Patch "kselftest: fix OOM in memory compaction test" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

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

    kselftest: fix OOM in memory compaction test

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:
     kselftest-fix-oom-in-memory-compaction-test.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 4c1baad223906943b595a887305f2e8124821dad Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <arnd@arndb.de>
Date: Tue, 9 Jan 2018 17:26:24 +0100
Subject: kselftest: fix OOM in memory compaction test

From: Arnd Bergmann <arnd@arndb.de>

commit 4c1baad223906943b595a887305f2e8124821dad upstream.

Running the compaction_test sometimes results in out-of-memory
failures. When I debugged this, it turned out that the code to
reset the number of hugepages to the initial value is simply
broken since we write into an open sysctl file descriptor
multiple times without seeking back to the start.

Adding the lseek here fixes the problem.

Cc: stable@vger.kernel.org
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Link: https://bugs.linaro.org/show_bug.cgi?id=3145
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 tools/testing/selftests/vm/compaction_test.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/tools/testing/selftests/vm/compaction_test.c
+++ b/tools/testing/selftests/vm/compaction_test.c
@@ -136,6 +136,8 @@ int check_compaction(unsigned long mem_f
 	printf("No of huge pages allocated = %d\n",
 	       (atoi(nr_hugepages)));
 
+	lseek(fd, 0, SEEK_SET);
+
 	if (write(fd, initial_nr_hugepages, strlen(initial_nr_hugepages))
 	    != strlen(initial_nr_hugepages)) {
 		perror("Failed to write value to /proc/sys/vm/nr_hugepages\n");


Patches currently in stable-queue which might be from arnd@arndb.de are

queue-4.9/kselftest-fix-oom-in-memory-compaction-test.patch