[PATCH 1/1] fix d_revalidate oopsen on NFS exports

can't blindly check nd->flags in ->d_revalidate()

Has been previously done for various other file systems:

git blame -L 1768,+1 fs/proc/base.c
34286d66 (Nick Piggin 2011-01-07 17:49:57 +1100 1768) 	if (nd && nd->flags & LOOKUP_RCU)
git blame -L 645,+1 fs/cifs/dir.c
3ca30d40 (Pavel Shilovsky 2011-07-25 17:59:10 +0400 645) 	if (nd && (nd->flags & LOOKUP_RCU))
git blame -L 46,+1 fs/fat/namei_vfat.c
9177ada9 (Al Viro 2011-03-10 03:45:49 -0500 46) 	if (nd && nd->flags & LOOKUP_RCU)
git blame -L 57,+1 fs/fat/namei_vfat.c
9177ada9 (Al Viro 2011-03-10 03:45:49 -0500 57) 	if (nd && nd->flags & LOOKUP_RCU)
git blame -L 177,+1 fs/fuse/dir.c
d2433905 (Miklos Szeredi 2011-05-10 17:35:58 +0200 177) 		if (nd && (nd->flags & LOOKUP_RCU))
git blame -L 1036,+1 fs/ceph/dir.c
0eb980e3 (Al Viro 2011-03-10 03:44:05 -0500 1036) 	if (nd && nd->flags & LOOKUP_RCU)
git blame -L 47,+1 fs/gfs2/dentry.c
53fe9241 (Al Viro 2011-03-10 03:44:48 -0500 47) 	if (nd && nd->flags & LOOKUP_RCU)
git blame -L 53,+1 fs/ecryptfs/dentry.c
70b89021 (Tyler Hicks 2011-02-17 17:35:20 -0600 53) 	if (nd && nd->flags & LOOKUP_RCU)
git blame -L 59,+1 fs/ocfs2/dcache.c
4714e637 (Al Viro 2011-03-10 03:45:07 -0500 59) 	if (nd && nd->flags & LOOKUP_RCU)

Signed-off-by: Chris Dunlop <chris <at> onthe.net.au>
---
 fs/9p/vfs_dentry.c    |    2 +-
 fs/afs/dir.c          |    2 +-
 fs/coda/dir.c         |    2 +-
 fs/hfs/sysdep.c       |    2 +-
 fs/jfs/namei.c        |    3 +++