[PATCH v5 08/15] mm: Add unsafe_follow_pfn

[Christoph Hellwig]

On Fri, Oct 30, 2020 at 11:08:08AM +0100, Daniel Vetter wrote:
> Also mark up follow_pfn as EXPORT_SYMBOL_GPL. The only safe way to use
> that by drivers/modules is together with an mmu_notifier, and that's
> all _GPL stuff.

I also think it also needs to be renamed to explicitly break any existing
users out of tree or int the submission queue.