From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936855AbdCXQsI (ORCPT ); Fri, 24 Mar 2017 12:48:08 -0400 Received: from resqmta-ch2-01v.sys.comcast.net ([69.252.207.33]:53216 "EHLO resqmta-ch2-01v.sys.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936840AbdCXQr7 (ORCPT ); Fri, 24 Mar 2017 12:47:59 -0400 Reply-To: shuah@kernel.org Subject: Re: [PATCH] selftests/vm: Set mmap()'s fd as -1 for MAP_ANONYMOUS flag References: <20170315131926.461-1-sj38.park@gmail.com> To: SeongJae Park , Andrew Morton Cc: Simon Guo , linux-kselftest@vger.kernel.org, "linux-kernel@vger.kernel.org" , Shuah Khan , Shuah Khan From: Shuah Khan Message-ID: <09a5192e-5a10-c314-4c20-55d57af40015@kernel.org> Date: Fri, 24 Mar 2017 10:47:55 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-CMAE-Envelope: MS4wfHaSYwQ3QNGsHtKrebLTZwQ/CnyA1G20gns0mdg+S8B16KpWglZ8Pmois25CdCs1VSd0py+TaE4M0m6MyQtLki2oaSzf2WV9kVjHz5k+N7OV+T/hIsqR hrdsJZTjPC9UKeKDBWiK1XMRMMRU/L7hE1tecTpcWEzALh4CVBcPMAPc2NDDxYckOntSi78lDyj8ne9GKcjNZR+6cPZqT813VDQvh4b7laXoWxigxZOEoBWb Z8tLkqZ5xXsVx2BCSb6d5RDattyVVnHDpVZ/MECgSIgxzJ2zbuqTQA4QsPsTHkUGFNro55W3QbE2pky7P+7YzjSFonLMmkoR2pb7AGM0TNJH86RmTx86EZ8g o41u5SRlNRJxarppc1QtFK27GGWB+SnY1fRr5F9/V+bk7vBUdIk= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/22/2017 07:09 PM, SeongJae Park wrote: > Hello Shuah, > > > May I ask some comments? > > > Thanks, > SeongJae Park > > On Wed, Mar 15, 2017 at 10:19 PM, SeongJae Park wrote: >> Man page of mmap() says that portable applications should ensure fd >> argument to be -1 if MAP_ANONYMOUS flag is set as below: >> ``` >> The mapping is not backed by any file; its contents are initialized to >> zero. The fd and offset arguments are ignored; however, some >> implementations require fd to be -1 if MAP_ANONYMOUS (or >> MAP_ANON) is specified, and portable applications >> should ensure this. >> ``` >> >> However, few mmap() calls under selftests/vm/ uses 0 as fd though they >> use MAP_ANONYMOUS flag. This commit changes the argument to be -1 as >> recommended. Hi Andrew, Do you have comments on this patch? Please Ack it if you would like me to take it thorugh ksefltest tree. thanks, -- Shuah >> >> Signed-off-by: SeongJae Park >> --- >> tools/testing/selftests/vm/map_hugetlb.c | 2 +- >> tools/testing/selftests/vm/mlock2-tests.c | 12 ++++++------ >> tools/testing/selftests/vm/on-fault-limit.c | 2 +- >> tools/testing/selftests/vm/thuge-gen.c | 2 +- >> 4 files changed, 9 insertions(+), 9 deletions(-) >> >> diff --git a/tools/testing/selftests/vm/map_hugetlb.c b/tools/testing/selftests/vm/map_hugetlb.c >> index addcd6fc1ecc..77687ab59f77 100644 >> --- a/tools/testing/selftests/vm/map_hugetlb.c >> +++ b/tools/testing/selftests/vm/map_hugetlb.c >> @@ -62,7 +62,7 @@ int main(void) >> void *addr; >> int ret; >> >> - addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, 0, 0); >> + addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, -1, 0); >> if (addr == MAP_FAILED) { >> perror("mmap"); >> exit(1); >> diff --git a/tools/testing/selftests/vm/mlock2-tests.c b/tools/testing/selftests/vm/mlock2-tests.c >> index ff0cda2b19c9..e5dbc87b4297 100644 >> --- a/tools/testing/selftests/vm/mlock2-tests.c >> +++ b/tools/testing/selftests/vm/mlock2-tests.c >> @@ -293,7 +293,7 @@ static int test_mlock_lock() >> unsigned long page_size = getpagesize(); >> >> map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE, >> - MAP_ANONYMOUS | MAP_PRIVATE, 0, 0); >> + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); >> if (map == MAP_FAILED) { >> perror("test_mlock_locked mmap"); >> goto out; >> @@ -402,7 +402,7 @@ static int test_mlock_onfault() >> unsigned long page_size = getpagesize(); >> >> map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE, >> - MAP_ANONYMOUS | MAP_PRIVATE, 0, 0); >> + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); >> if (map == MAP_FAILED) { >> perror("test_mlock_locked mmap"); >> goto out; >> @@ -445,7 +445,7 @@ static int test_lock_onfault_of_present() >> uint64_t page1_flags, page2_flags; >> >> map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE, >> - MAP_ANONYMOUS | MAP_PRIVATE, 0, 0); >> + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); >> if (map == MAP_FAILED) { >> perror("test_mlock_locked mmap"); >> goto out; >> @@ -492,7 +492,7 @@ static int test_munlockall() >> unsigned long page_size = getpagesize(); >> >> map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE, >> - MAP_ANONYMOUS | MAP_PRIVATE, 0, 0); >> + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); >> >> if (map == MAP_FAILED) { >> perror("test_munlockall mmap"); >> @@ -518,7 +518,7 @@ static int test_munlockall() >> munmap(map, 2 * page_size); >> >> map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE, >> - MAP_ANONYMOUS | MAP_PRIVATE, 0, 0); >> + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); >> >> if (map == MAP_FAILED) { >> perror("test_munlockall second mmap"); >> @@ -573,7 +573,7 @@ static int test_vma_management(bool call_mlock) >> struct vm_boundaries page3; >> >> map = mmap(NULL, 3 * page_size, PROT_READ | PROT_WRITE, >> - MAP_ANONYMOUS | MAP_PRIVATE, 0, 0); >> + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); >> if (map == MAP_FAILED) { >> perror("mmap()"); >> return ret; >> diff --git a/tools/testing/selftests/vm/on-fault-limit.c b/tools/testing/selftests/vm/on-fault-limit.c >> index 0ae458f32fdb..7f96a5c2e292 100644 >> --- a/tools/testing/selftests/vm/on-fault-limit.c >> +++ b/tools/testing/selftests/vm/on-fault-limit.c >> @@ -26,7 +26,7 @@ static int test_limit(void) >> } >> >> map = mmap(NULL, 2 * lims.rlim_max, PROT_READ | PROT_WRITE, >> - MAP_PRIVATE | MAP_ANONYMOUS | MAP_POPULATE, 0, 0); >> + MAP_PRIVATE | MAP_ANONYMOUS | MAP_POPULATE, -1, 0); >> if (map != MAP_FAILED) >> printf("mmap should have failed, but didn't\n"); >> else { >> diff --git a/tools/testing/selftests/vm/thuge-gen.c b/tools/testing/selftests/vm/thuge-gen.c >> index 0bc737a75150..88a2ab535e01 100644 >> --- a/tools/testing/selftests/vm/thuge-gen.c >> +++ b/tools/testing/selftests/vm/thuge-gen.c >> @@ -146,7 +146,7 @@ void test_mmap(unsigned long size, unsigned flags) >> >> before = read_free(size); >> map = mmap(NULL, size*NUM_PAGES, PROT_READ|PROT_WRITE, >> - MAP_PRIVATE|MAP_ANONYMOUS|MAP_HUGETLB|flags, 0, 0); >> + MAP_PRIVATE|MAP_ANONYMOUS|MAP_HUGETLB|flags, -1, 0); >> >> if (map == (char *)-1) err("mmap"); >> memset(map, 0xff, size*NUM_PAGES); >> -- >> 2.10.0 >> > >