Arch Linux

hoschi

Member

From: Ulm (Germany)

Registered: 2008-11-03

Posts: 468

Switching TTYs with active framebuffer doesn't work with kernel >= 5.7

Hello!

I want to check if this is an general issue or only affecting Intel graphics. When I view a picture with fbi it loads and displays, but I'm not able to switch the display to another VT (Alt+Fn or Alt+Arrow Left/Right). To be precise, the VT switches actually and keyboard input is send to the selected VT - but the image stays on the screen.

If you don't use fbi, you can also check it likely with mpv or mplayer.

Thanks

Ropid

Member

Registered: 2015-03-09

Posts: 1,069

Re: Switching TTYs with active framebuffer doesn't work with kernel >= 5.7

I see the same here when trying this "fbi" program. I can't switch to another tty while it is running and displaying an image.

This is with AMD graphics. My GPU is an RX480, it uses the "amdgpu" kernel module.

I tried testing this with mpv as well, but with mpv I can change ttys. I started mpv with a command line "mpv --vo=drm filename".

tpfkanep

Member

From: South Africa

Registered: 2009-12-15

Posts: 127

Re: Switching TTYs with active framebuffer doesn't work with kernel >= 5.7

Only "workaround" I could find, is to switch back to the "calling" TTY, and then repeat the process (this is using Intel with i3):

- TTY1 (with i3)
- [Ctrl] + [Alt] + [F2]
- i3 on screen?
- [Alt] + [F1] (TTY1 with i3)
- [Ctrl] + [Alt] + [F2]

Edit: Zen kernel exhibits the same behaviour.

Last edited by tpfkanep (2020-06-12 14:09:00)

hoschi

Member

From: Ulm (Germany)

Registered: 2008-11-03

Posts: 468

Re: Switching TTYs with active framebuffer doesn't work with kernel >= 5.7

Thanks people. Upstream already mentioned a change for the fbcon modesetting client, but that was back in "5.6"

// edit
We got a suspect.

Last edited by hoschi (2020-06-13 10:39:39)

hoschi

Member

From: Ulm (Germany)

Registered: 2008-11-03

Posts: 468

Re: Switching TTYs with active framebuffer doesn't work with kernel >= 5.7

Fixed with linux 5.7.7 for me
My guess it is this.

Last edited by hoschi (2020-07-03 12:04:13)