From 8670684a2f6afad862891d3ed53a882eb93d65ad Mon Sep 17 00:00:00 2001
From: Poul-Henning Kamp <phk@FreeBSD.org>
Date: Tue, 6 May 1997 15:19:38 +0000
Subject: [PATCH] Fix a race condition that did, after all, exist.

Reviewed by:	phk
Submitted by:	dfr
---
 sys/kern/vfs_export.c | 8 +++++---
 sys/kern/vfs_subr.c   | 8 +++++---
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/sys/kern/vfs_export.c b/sys/kern/vfs_export.c
index 295c233990ef..353c8672ee5d 100644
--- a/sys/kern/vfs_export.c
+++ b/sys/kern/vfs_export.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vfs_subr.c	8.31 (Berkeley) 5/26/95
- * $Id: vfs_subr.c,v 1.84 1997/04/30 03:09:15 dyson Exp $
+ * $Id: vfs_subr.c,v 1.85 1997/05/04 09:17:29 phk Exp $
  */
 
 /*
@@ -2149,8 +2149,10 @@ vtouch(vp)
 		return;
 	}
 	if (simple_lock_try(&vnode_free_list_slock)) {
-		TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
-		TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
+		if (vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb) {
+			TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
+			TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
+		}
 		simple_unlock(&vnode_free_list_slock);
 	}
 	simple_unlock(&vp->v_interlock);
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
index 295c233990ef..353c8672ee5d 100644
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vfs_subr.c	8.31 (Berkeley) 5/26/95
- * $Id: vfs_subr.c,v 1.84 1997/04/30 03:09:15 dyson Exp $
+ * $Id: vfs_subr.c,v 1.85 1997/05/04 09:17:29 phk Exp $
  */
 
 /*
@@ -2149,8 +2149,10 @@ vtouch(vp)
 		return;
 	}
 	if (simple_lock_try(&vnode_free_list_slock)) {
-		TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
-		TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
+		if (vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb) {
+			TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
+			TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
+		}
 		simple_unlock(&vnode_free_list_slock);
 	}
 	simple_unlock(&vp->v_interlock);