From: Christoph Hellwig <hch@lst.de>
Date: Wed, 16 Oct 2013 19:48:53 +0000 (-0400)
Subject: exportfs: BUG_ON in crazy corner case
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=854ff5caabb5974b7464b438aba0bc47f1b6cf34;p=openwrt%2Fstaging%2Fblogic.git

exportfs: BUG_ON in crazy corner case

This would indicate a nasty bug in the dcache and has never triggered in
the past 10 years as far as I know.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c
index c43fe9b39ff2..6d0a7fa9abb3 100644
--- a/fs/exportfs/expfs.c
+++ b/fs/exportfs/expfs.c
@@ -112,18 +112,14 @@ reconnect_path(struct vfsmount *mnt, struct dentry *target_dir, char *nbuf)
 	while (target_dir->d_flags & DCACHE_DISCONNECTED && noprogress++ < 10) {
 		struct dentry *pd = find_disconnected_root(target_dir);
 
+		BUG_ON(pd == mnt->mnt_sb->s_root);
+
 		if (!IS_ROOT(pd)) {
 			/* must have found a connected parent - great */
 			spin_lock(&pd->d_lock);
 			pd->d_flags &= ~DCACHE_DISCONNECTED;
 			spin_unlock(&pd->d_lock);
 			noprogress = 0;
-		} else if (pd == mnt->mnt_sb->s_root) {
-			printk(KERN_ERR "export: Eeek filesystem root is not connected, impossible\n");
-			spin_lock(&pd->d_lock);
-			pd->d_flags &= ~DCACHE_DISCONNECTED;
-			spin_unlock(&pd->d_lock);
-			noprogress = 0;
 		} else {
 			/*
 			 * We have hit the top of a disconnected path, try to