From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759423AbeAIQ1H (ORCPT + 1 other); Tue, 9 Jan 2018 11:27:07 -0500 Received: from mout.kundenserver.de ([212.227.126.134]:50289 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759228AbeAIQ1D (ORCPT ); Tue, 9 Jan 2018 11:27:03 -0500 From: Arnd Bergmann To: Shuah Khan Cc: Sri Jayaramappa , Arnd Bergmann , stable@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] kselftest: fix OOM in memory compaction test Date: Tue, 9 Jan 2018 17:26:24 +0100 Message-Id: <20180109162648.3987382-1-arnd@arndb.de> X-Mailer: git-send-email 2.9.0 X-Provags-ID: V03:K0:3yxd9CYeNCHKUdhE/S2DMQiX4sOuzMzuqWQFhY/OyS7jQhGy2mX 1TChPM6c2uJqoHJTfa9r4jfkevvhGMfm+QCzvsAuCwa0olPm/SjS4FkPIjL3+o7n089BkWs htOiR6nTD+cxTuXb7oH92V2XbimxF1l72DV/tnjhbUOoq4J0sdsvhiiYpcT3Sf0/qHblzHk J9OBiZepAgnEx5G5bIeAg== X-UI-Out-Filterresults: notjunk:1;V01:K0:uLxZ8IyjvD4=:ADI19cRpapI6nwmoywKjKJ p3lH0ipWvn88nzdapXJ7eHX7KXo9HHoEKICzuplXNCJ8f2kfes8tJMD1ND6jS1WV+BMkUb0t/ mQMuMQqGpEMZDk0eDw9ubYFsxj+P9U6D9ii7Gso7xu4Y+2cQTyV0ML8T0CEKHTg4gUHmrl4w1 7VYMLNWLPkSs9P54IbtqAHK6YLPA0XlNsBFll6BcTYKDfN36fAnGUOlp7xYKgNc+QIFZvjjRF lOr6mIiDuD7vjP5bi+eODnVZIAGQLBQywaKE1nXErfit527C2WSAH1zIlAUiH76b9rElhz+ih Cm/c+fJIfumSxllTPba8GfFEY7mIwc0+ujvjwDO7VRzl9+lbnoCyj44dA6yV1JnrBAfpnIxlk Dtq+HC3xevIzFAs3MlJBDm+htuN/t9mPpHSTy2zDPVYX7+B7UrFX/HxY1q/oKYyUPbjFadtK5 dDJNneZ04uG3yXKDxupIJHXspcQVRBn+YKY5DqLhM9M5E92ONCNrkxsi95K9ewcWIV0ajZwac 2n/Ex9I2GWBxBRTTCz/rH+u/akBK0JhiHWzxF+BYYRly4g4eNWzTJHjtI8+Eelmr+hZI3i7dw zO7DLJA0j1QYyt2qdRo+pav4J0yY73kQCNQwu2dkLcq8dvc5bKVcARga5aYEVniBiN2B0dp56 xt/QkA+Tpxrmmtf7J66RuvvIBiBmkogjUVoYFilAjPYEWXqYjIFdQXpAXipsIvU23nGJBW+Sh dtUWmRk52oc1vRJjOnOl2bwqsujaU8IL0+0yQg== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: 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 Link: https://bugs.linaro.org/show_bug.cgi?id=3145 Signed-off-by: Arnd Bergmann --- tools/testing/selftests/vm/compaction_test.c | 2 ++ 1 file changed, 2 insertions(+) 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"); -- 2.9.0