fbset has no effect

I have added my username to the video group, and this allows me to open and use the /dev/fb0 device. So far so good.

But when I try to change the resolution using fbset(1) nothing happens. There are no errors, but there is no change of video mode either.

I use this on a virtual text console.

$ fbset -v 640x480-72
Linux Frame Buffer Device Configuration Version 2.1 (23/06/1999)
(C) Copyright 1995-1999 by Geert Uytterhoeven
Opening frame buffer device `/dev/fb0'
Reading mode database from file `/etc/fb.modes'
Using video mode `640x480-72'
Setting video mode to `/dev/fb0'
$

There are also no messages in /var/log/kern.log about this, either.

Why does the resolution change not happen?

NOTE: The rest of the framebuffer functionality works just fine. I can directly write pixels to it, which show up on screen. But the resolution is stuck at 1024x768-75. Running fbset as root doesn't help either.

During boot time, the kernel says:

[ 0.360247] efifb: probing for efifb
[ 0.360262] efifb: No BGRT, not showing boot graphics
[ 0.360264] efifb: framebuffer at 0xb0000000, using 3072k, total 3072k
[ 0.360266] efifb: mode is 1024x768x32, linelength=4096, pages=1
[ 0.360268] efifb: scrolling: redraw
[ 0.360269] efifb: Truecolor: size=8:8:8:8, shift=24:16:8:0
[ 0.360330] Console: switching to colour frame buffer device 128x48
[ 0.361439] fb0: EFI VGA frame buffer device

The framebuffer is EFI:

Frame buffer device information: Name : EFI VGA Address : 0xb0000000 Size : 3145728 Type : PACKED PIXELS Visual : TRUECOLOR XPanStep : 0 YPanStep : 0 YWrapStep : 0 LineLength : 4096 Accelerator : No

OS: Ubuntu 21.10

Kernel: 5.13.0-28-generic

GPU: RTX 3070

CPU: Xeon W-2140B

Reset to default

Know someone who can answer? Share a link to this question via email, Twitter, or Facebook.

Your Answer

Sign up or log in

Sign up using Google Sign up using Facebook Sign up using Email and Password

Post as a guest

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

You Might Also Like