[LTP] [PATCH] syscalls/madvise02.c: Fix ENOMEM errno tests

[LTP] [PATCH] syscalls/madvise02.c: Fix ENOMEM errno tests

[Xiao Yang]

With commit 212a4b9 on some distros(e.g. RHEL6.9/7.5), running
madvise02 got the following error:
------------------------------------------------------
...
madvise02.c:181: CONF: MADV_UNMERGEABLE is not supported
madvise02.c:196: FAIL: madvise succeeded unexpectedly
madvise02.c:196: FAIL: madvise succeeded unexpectedly
madvise02.c:181: CONF: MADV_WILLNEED is not supported
...
-------------------------------------------------------

If MAP_SIZE was equal to a pagesize, shared_anon may get the same
address which was a part of file2 and already unmapped, so that the
whole address of file2 became valid again.  Subsequently, ENOMEM
errno tests succeeded, so changing the order of mmaps to make
shared_anon get different address.

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
---
 testcases/kernel/syscalls/madvise/madvise02.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/testcases/kernel/syscalls/madvise/madvise02.c b/testcases/kernel/syscalls/madvise/madvise02.c
index 53e4f51..f683a99 100644
--- a/testcases/kernel/syscalls/madvise/madvise02.c
+++ b/testcases/kernel/syscalls/madvise/madvise02.c
@@ -156,11 +156,11 @@ static void setup(void)
 	SAFE_FSTAT(fd, &st);
 
 	file1 = SAFE_MMAP(0, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
+	shared_anon = SAFE_MMAP(0, MAP_SIZE, PROT_READ, MAP_SHARED |
+			 MAP_ANONYMOUS, -1, 0);
 	file2 = SAFE_MMAP(0, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
 	SAFE_MUNMAP(file2 + st.st_size - pagesize, pagesize);
 	file3 = SAFE_MMAP(0, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
-	shared_anon = SAFE_MMAP(0, MAP_SIZE, PROT_READ, MAP_SHARED |
-			MAP_ANONYMOUS, -1, 0);
 
 	nonalign = file1 + 100;
 
-- 
1.8.3.1

[LTP] [PATCH] syscalls/madvise02.c: Fix ENOMEM errno tests

[Jan Stancek]

----- Original Message -----
> With commit 212a4b9 on some distros(e.g. RHEL6.9/7.5), running
> madvise02 got the following error:
> ------------------------------------------------------
> ...
> madvise02.c:181: CONF: MADV_UNMERGEABLE is not supported
> madvise02.c:196: FAIL: madvise succeeded unexpectedly
> madvise02.c:196: FAIL: madvise succeeded unexpectedly
> madvise02.c:181: CONF: MADV_WILLNEED is not supported
> ...
> -------------------------------------------------------
> 
> If MAP_SIZE was equal to a pagesize, shared_anon may get the same
> address which was a part of file2 and already unmapped, so that the
> whole address of file2 became valid again.  Subsequently, ENOMEM
> errno tests succeeded, so changing the order of mmaps to make
> shared_anon get different address.
> 
> Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>

Hi,

I changed patch to move MUNMAP() instead and added comment
explaining why.

You can review it here:
  https://github.com/linux-test-project/ltp/commit/030e321ce1dfdc3a8daf7ef5a5b7bb7734cf2d9f

Thanks,
Jan

[LTP] [PATCH] syscalls/madvise02.c: Fix ENOMEM errno tests

[Xiao Yang]

On 2018/07/26 15:46, Jan Stancek wrote:
> ----- Original Message -----
>> With commit 212a4b9 on some distros(e.g. RHEL6.9/7.5), running
>> madvise02 got the following error:
>> ------------------------------------------------------
>> ...
>> madvise02.c:181: CONF: MADV_UNMERGEABLE is not supported
>> madvise02.c:196: FAIL: madvise succeeded unexpectedly
>> madvise02.c:196: FAIL: madvise succeeded unexpectedly
>> madvise02.c:181: CONF: MADV_WILLNEED is not supported
>> ...
>> -------------------------------------------------------
>>
>> If MAP_SIZE was equal to a pagesize, shared_anon may get the same
>> address which was a part of file2 and already unmapped, so that the
>> whole address of file2 became valid again.  Subsequently, ENOMEM
>> errno tests succeeded, so changing the order of mmaps to make
>> shared_anon get different address.
>>
>> Signed-off-by: Xiao Yang<yangx.jy@cn.fujitsu.com>
> Hi,
>
> I changed patch to move MUNMAP() instead and added comment
> explaining why.
>
> You can review it here:
>    https://github.com/linux-test-project/ltp/commit/030e321ce1dfdc3a8daf7ef5a5b7bb7734cf2d9f
Hi Jan,

Thanks for your quick review, and it seems better to me. :-)

Thanks,
Xiao Yang
> Thanks,
> Jan
>
>
>