FreeBSD NFSv4.1/4.2 server is broken when Linux mounts use "nconnects"

[Rick Macklem]

Hi,

The FreeBSD NFS server is broken when handling multiple
connections for NFSv4.1/4.2.
It incorrectly binds the back channel to a new connection
when is sees an RPC with Sequence in it (almost all RPCs)
and might send a callback on the wrong connection.

I have a fix, but it won't be in a release until 12.3/13.1.
It can be found in Bugzilla PR#254560.

In the meantime, avoid using the "nconnects" option
on Linux client mounts.

Thanks go to Ben Coddington @redhat for diagnosing
this and testing the patch.

Sorry about the breakage, rick
ps: It was done intentionally long ago, when clients
      did not do BindConnectionToSession and then slipped
      through the cracks.