Index: uspace/srv/vfs/vfs_lookup.c
===================================================================
--- uspace/srv/vfs/vfs_lookup.c	(revision d0a1d9614496f005605a8782410ffeb10da5ef29)
+++ uspace/srv/vfs/vfs_lookup.c	(revision 34356b2dd55bd8b155dde6fd600f45631a414ccb)
@@ -164,9 +164,10 @@
 	    &answer);
 	vfs_release_phone(phone);
-
+	
+	async_serialize_start();
 	ipcarg_t rc;
-	/* XXX shouldn't we disable fibril preemption here? */
 	async_wait_for(req, &rc);
-
+	async_serialize_end();
+	
 	futex_down(&plb_futex);
 	list_remove(&entry.plb_link);
Index: uspace/srv/vfs/vfs_ops.c
===================================================================
--- uspace/srv/vfs/vfs_ops.c	(revision d0a1d9614496f005605a8782410ffeb10da5ef29)
+++ uspace/srv/vfs/vfs_ops.c	(revision 34356b2dd55bd8b155dde6fd600f45631a414ccb)
@@ -487,9 +487,6 @@
 void vfs_open(ipc_callid_t rid, ipc_call_t *request)
 {
-	async_serialize_start();
-	
 	if (!vfs_files_init()) {
 		ipc_answer_0(rid, ENOMEM);
-		async_serialize_end();
 		return;
 	}
@@ -515,5 +512,4 @@
 	    (lflag & (L_FILE | L_DIRECTORY)) == (L_FILE | L_DIRECTORY)) {
 		ipc_answer_0(rid, EINVAL);
-		async_serialize_end();
 		return;
 	}
@@ -529,5 +525,4 @@
 		ipc_answer_0(callid, EINVAL);
 		ipc_answer_0(rid, EINVAL);
-		async_serialize_end();
 		return;
 	}
@@ -536,5 +531,4 @@
 		ipc_answer_0(callid, ENOMEM);
 		ipc_answer_0(rid, ENOMEM);
-		async_serialize_end();
 		return;
 	}
@@ -543,5 +537,4 @@
 		ipc_answer_0(rid, rc);
 		free(path);
-		async_serialize_end();
 		return;
 	}
@@ -568,5 +561,4 @@
 		ipc_answer_0(rid, rc);
 		free(path);
-		async_serialize_end();
 		return;
 	}
@@ -591,5 +583,4 @@
 				vfs_node_put(node);
 				ipc_answer_0(rid, rc);
-				async_serialize_end();
 				return;
 			}
@@ -607,5 +598,4 @@
 		vfs_node_put(node);
 		ipc_answer_0(rid, fd);
-		async_serialize_end();
 		return;
 	}
@@ -627,5 +617,4 @@
 	/* Success! Return the new file descriptor to the client. */
 	ipc_answer_1(rid, EOK, fd);
-	async_serialize_end();
 }