On 2017/10/05 3:59, Johannes Weiner wrote: > But the justification to make that vmalloc() call fail like this isn't > convincing, either. The patch mentions an OOM victim exhausting the > memory reserves and thus deadlocking the machine. But the OOM killer > is only one, improbable source of fatal signals. It doesn't make sense > to fail allocations preemptively with plenty of memory in most cases.
By the time the current thread reaches do_exit(), fatal_signal_pending(current) should become false. As far as I can guess, the source of fatal signal will be tty_signal_session_leader(tty, exit_session) which is called just before tty_ldisc_hangup(tty, cons_filp != NULL) rather than the OOM killer. I don't know whether it is possible to make fatal_signal_pending(current) true inside do_exit() though...