OK. I think I figured this one out.
If one installs console-cyrillic package and selects Unicode (utf-8) input and enables it at boot time, then the script "cyr" executes 'kbd_mode -u' at startup, whith /dev/console as the standard input. Running 'kdb_mode -u /dev/console' at any time triggers this bug.
This is probably a problem in kbd_mode program of package kbd, which should not break the keyboard in X session.
But in any case, the cyr script should apply mode change to all configured consoles, not to the one which happens to be its stdin.
So, here is the patch for /usr/bin/cyr.
The script is tested on Ubunut 10.10, with console-cyrillic 0.9-16 and kbd 1.15-1ubuntu3.
OK. I think I figured this one out.
If one installs console-cyrillic package and selects Unicode (utf-8) input and enables it at boot time, then the script "cyr" executes 'kbd_mode -u' at startup, whith /dev/console as the standard input. Running 'kdb_mode -u /dev/console' at any time triggers this bug.
This is probably a problem in kbd_mode program of package kbd, which should not break the keyboard in X session.
But in any case, the cyr script should apply mode change to all configured consoles, not to the one which happens to be its stdin.
So, here is the patch for /usr/bin/cyr.
The script is tested on Ubunut 10.10, with console-cyrillic 0.9-16 and kbd 1.15-1ubuntu3.