2.6.35-longterm review patch.  If anyone has any objections, please let me know.

------------------
From: Konstantin Khorenko <[email protected]>

commit 3aa6e0aa8ab3e64bbfba092c64d42fd1d006b124 upstream.

If nfsd fails to find an exported via NFS file in the readahead cache, it
should increment corresponding nfsdstats counter (ra_depth[10]), but due to a
bug it may instead write to ra_depth[11], corrupting the following field.

In a kernel with NFSDv4 compiled in the corruption takes the form of an
increment of a counter of the number of NFSv4 operation 0's received; since
there is no operation 0, this is harmless.

In a kernel with NFSDv4 disabled it corrupts whatever happens to be in the
memory beyond nfsdstats.

Signed-off-by: Konstantin Khorenko <[email protected]>
Signed-off-by: J. Bruce Fields <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Andi Kleen <[email protected]>

---
 fs/nfsd/vfs.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6.35.y/fs/nfsd/vfs.c
===================================================================
--- linux-2.6.35.y.orig/fs/nfsd/vfs.c   2011-03-29 22:51:24.834087726 -0700
+++ linux-2.6.35.y/fs/nfsd/vfs.c        2011-03-29 23:03:00.482287829 -0700
@@ -819,7 +819,7 @@
                if (ra->p_count == 0)
                        frap = rap;
        }
-       depth = nfsdstats.ra_size*11/10;
+       depth = nfsdstats.ra_size;
        if (!frap) {    
                spin_unlock(&rab->pb_lock);
                return NULL;

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