kselftest: fix OOM in memory compaction test

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>
This commit is contained in:
Arnd Bergmann 2018-01-09 17:26:24 +01:00 committed by Shuah Khan
parent 912ec31668
commit 4c1baad223
1 changed files with 2 additions and 0 deletions

View File

@ -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");