From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754104Ab1G0O2e (ORCPT ); Wed, 27 Jul 2011 10:28:34 -0400 Received: from moutng.kundenserver.de ([212.227.126.171]:53465 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753836Ab1G0O2c (ORCPT ); Wed, 27 Jul 2011 10:28:32 -0400 From: Arnd Bergmann To: Will Newton Subject: Re: [PATCH] bitops: Use volatile in generic atomic bitops. Date: Wed, 27 Jul 2011 16:28:29 +0200 User-Agent: KMail/1.12.2 (Linux/2.6.37; KDE/4.3.2; x86_64; ; ) Cc: Linux Kernel list , stable@kernel.org References: <201107271455.39511.arnd@arndb.de> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201107271628.29532.arnd@arndb.de> X-Provags-ID: V02:K0:7s0xUiPFahP/u1NVkFcUsMllm0ZcvCLK8gviKOwqkAT kXgPICdkra9CzHScCPJGFkHDSiUZ2ECyEbULU1JPwRfhJ/eDad 5A78apQqynuNwtnTGgd9vGS0g7ho6OraLC23CAxB0KiRc83kx/ sp2y/jiu6QTt1BQl4Pzoi1mpmQAZlRt731XXAl8wzlFGLYcOhT XmEUFW0+GDo01tDn4tjdw== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 27 July 2011, Will Newton wrote: > > > > Have you observed this behavior? The interrupt disable/enable should > > always come with a barrier that should prevent the bitops from > > leaking out, so I don't see how this causes problems in practice. > > Yes, although my arch does not have these barriers. Now I see from > memory-barriers.txt that lock/unlock are required to implement a > compiler barrier, sorry for the noise! Which architectures is this? Arnd