I can reproduce the problem only by running grub-emu as root. It is
reproducible in both the 2.02+dfsg1-20+deb10u2 (Buster) and 2.04-8
(current Bullseye).
The severity is not an exaggeration IMO as afterwards your machine
will be headless. Recovering with Alt+SysRq+k does not work; neither
does restarting the X server. I had to restart the machine every time
I ran grub-emu as root. If logging in remotely is not an option,
pressing "Alt+SysRq+r" and then "Ctrl+Alt+Del" at least 8 times in
quick succession should make systemd reboot the machine cleanly as
long as this feature was not disabled.
For debugging purposes I added this as the first entry in grub.cfg:
menuentry 'halt' {
set timeout=5
halt
}
In non-SDL-mode it makes "grub-emu" exit normally even without
pressing any keys.
I see at least two problems at play:
* grub-emu in SDL mode does not react in any way to key presses
after starting
* grub-emu in SDL mode does not restore the previous video mode even
after exiting normally using the above grub.cfg snippet.
I think only these options are realistic:
* have upstream fix the bug
* compile with --disable-grub-emu-sdl
* stop shipping grub-emu altogether
Unless someone stops me I'll file a bug in the upstream tracker for
this 14 days from now.
Regards,
Dennis.
