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Description of problem:

the filesystem number from ACFS (0x61636673) is not listed in coreutils on RHEL6

Version-Release number of selected component (if applicable):

coreutils 

How reproducible:

run e.g. tail on a file residing on ACFS

Steps to Reproduce:
1. # tail -f test.log

Actual results:

hoge
fuga
tail: unrecognized file system type 0x61636673 for `test.log'. Reverting to 
polling.

Expected results:

known filesystem type

As an upstream report reference - debbugs.gnu.org/cgi/bugreport.cgi?bug=21876 ... with http://debbugs.gnu.org/cgi/bugreport.cgi?msg=10;filename=stat-new-fs-types.patch;att=1;bug=21876 as a patch by Pádraig Brady. Thanks Pádraig.

Note this file system is out of kernel tree.
Also newer versions of tail will not warn about this.
In any case this definition has been added to upstream at:
http://git.sv.gnu.org/gitweb/?p=coreutils.git;a=commitdiff;h=v8.24-83-g0daa359

Patch coreutils-8.4-tailstatnewfs2.patch is present in coreutils-8.4-42.el6.
This patch introduces all new FS recognized by upstream.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2016-0906.html