NLM: Don't hang forever on NLM unlock requests

If the NLM daemon is killed on the NFS server, we can currently end up
hanging forever on an 'unlock' request, instead of aborting. Basically,
if the rpcbind request fails, or the server keeps returning garbage, we
really want to quit instead of retrying.

Tested-by: Vasily Averin <vvs@sw.ru>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

1 files changed, 7 insertions, 1 deletions

diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c
index adb45ec9038c..e374050a911c 100644
--- a/fs/lockd/clntproc.c
+++ b/fs/lockd/clntproc.c
@@ -708,7 +708,13 @@ static void nlmclnt_unlock_callback(struct rpc_task *task, void *data)
 
         if (task->tk_status < 0) {
                 dprintk("lockd: unlock failed (err = %d)\n", -task->tk_status);
-                goto retry_rebind;
+                switch (task->tk_status) {
+                case -EACCES:
+                case -EIO:
+                        goto die;
+                default:
+                        goto retry_rebind;
+                }
         }
         if (status == NLM_LCK_DENIED_GRACE_PERIOD) {
                 rpc_delay(task, NLMCLNT_GRACE_WAIT);