When a slave crashes for whatever reason we get a backtrace in the log but often we don't kill the greeter associated with it or the helper processes.  In addition to that we don't try to switch the active session to ensure the user doesn't get left at a dead end.

Not killing the workers may leave PAM login devices such as smartcards in an unusable state for the next login attempt.


On IRC, Ray suggests using the following on Linux:
 prctl(PR_SET_PDEATHSIG,unsigned long arg2, unsigned long arg3, unsigned long arg4, unsigned long arg5);