We faced a crash on printing the information about the OOM timeout
because of a stale pointer in ctx->victim, looks like mark_oom_victim()
and oom_unlock() were called for a process already in do_exit() after
exit_oom_victim() call.
We have fixed the race, but as this message is not so useful, let
Currently it's possible to mark a task as a victim even in case it has
already cleared its ->mm.
This might lead (and leads) to a situation when oom_unlock() believes
the OOM context will be released by the "victim" do_exit() ->
exit_oom_victim(), but our "victim" already passed the point of calli
