tmpfs: expand "help" to explain value of TMPFS_POSIX_ACL

Expand the fs/Kconfig "help" info to clarify why it's a bad idea to
deselect the TMPFS_POSIX_ACL config variable.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 11 insertions, 4 deletions

diff --git a/fs/Kconfig b/fs/Kconfig
index 19891aab9c6e..9fe0b349f4cd 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -127,14 +127,21 @@ config TMPFS_POSIX_ACL
         select TMPFS_XATTR
         select GENERIC_ACL
         help
-          POSIX Access Control Lists (ACLs) support permissions for users and
-          groups beyond the owner/group/world scheme.
+          POSIX Access Control Lists (ACLs) support additional access rights
+          for users and groups beyond the standard owner/group/world scheme,
+          and this option selects support for ACLs specifically for tmpfs
+          filesystems.
+
+          If you've selected TMPFS, it's possible that you'll also need
+          this option as there are a number of Linux distros that require
+          POSIX ACL support under /dev for certain features to work properly.
+          For example, some distros need this feature for ALSA-related /dev
+          files for sound to work properly.  In short, if you're not sure,
+          say Y.
 
           To learn more about Access Control Lists, visit the POSIX ACLs for
           Linux website <http://acl.bestbits.at/>.
 
-          If you don't know what Access Control Lists are, say N.
-
 config TMPFS_XATTR
         bool "Tmpfs extended attributes"
         depends on TMPFS