tests: make tail_alloc create additional memory mapping holes

* tests/tail_alloc.c (tail_alloc): Create additional memory mapping
holes before and after the allocated memory.

diff --git a/tests/tail_alloc.c b/tests/tail_alloc.c
index 82e1aacb1fd10844ab9f03756be8b65fe17358d3..08081d4fc07c5f8467e7c0eccc0d0220b6a43cc6 100644 (file)
--- a/tests/tail_alloc.c
+++ b/tests/tail_alloc.c
@@ -34,17 +34,20 @@ tail_alloc(const size_t size)
 {
        const size_t page_size = get_page_size();
        const size_t len = (size + page_size - 1) & -page_size;
-       const size_t alloc_size = len + 2 * page_size;
+       const size_t alloc_size = len + 6 * page_size;
 
        void *p = mmap(NULL, alloc_size, PROT_READ | PROT_WRITE,
                       MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
        if (MAP_FAILED == p)
                perror_msg_and_fail("mmap(%zu)", alloc_size);
 
-       void *start_work = p + page_size;
+       void *start_work = p + 3 * page_size;
        void *tail_guard = start_work + len;
 
-       if (munmap(p, page_size) || munmap(tail_guard, page_size))
+       if (munmap(p, page_size) ||
+           munmap(p + 2 * page_size, page_size) ||
+           munmap(tail_guard, page_size) ||
+           munmap(tail_guard + 2 * page_size, page_size))
                perror_msg_and_fail("munmap");
 
        memset(start_work, 0xff, len);