final edit: You want real logs instead? add this to your kernel command: drm.panic_screen=kmsg

Kinda funny, kinda neat.

I have no idea what the QR-code might reveal (I could not read it from this picture), so I pixelised it just to be sure.

FWIW I know exactly what happened and did not panic. To reproduce, boot your device with init=/bin/sh, then type exit.

CachyOS

The picture above is generated by Drm panic which is part of the kernel itself, or maybe a separate module. The data in the QR code is the kmsg log.

Not systemd, which wasn’t running when that happened.

And it’s been around for years; I guess I haven’t had a kernel panic in a long time.

  • SteveTech@aussie.zone
    1·
    12 hours ago

    Switching ttys wouldn’t have done anything. The kernel logs are usually saved to efi_pstore (or sometimes erst) by default though.

    Edit: you can also set drm.panic_screen=kmsg as a kernel parameter to print the logs instead of the QR.

    • A_norny_mousse@piefed.zipOPEnglish
      21·
      5 hours ago

      👍

      Drm panic provides different panic screens. The default is “user” which will display a simple friendly message telling the user to reboot the computer. But for kernel developers, you can also set it to “kmsg”, to see the last kmsg lines (so this is equivalent to the current fbcon). You can select the panic screen in Kconfig, or as a module parameter (drm.panic_screen=user) or at runtime with “echo -n kmsg > /sys/module/drm/parameters/panic_screen”

      (source)

      In other words, cat /sys/module/drm/parameters/panic_screen will show you what the current status is.