diff --git a/block-raw-posix.c b/block-raw-posix.c
index b35c9d0..4874b8e 100644
--- a/block-raw-posix.c
+++ b/block-raw-posix.c
@@ -1374,7 +1374,7 @@
         unsigned long int req, void *buf,
         BlockDriverCompletionFunc *cb, void *opaque)
 {
-    return -ENOTSUP;
+    return NULL;
 }
 #endif /* !linux && !FreeBSD */