long-term stable backports of NFSD patches

[Chuck Lever <chuck.lever@oracle.com>]

It's apparent that a number of distributions and their customers
remain on long-term stable kernels. We are aware of the scalability
problems and other bugs in NFSD in kernels between v5.4 and v6.1.
 
Therefore I've started an effort to backport all NFSD commits to
those kernels. The backported commits are destined for the official
LTS kernel branches so that distributions can easily integrate them
into their products.

Here's a status update.

---

I've pushed the NFSD backports to branches in this repo:

https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git

If you are able, I encourage you to pull these, review them or try
them out, and report any issues or successes. I'm currently using
the NFS workflows in kdevops as the testing platform, but am
planning to include other tests.


LTS v6.1.y

Greg told me this morning that these are now queued for the next
LTS 6.1.y release.


LTS v5.15.y

I have updated this branch to include commits from v6.2.16 through
v5.16, all applied to v5.15.150. The fixes include most NFSD and
fanotify patches in that range. I've begun testing this series, and
so far the backport looks successful.

You can find these patches in the "nfsd-5.15.y" branch in the above
repo.


LTS v5.10.y

Backporting is still under way. I've gotten up to v6.0, and plan
to continue to v6.2.16. The fixes include most NFSD and fanotify
patches in that range, but exclude some because v5.10.y does not
include the VFS ID mapping patches that were merged into v5.12.

You can find these patches in the "nfsd-5.10.y" branch in the above
repo.


LTS v5.4.y

At this time I am planning not to backport to 5.4.y because of
missing features in this kernel.


-- 
Chuck Lever