Created attachment 338485 [details]
patch taken from opensuse

Description of problem:
In recent version of X server, DontZap changed it's default value, so ctrl+alt+backspace doesn't work anymore in default configuration. Main reason for changing the default value was because of accidental killing X server. I think warning before X server is killed should be enough. This way was also chosen for example in opensuse.

I know, it's usually suggested to change vt, log in and kill it from the terminal, but there are cases when something is consuming lot of resources in a loop so you definitely have no time to do all that steps, but using c+a+bs immediately helps.

Thanks