From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932888Ab1DYUtc (ORCPT ); Mon, 25 Apr 2011 16:49:32 -0400 Received: from 1wt.eu ([62.212.114.60]:34165 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932223Ab1DYUYc (ORCPT ); Mon, 25 Apr 2011 16:24:32 -0400 Message-Id: <20110425200237.079370858@pcw.home.local> User-Agent: quilt/0.48-1 Date: Mon, 25 Apr 2011 22:04:06 +0200 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@kernel.org, stable-review@kernel.org Cc: Trond Myklebust , Greg Kroah-Hartman Subject: [PATCH 094/173] SUNRPC: Ensure we always run the tk_callback before tk_action In-Reply-To: <46075c3a3ef08be6d70339617d6afc98@local> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27.59-stable review patch. If anyone has any objections, please let us know. ------------------ From: Trond Myklebust commit e020c6800c9621a77223bf2c1ff68180e41e8ebf upstream. This fixes a race in which the task->tk_callback() puts the rpc_task to sleep, setting a new callback. Under certain circumstances, the current code may end up executing the task->tk_action before it gets round to the callback. Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman --- net/sunrpc/sched.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) --- a/net/sunrpc/sched.c +++ b/net/sunrpc/sched.c @@ -627,14 +627,12 @@ static void __rpc_execute(struct rpc_tas save_callback = task->tk_callback; task->tk_callback = NULL; save_callback(task); - } - - /* - * Perform the next FSM step. - * tk_action may be NULL when the task has been killed - * by someone else. - */ - if (!RPC_IS_QUEUED(task)) { + } else { + /* + * Perform the next FSM step. + * tk_action may be NULL when the task has been killed + * by someone else. + */ if (task->tk_action == NULL) break; task->tk_action(task);