Comment 16 for bug 1654708

This was fixed with:

zfs-linux (0.6.5.6-0ubuntu16) xenial; urgency=medium

  * Enable zfs to respect RSIZE_LIMIT limits (LP: #1656259)
    - backport of zfs upstream commit 4b908d32200b6e5c7b5115322b6c8d25e770daa0
      ("Linux 4.8 compat: posix_acl_valid()") to facilitate changes in posix_acl_valid.
      1015-Linux-4.8-compat-posix_acl_valid.patch
    - backport of upstream commit 933ec999511f3d29de005bfa8966ae007b161c0f
      ("Retire .write/.read file operations")
      1016-Retire-.write-.read-file-operations.patch

with upstream commit:

commit 4b908d32200b6e5c7b5115322b6c8d25e770daa0
Author: Brian Behlendorf <email address hidden>
Date: Tue Aug 2 11:11:45 2016 -0700

    Linux 4.8 compat: posix_acl_valid()

    The posix_acl_valid() function has been updated to require a
    user namespace. Filesystem callers should normally provide the
    user_ns from the super block associcated with the ACL; the
    zpl_posix_acl_valid() wrapper has been added for this purpose.
    See https://github.com/torvalds/linux/commit/0d4d717f for
    complete details.

    Signed-off-by: Brian Behlendorf <email address hidden>
    Signed-off-by: Nikolay Borisov <email address hidden>
    Signed-off-by: Chunwei Chen <email address hidden>
    Closes #4922

https://github.com/zfsonlinux/zfs/pull/4922