:
With the nouveau driver, I get:

$ xdpyinfo
[...]
screen #0:
  dimensions:    3200x1800 pixels (846x476 millimeters)
  resolution:    96x96 dots per inch
[...]

which is wrong!

As a comparison, with the nvidia driver:

[...]
screen #0:
  dimensions:    3200x1800 pixels (350x191 millimeters)
  resolution:    232x239 dots per inch
[...]

which is correct.

This prevents HiDPI detection.
#939079#10
Date:
2023-10-10 11:59:00 UTC
From:
To:
Control: found -1 6.1.55-1

After installing Debian 12 (bookworm) on a new laptop, without the
nvidia driver, I can see the same issue.

screen #0:
  dimensions:    3840x2400 pixels (1016x635 millimeters)
  resolution:    96x96 dots per inch

For such a laptop, the dimensions and resulting resolution are
obviously wrong.
#939079#17
Date:
2025-02-20 11:25:48 UTC
From:
To:
Hi

This bug was filed for a very old kernel or the bug is old itself
without resolution.

If you can reproduce it with

- the current version in unstable/testing
- the latest kernel from backports

please reopen the bug, see https://www.debian.org/Bugs/server-control
for details.

Regards,
Salvatore
#939079#20
Date:
2025-02-20 11:25:48 UTC
From:
To:
Hi

This bug was filed for a very old kernel or the bug is old itself
without resolution.

If you can reproduce it with

- the current version in unstable/testing
- the latest kernel from backports

please reopen the bug, see https://www.debian.org/Bugs/server-control
for details.

Regards,
Salvatore
#939079#25
Date:
2025-02-20 12:49:23 UTC
From:
To:
Same laptop as in 2023, with 2 external monitors, xdpyinfo says:

screen #0:
  dimensions:    7680x2160 pixels (2032x571 millimeters)
  resolution:    96x96 dots per inch

but xrandr gives the correct dimensions of the individual screens:

  697mm x 392mm
  597mm x 336mm
#939079#34
Date:
2025-05-01 12:33:19 UTC
From:
To:
Hi Vincent,

Since you are able to reproduce it with a fresh kernel, can you please
report the issue upstream (please keep us in the loop so we can
monitor the progress).

Thank you!

Regards,
Salvatore
#939079#41
Date:
2025-05-02 23:12:45 UTC
From:
To:
Control: forwarded -1 https://gitlab.freedesktop.org/xorg/xserver/-/issues/49

The bug had actually been reported at least 4 - 5 times, the first
ones in 2008. The 5th bug report is about XWayland/xdpyinfo, but
this seems to be the same issue.

I've forwarded this bug to what seems to be the best upstream one.

I've added a comment there, with references to the other 4 bugs.
#939079#48
Date:
2025-05-03 11:28:26 UTC
From:
To:
Hi Vincent,

Thank you!

Regards,
Salvatore