diff options
author | David Rientjes <rientjes@google.com> | 2015-04-15 23:14:29 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-15 23:35:19 (GMT) |
commit | 215ba78115f82ad5f8faedac98cc42e572733b8a (patch) | |
tree | a3fba3474be13c9f9002118f4bb81b6e15e18c3c | |
parent | 80d6b94bd69a7a49b52bf503ef6a841f43cf5bbb (diff) | |
download | linux-215ba78115f82ad5f8faedac98cc42e572733b8a.tar.xz |
mm, selftests: test return value of munmap for MAP_HUGETLB memory
When MAP_HUGETLB memory is unmapped, the length must be hugepage aligned,
otherwise it fails with -EINVAL.
All tests currently behave correctly, but it's better to explcitly test
the return value for completeness and document the requirement, especially
if users copy map_hugetlb.c as a sample implementation.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Joern Engel <joern@logfs.org>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: Eric B Munson <emunson@akamai.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | tools/testing/selftests/powerpc/mm/hugetlb_vs_thp_test.c | 8 | ||||
-rw-r--r-- | tools/testing/selftests/vm/hugetlbfstest.c | 4 | ||||
-rw-r--r-- | tools/testing/selftests/vm/map_hugetlb.c | 6 |
3 files changed, 14 insertions, 4 deletions
diff --git a/tools/testing/selftests/powerpc/mm/hugetlb_vs_thp_test.c b/tools/testing/selftests/powerpc/mm/hugetlb_vs_thp_test.c index 3d8e5b0..4900367 100644 --- a/tools/testing/selftests/powerpc/mm/hugetlb_vs_thp_test.c +++ b/tools/testing/selftests/powerpc/mm/hugetlb_vs_thp_test.c @@ -21,9 +21,13 @@ static int test_body(void) * Typically the mmap will fail because no huge pages are * allocated on the system. But if there are huge pages * allocated the mmap will succeed. That's fine too, we just - * munmap here before continuing. + * munmap here before continuing. munmap() length of + * MAP_HUGETLB memory must be hugepage aligned. */ - munmap(addr, SIZE); + if (munmap(addr, SIZE)) { + perror("munmap"); + return 1; + } } p = mmap(addr, SIZE, PROT_READ | PROT_WRITE, diff --git a/tools/testing/selftests/vm/hugetlbfstest.c b/tools/testing/selftests/vm/hugetlbfstest.c index ea40ff8..02e1072 100644 --- a/tools/testing/selftests/vm/hugetlbfstest.c +++ b/tools/testing/selftests/vm/hugetlbfstest.c @@ -34,6 +34,7 @@ static void do_mmap(int fd, int extra_flags, int unmap) int *p; int flags = MAP_PRIVATE | MAP_POPULATE | extra_flags; u64 before, after; + int ret; before = read_rss(); p = mmap(NULL, length, PROT_READ | PROT_WRITE, flags, fd, 0); @@ -44,7 +45,8 @@ static void do_mmap(int fd, int extra_flags, int unmap) !"rss didn't grow as expected"); if (!unmap) return; - munmap(p, length); + ret = munmap(p, length); + assert(!ret || !"munmap returned an unexpected error"); after = read_rss(); assert(llabs(after - before) < 0x40000 || !"rss didn't shrink as expected"); diff --git a/tools/testing/selftests/vm/map_hugetlb.c b/tools/testing/selftests/vm/map_hugetlb.c index ac56639..addcd6f 100644 --- a/tools/testing/selftests/vm/map_hugetlb.c +++ b/tools/testing/selftests/vm/map_hugetlb.c @@ -73,7 +73,11 @@ int main(void) write_bytes(addr); ret = read_bytes(addr); - munmap(addr, LENGTH); + /* munmap() length of MAP_HUGETLB memory must be hugepage aligned */ + if (munmap(addr, LENGTH)) { + perror("munmap"); + exit(1); + } return ret; } |