diff --git a/src/aio-dio-regress/aio-dio-append-write-fallocate-race.c b/src/aio-dio-regress/aio-dio-append-write-fallocate-race.c
index 091b047d..d3a2e5fc 100644
--- a/src/aio-dio-regress/aio-dio-append-write-fallocate-race.c
+++ b/src/aio-dio-regress/aio-dio-append-write-fallocate-race.c
@@ -65,7 +65,7 @@ test(
 	}
 	blocksize = sbuf.st_blksize;
 
-	ret = posix_memalign((void **)&buf, blocksize, blocksize);
+	ret = posix_memalign((void **)&buf, sysconf(_SC_PAGESIZE), blocksize);
 	if (ret) {
 		errno = ret;
 		perror("buffer");