From 71cd1dd4b91859128b87967bab32f4cf48d475b9 Mon Sep 17 00:00:00 2001
From: David van Moolenbroek <david@minix3.org>
Date: Sun, 24 Aug 2014 09:26:17 +0000
Subject: [PATCH] VFS: do not call REQ_FLUSH on the root file system

Change-Id: I15d29a6f3d198e604ea7f7a9db600d6d18b6994b
---
 minix/servers/vfs/filedes.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/minix/servers/vfs/filedes.c b/minix/servers/vfs/filedes.c
index 6adc70386..13bd6c8b6 100644
--- a/minix/servers/vfs/filedes.c
+++ b/minix/servers/vfs/filedes.c
@@ -365,12 +365,12 @@ struct filp *f;
 		dev = vp->v_sdev;
 		if (S_ISBLK(vp->v_mode))  {
 			lock_bsf();
-			if (vp->v_bfs_e == ROOT_FS_E) {
+			if (vp->v_bfs_e == ROOT_FS_E && dev != ROOT_DEV) {
 				/* Invalidate the cache unless the special is
-				 * mounted. Assume that the root filesystem's
-				 * is open only for fsck.
+				 * mounted. Be careful not to flush the root
+				 * file system either.
 				 */
-				req_flush(vp->v_bfs_e, dev);
+				(void) req_flush(vp->v_bfs_e, dev);
 			}
 			unlock_bsf();