Patch "shmem: fix compilation warnings on unused functions" has been added to the 4.9-stable tree

Patch "shmem: fix compilation warnings on unused functions" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    shmem: fix compilation warnings on unused functions

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     shmem-fix-compilation-warnings-on-unused-functions.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From f1f5929cd9715c1cdfe07a890f12ac7d2c5304ec Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=A9my=20Lefaure?= <jeremy.lefaure@lse.epita.fr>
Date: Mon, 12 Dec 2016 16:43:23 -0800
Subject: shmem: fix compilation warnings on unused functions
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Jérémy Lefaure <jeremy.lefaure@lse.epita.fr>

commit f1f5929cd9715c1cdfe07a890f12ac7d2c5304ec upstream.

Compiling shmem.c with SHMEM and TRANSAPRENT_HUGE_PAGECACHE enabled
raises warnings on two unused functions when CONFIG_TMPFS and
CONFIG_SYSFS are both disabled:

  mm/shmem.c:390:20: warning: `shmem_format_huge' defined but not used [-Wunused-function]
   static const char *shmem_format_huge(int huge)
                      ^~~~~~~~~~~~~~~~~
  mm/shmem.c:373:12: warning: `shmem_parse_huge' defined but not used [-Wunused-function]
   static int shmem_parse_huge(const char *str)
               ^~~~~~~~~~~~~~~~

A conditional compilation on tmpfs or sysfs removes the warnings.

Link: http://lkml.kernel.org/r/20161118055749.11313-1-jeremy.lefaure@lse.epita.fr
Signed-off-by: Jérémy Lefaure <jeremy.lefaure@lse.epita.fr>
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 mm/shmem.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -370,6 +370,7 @@ static bool shmem_confirm_swap(struct ad
 
 int shmem_huge __read_mostly;
 
+#if defined(CONFIG_SYSFS) || defined(CONFIG_TMPFS)
 static int shmem_parse_huge(const char *str)
 {
 	if (!strcmp(str, "never"))
@@ -407,6 +408,7 @@ static const char *shmem_format_huge(int
 		return "bad_val";
 	}
 }
+#endif
 
 static unsigned long shmem_unused_huge_shrink(struct shmem_sb_info *sbinfo,
 		struct shrink_control *sc, unsigned long nr_to_split)


Patches currently in stable-queue which might be from jeremy.lefaure@lse.epita.fr are

queue-4.9/x86-vm86-fix-unused-variable-warning-if-thp-is-disabled.patch
queue-4.9/shmem-fix-compilation-warnings-on-unused-functions.patch
queue-4.9/usb-musb-fix-compilation-warning-on-unused-function.patch