9.3 NFS client bug?

[Garrett Wollman]

I've been doing some NFS testing, and found some issues with the NFS
client in 9.3.  This is pretty easily reproducible with bonnie++, but
I haven't tried to reduce the size of the workload to make it easier
to test or trace.

##### NFSv3 mount, 9.3 client from 9.3 server
# bonnie++ -s 0 -n 1024:65536:0:1023:16384 -u 4294967294 -D
Using uid:-2, gid:65533.
Create files in sequential order...done.
Stat files in sequential order...done.
Delete files in sequential order...Bonnie: drastic I/O error (rmdir): Directory not empty
Cleaning up test directory after error.

Identical behavior is observed for a 9.3 client talking to a 9.1
server, and for NFSv4 mounts, but NOT for an Ubuntu 14.04 client
talking to the 9.3 server using either NFSv3 or NFSv4.

I haven't tried using a 9.2 or 9.1 client (yes, I still have some
machines running 9.1 here) to see if the issue is a recently
introduced one, nor have I traced the client or server code to see
what's actually going on.

Has anyone seen this before?

-GAWollman