diff --git a/Documentation/filesystems/9p.txt b/Documentation/filesystems/9p.txt
index fec7144e817c41133de47caf83e19f322d7367b4..3fb780ffdf23a0bae9db60a9e278d924682b08e8 100644
--- a/Documentation/filesystems/9p.txt
+++ b/Documentation/filesystems/9p.txt
@@ -133,6 +133,16 @@ OPTIONS
 		cache tags for existing cache sessions can be listed at
 		/sys/fs/9p/caches. (applies only to cache=fscache)
 
+BEHAVIOR
+========
+
+This section aims at describing 9p 'quirks' that can be different
+from a local filesystem behaviors.
+
+ - Setting O_NONBLOCK on a file will make client reads return as early
+   as the server returns some data instead of trying to fill the read
+   buffer with the requested amount of bytes or end of file is reached.
+
 RESOURCES
 =========