Re: [RFC] apfs: thoughts on upstreaming an out-of-tree module

["Ernesto A. Fernández" <ernesto.mnd.fernandez@gmail.com>]

Hi everyone,

I don't mind putting in the work to prepare my driver for upstream. I just
can't make a case for it myself, since it sounds like a lot of work for the
reviewers and I suspect it won't be all that useful in practice.

I think the driver is reliable enough under linux-only use; the subset of
xfstests that I managed to get to run stopped finding intermittent bugs last
year. I'm less confident about our compatibility with the official driver,
since I recently fixed a terrible corruption bug for all shared containers
above 1.32 TiB in size. There is an official reference for the layout, but
it's incomplete and has a few errors.

> > (Although I suspect many external SSD's would end
> > up using some other file system that might be more portable like VFS.)

That's what I would expect too. The driver does get cloned a lot, and it's
been packaged for debian for years, so I guess some people must be using it,
but I don't really know for sure.

> > In terms of making it work with the internal SSD, it sounds like Linux
> > would need to talk to the secure enclave on the T2 Security Chip and
> > convince it to upload the encryption key into the hardware in-line
> > encryption engine.

I don't know much about the hardware side, but I think my driver will also
need some changes to get this to work. Right now we don't support any form
of encryption. It's the biggest missing feature I believe.

Ernesto