[MAINTAINERS SUMMIT] re-think of richACLs in AI/LLM era

["Coly Li" <colyli@fnnas.com>]

Hi folks,

This is Coly Li. I’ve been maintaining bcache for a while and have met Linus,
Greg, Ted, and other maintainers in person at many conferences. Yes, I am a
sustained and reliable kernel developer.

Recently, I joined a startup (https://fnnas.com) that provides AI/LLM
capabilities for personal or micro-enterprise storage. We help users share and
communicate AI/LLM-processed information from their stored data more
conveniently.

Our users can run highly compact LLMs on their own normal and inexpensive
hardware to process photos, videos, and documents using AI. Of course, it’s slow
but that’s expected and acceptable. They can even come back to check the results
weeks later.

In our use case, different people or roles store their personal and sensitive
data in the same storage pool, with different access controls granted to AI/LLM
processing tasks. When they share specific information or data with others
within the same machine or over the internet, the access control hierarchy or
rules become highly complicated and impossible to handle with POSIX ACLs.

We tried bypassing access control to user space, which worked well except for
scalability and performance:
- As the number and size of files increase, storing all access control rules in
  user space memory doesn’t scale—especially on normal machines without huge
  memory resources.
- For some hot data sets (a group of files and directories), checking access
  control rules in user space and hooking back to the kernel is highly
  inefficient.

Therefore, the RichACL project comes back to mind. Of course, RichACL alone
isn’t enough. A high-level policy agent (in user space) is still needed for
task/session-oriented access and sharing policy control, but RichACL can help
implement file system-level access control. This would give us a context-aware
and highly efficient access control implementation.

What I’d like to discuss is:
- After almost 10 years, should we reconsider RichACL in the AI/LLM era?
- What are the major barriers or remaining work needed to get RichACLs into
  upstream?

Since our first public beta was released 13 months ago, we now have over one-
million active installations running daily. This is a real workload for RichACL
and represents real feature demand from end users. If you’re interested in this
topic, we’d be happy to provide more details about the access control
requirements in AI workloads and even show a live demo of the use case.

Thanks in advance.

Coly Li