[for-next][PATCH 1/2] selftests/ring-buffer: Verify the entire meta-page padding

From: Steven Rostedt
Date: Wed Sep 11 2024 - 12:28:01 EST


From: Vincent Donnefort <vdonnefort@xxxxxxxxxx>

Improve the ring-buffer meta-page test coverage by checking for the
entire padding region to be 0 instead of just looking at the first 4
bytes.

Cc: linux-kselftest@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/20240910162335.2993310-2-vdonnefort@xxxxxxxxxx
Acked-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Vincent Donnefort <vdonnefort@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
tools/testing/selftests/ring-buffer/map_test.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/ring-buffer/map_test.c b/tools/testing/selftests/ring-buffer/map_test.c
index 4bb0192e43f3..ba12fd31de87 100644
--- a/tools/testing/selftests/ring-buffer/map_test.c
+++ b/tools/testing/selftests/ring-buffer/map_test.c
@@ -231,15 +231,15 @@ TEST_F(map, data_mmap)

/* Verify meta-page padding */
if (desc->meta->meta_page_size > getpagesize()) {
- void *addr;
-
data_len = desc->meta->meta_page_size;
data = mmap(NULL, data_len,
PROT_READ, MAP_SHARED, desc->cpu_fd, 0);
ASSERT_NE(data, MAP_FAILED);

- addr = (void *)((unsigned long)data + getpagesize());
- ASSERT_EQ(*((int *)addr), 0);
+ for (int i = desc->meta->meta_struct_len;
+ i < desc->meta->meta_page_size; i += sizeof(int))
+ ASSERT_EQ(*(int *)(data + i), 0);
+
munmap(data, data_len);
}
}
--
2.45.2