Take a planet like Gliese 1214 B, which has no land, an ocean 100s of kilometres deep and a seabed of Ice VII. For the purposes of the question, let's assume that the pressure and/or temperature near the bottom makes it simply impossible for any form of life to survive. Maybe it does.
Of all the plausible posited models for abiogenesis, excluding panspermia, could any occur in these conditions? If the deep truly is uninhabitable, then abiogenesis will have to happen without any solid seabed, and therefore without hydrothermal vents, clay etc.