From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933428AbcA0O5V (ORCPT ); Wed, 27 Jan 2016 09:57:21 -0500 Received: from mx1.redhat.com ([209.132.183.28]:37325 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932555AbcA0O5S convert rfc822-to-8bit (ORCPT ); Wed, 27 Jan 2016 09:57:18 -0500 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <20160127083546.GJ6357@twins.programming.kicks-ass.net> References: <20160127083546.GJ6357@twins.programming.kicks-ass.net> <5696BA6E.4070508@imgtec.com> <20160114120445.GB15828@arm.com> <56980145.5030901@imgtec.com> <20160114204827.GE3818@linux.vnet.ibm.com> <56981212.7050301@imgtec.com> <20160114222046.GH3818@linux.vnet.ibm.com> <20160126102402.GE6357@twins.programming.kicks-ass.net> <20160126103200.GI6375@twins.programming.kicks-ass.net> <20160126110053.GA21553@arm.com> <20160126201143.GV4503@linux.vnet.ibm.com> To: Peter Zijlstra Cc: dhowells@redhat.com, "Paul E. McKenney" , Will Deacon , Leonid Yegoshin , "Michael S. Tsirkin" , linux-kernel@vger.kernel.org, Arnd Bergmann , linux-arch@vger.kernel.org, Andrew Cooper , Russell King - ARM Linux , virtualization@lists.linux-foundation.org, Stefano Stabellini , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Joe Perches , David Miller , linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-metag@vger.kernel.org, linux-mips@linux-mips.org, x86@kernel.org, user-mode-linux-devel@lists.sourceforge.net, adi-buildroot-devel@lists.sourceforge.net, linux-sh@vger.kernel.org, linux-xtensa@linux-xtensa.org, xen-devel@lists.xenproject.org, Ralf Baechle , Ingo Molnar , ddaney.cavm@gmail.com, james.hogan@imgtec.com, Michael Ellerman Subject: Re: [PATCH] documentation: Add disclaimer MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <15881.1453906627.1@warthog.procyon.org.uk> Content-Transfer-Encoding: 8BIT Date: Wed, 27 Jan 2016 14:57:07 +0000 Message-ID: <15882.1453906627@warthog.procyon.org.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Peter Zijlstra wrote: > +========== > +DISCLAIMER > +========== > + > +This document is not a specification; it is intentionally (for the sake of > +brevity) and unintentionally (due to being human) incomplete. This document is > +meant as a guide to using the various memory barriers provided by Linux, but > +in case of any doubt (and there are many) please ask. > + > +I repeat, this document is not a specification of what Linux expects from > +hardware. The purpose of this document is twofold: (1) to specify the minimum functionality that one can rely on for any particular barrier, and (2) to provide a guide as to how to use the barriers that are available. Note that an architecture can provide more than the minimum requirement for any particular barrier, but if the barrier provides less than that, it is incorrect. Note also that it is possible that a barrier may be a no-op for an architecture because the way that arch works renders an explicit barrier unnecessary in that case. > + Can you bung an extra blank line in here if you have to redo this at all? > +======== > +CONTENTS > +======== > > (*) Abstract memory access model. > David