Well, a primordial soup doesn't BECOME a living cell. A living cell arises WITHIN a "primordial soup" so-called.
Current theory, as far as I understand it, posits an "RNA world" which existed for some hundreds of millions of years, in which DNA did not exist, and the unit of selection by "survival of the fittest" was not an organism, but merely a codon. The Ebola virus exemplifies the type of fitness that was rewarded, and obviously still is.
I'm no expert, but this is deep sh*t.