sunrpc: fix loss of task->tk_status after rpc_delay call in xprt_alloc_slot

xprt_alloc_slot will call rpc_delay() to make the task wait a bit before
retrying when it gets back an -ENOMEM error from xprt_dynamic_alloc_slot.
The problem is that rpc_delay will clear the task->tk_status, causing
call_reserveresult to abort the task.

The solution is simply to let call_reserveresult handle the ENOMEM error
directly.

Reported-by: Jeff Layton <jlayton@redhat.com>
Cc: stable@vger.kernel.org [>= 3.1]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

2 files changed, 5 insertions, 2 deletions

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index adf2990acebf..25302c802460 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -1288,6 +1288,8 @@ call_reserveresult(struct rpc_task *task)
         }
 
         switch (status) {
+        case -ENOMEM:
+                rpc_delay(task, HZ >> 2);
         case -EAGAIN:   /* woken up; retry */
                 task->tk_action = call_reserve;
                 return;
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index b239e75c483f..d7ccd7923eab 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -984,15 +984,16 @@ static void xprt_alloc_slot(struct rpc_task *task)
                 goto out_init_req;
         switch (PTR_ERR(req)) {
         case -ENOMEM:
-                rpc_delay(task, HZ >> 2);
                 dprintk("RPC:       dynamic allocation of request slot "
                                 "failed! Retrying\n");
+                task->tk_status = -ENOMEM;
                 break;
         case -EAGAIN:
                 rpc_sleep_on(&xprt->backlog, task, NULL);
                 dprintk("RPC:       waiting for request slot\n");
+        default:
+                task->tk_status = -EAGAIN;
         }
-        task->tk_status = -EAGAIN;
         return;
 out_init_req:
         task->tk_status = 0;