On Mon, Nov 29, 2021 at 6:07 PM Greg Kroah-Hartman
[off-list ref] wrote:

...
Sometimes, yes, it is valid to have different implementations for things
that do different things in the same area (like filesystems), but for a
core function of the kernel, so far the existing random maintainer has
not wanted to have multiple implementations.  Same goes for other parts
of the kernel, it's not specific only to this one very tiny driver.

As a counterpoint, we do not allow duplicate drivers that control the
same hardware types in the tree.  We have tried that in the past and it
was a nightmare to support and maintain and just caused massive user
confusion as well.  One can argue that the random driver is in this same
category.

I think an argument could be made that they are different drivers
since they have different requirements and security goals. I don't
think it matters where the requirements came from, whether it was ad
hoc from the developer, NIST, KISA, CRYPTREC, NESSIE, or another
organization.

Maybe the problem is with the name of the driver? Perhaps the current
driver should be named random-linux, Stephan's driver should be named
random-nist, and the driver should be wired up based on a user's
selection. That should sidestep the problems associated with the
"duplicate drivers" policy.

Jeff