NFSv4: Don't call put_rpccred() under the rcu_read_lock()

put_rpccred() can sleep.

Fixes: 8f649c3762547 ("NFSv4: Fix the locking in nfs_inode_reclaim_delegation()")
Cc: stable@vger.kernel.org # 2.6.35+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

fs/nfs/delegation.c

@@ -181,8 +181,8 @@ void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred,
 			clear_bit(NFS_DELEGATION_NEED_RECLAIM,
 				  &delegation->flags);
 			spin_unlock(&delegation->lock);
-			put_rpccred(oldcred);
 			rcu_read_unlock();
+			put_rpccred(oldcred);
 			trace_nfs4_reclaim_delegation(inode, res->delegation_type);
 		} else {
 			/* We appear to have raced with a delegation return. */