Description of problem:

If we know that the delegation stateid is bad or revoked, we need to
remove that delegation as soon as possible, and then mark all the
stateids that relied on that delegation for recovery. We cannot use
the delegation as part of the recovery process.


Version-Release number of selected component (if applicable):


How reproducible:
100% with the ability for the admin to revoke a stateid on the NFSv4.0/v4.1 server


Steps to Reproduce:
1. Open a file with a delegation
2. Perform I/O - READ the file
3. During I/O revoke the delegation stated
  
Actual results:
A READ will return with NFS4ERR_BAD_STATEID. The client will start the recovery process, but it will not complete.  Either the client will hang, or the READ will be resent with the revoked stateid, and the application will see an input/output error.

Expected results:
With this patch, the (possibly a delegation) stateid is recovered via an OPEN with CLAIM_NULL, the READ is resent with the new stateid and all is well.

Additional info:

Here is the upstream patch queued for stable:

From a1d0b5eebc4fd6e0edb02688b35f17f67f42aea5 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <Trond.Myklebust>
Date: Mon, 5 Mar 2012 19:56:44 -0500
Subject: [PATCH] NFS: Properly handle the case where the delegation is
 revoked