diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c
index 8a09057d2f22..9354a5e0321c 100644
--- a/tools/testing/selftests/vm/userfaultfd.c
+++ b/tools/testing/selftests/vm/userfaultfd.c
@@ -87,7 +87,7 @@ static bool test_uffdio_minor = false;
 
 static bool map_shared;
 static int shm_fd;
-static int huge_fd;
+static int huge_fd = -1;	/* only used for hugetlb_shared test */
 static char *huge_fd_off0;
 static unsigned long long *count_verify;
 static int uffd = -1;
@@ -223,6 +223,9 @@ static void noop_alias_mapping(__u64 *start, size_t len, unsigned long offset)
 
 static void hugetlb_release_pages(char *rel_area)
 {
+	if (huge_fd == -1)
+		return;
+
 	if (fallocate(huge_fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
 		      rel_area == huge_fd_off0 ? 0 : nr_pages * page_size,
 		      nr_pages * page_size))
@@ -235,16 +238,17 @@ static void hugetlb_allocate_area(void **alloc_area)
 	char **alloc_area_alias;
 
 	*alloc_area = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE,
-			   (map_shared ? MAP_SHARED : MAP_PRIVATE) |
-			   MAP_HUGETLB,
-			   huge_fd, *alloc_area == area_src ? 0 :
-			   nr_pages * page_size);
+			   map_shared ? MAP_SHARED :
+			   MAP_PRIVATE | MAP_HUGETLB |
+			   (*alloc_area == area_src ? 0 : MAP_NORESERVE),
+			   huge_fd,
+			   *alloc_area == area_src ? 0 : nr_pages * page_size);
 	if (*alloc_area == MAP_FAILED)
 		err("mmap of hugetlbfs file failed");
 
 	if (map_shared) {
 		area_alias = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE,
-				  MAP_SHARED | MAP_HUGETLB,
+				  MAP_SHARED,
 				  huge_fd, *alloc_area == area_src ? 0 :
 				  nr_pages * page_size);
 		if (area_alias == MAP_FAILED)