This is a note to let you know that I've just added the patch titled

    NFS: Fix panic after nfs_umount()

to the 2.6.32-longterm tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/longterm/longterm-queue-2.6.32.git;a=summary

The filename of the patch is:
     nfs-fix-panic-after-nfs_umount.patch
and it can be found in the queue-2.6.32 subdirectory.

If you, or anyone else, feels it should not be added to the 2.6.32 longterm 
tree,
please let <[email protected]> know about it.


>From 5b362ac3799ff4225c40935500f520cad4d7ed66 Mon Sep 17 00:00:00 2001
From: Chuck Lever <[email protected]>
Date: Fri, 10 Dec 2010 12:31:14 -0500
Subject: NFS: Fix panic after nfs_umount()

From: Chuck Lever <[email protected]>

commit 5b362ac3799ff4225c40935500f520cad4d7ed66 upstream.

After a few unsuccessful NFS mount attempts in which the client and
server cannot agree on an authentication flavor both support, the
client panics.  nfs_umount() is invoked in the kernel in this case.

Turns out nfs_umount()'s UMNT RPC invocation causes the RPC client to
write off the end of the rpc_clnt's iostat array.  This is because the
mount client's nrprocs field is initialized with the count of defined
procedures (two: MNT and UMNT), rather than the size of the client's
proc array (four).

The fix is to use the same initialization technique used by most other
upper layer clients in the kernel.

Introduced by commit 0b524123, which failed to update nrprocs when
support was added for UMNT in the kernel.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=24302
BugLink: http://bugs.launchpad.net/bugs/683938

Reported-by: Stefan Bader <[email protected]>
Tested-by: Stefan Bader <[email protected]>
Signed-off-by: Chuck Lever <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 fs/nfs/mount_clnt.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/fs/nfs/mount_clnt.c
+++ b/fs/nfs/mount_clnt.c
@@ -503,13 +503,13 @@ static struct rpc_procinfo mnt3_procedur
 
 static struct rpc_version mnt_version1 = {
        .number         = 1,
-       .nrprocs        = 2,
+       .nrprocs        = ARRAY_SIZE(mnt_procedures),
        .procs          = mnt_procedures,
 };
 
 static struct rpc_version mnt_version3 = {
        .number         = 3,
-       .nrprocs        = 2,
+       .nrprocs        = ARRAY_SIZE(mnt3_procedures),
        .procs          = mnt3_procedures,
 };
 


Patches currently in longterm-queue-2.6.32 which might be from 
[email protected] are

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