From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755082Ab1CUX6C (ORCPT ); Mon, 21 Mar 2011 19:58:02 -0400 Received: from kroah.org ([198.145.64.141]:49076 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755079Ab1CUXN7 (ORCPT ); Mon, 21 Mar 2011 19:13:59 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Mon Mar 21 16:10:53 2011 Message-Id: <20110321231053.558701745@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Mon, 21 Mar 2011 16:10:08 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Trond Myklebust Subject: [28/44] SUNRPC: Ensure we always run the tk_callback before tk_action In-Reply-To: <20110321231105.GA1744@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm 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);