From patchwork Tue Oct 19 00:10:42 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guo-Fu Tseng X-Patchwork-Id: 68259 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 981141007D5 for ; Tue, 19 Oct 2010 11:21:15 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932154Ab0JSAVI (ORCPT ); Mon, 18 Oct 2010 20:21:08 -0400 Received: from cooldavid.org ([114.33.45.68]:49740 "EHLO cooldavid.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757434Ab0JSAU6 (ORCPT ); Mon, 18 Oct 2010 20:20:58 -0400 Received: from kh (kh.cooldavid.org [114.33.146.108]) by cooldavid.org (Postfix) with SMTP id 4CFD220B63C; Tue, 19 Oct 2010 08:35:21 +0800 (CST) Received: by kh (sSMTP sendmail emulation); Tue, 19 Oct 2010 08:11:16 +0800 From: "Guo-Fu Tseng" To: "David Miller" Cc: Guo-Fu Tseng , "linux-netdev" Subject: [PATCH net-next-2.6 3/5] jme: Prevent possible read re-order error Date: Tue, 19 Oct 2010 08:10:42 +0800 Message-Id: <1287447044-24471-3-git-send-email-cooldavid@cooldavid.org> X-Mailer: git-send-email 1.7.2.2 In-Reply-To: <1287447044-24471-1-git-send-email-cooldavid@cooldavid.org> References: <1287447044-24471-1-git-send-email-cooldavid@cooldavid.org> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Guo-Fu Tseng Adding read memory barrier in between flag reading and data reading of receive descriptors. This prevents the data being read before hardware complete writing informations. Reported-by: Stefan Hajnoczi Signed-off-by: Guo-Fu Tseng --- drivers/net/jme.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/drivers/net/jme.c b/drivers/net/jme.c index 0ea0da3..095f899 100644 --- a/drivers/net/jme.c +++ b/drivers/net/jme.c @@ -989,6 +989,7 @@ jme_process_receive(struct jme_adapter *jme, int limit) goto out; --limit; + rmb(); desccnt = rxdesc->descwb.desccnt & RXWBDCNT_DCNT; if (unlikely(desccnt > 1 ||