diff mbox series

kselftest: fix OOM in memory compaction test

Message ID 20180109162648.3987382-1-arnd@arndb.de
State Accepted
Commit 4c1baad223906943b595a887305f2e8124821dad
Headers show
Series kselftest: fix OOM in memory compaction test | expand

Commit Message

Arnd Bergmann Jan. 9, 2018, 4:26 p.m. UTC
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>

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

-- 
2.9.0
diff mbox series

Patch

diff --git a/tools/testing/selftests/vm/compaction_test.c b/tools/testing/selftests/vm/compaction_test.c
index a65b016d4c13..1097f04e4d80 100644
--- a/tools/testing/selftests/vm/compaction_test.c
+++ b/tools/testing/selftests/vm/compaction_test.c
@@ -137,6 +137,8 @@  int check_compaction(unsigned long mem_free, unsigned int hugepage_size)
 	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");