Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760508AbcCELxH (ORCPT ); Sat, 5 Mar 2016 06:53:07 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:35239 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753628AbcCELxB (ORCPT ); Sat, 5 Mar 2016 06:53:01 -0500 Date: Sat, 5 Mar 2016 12:52:55 +0100 From: Ingo Molnar To: "Luis R. Rodriguez" Cc: paulmck@linux.vnet.ibm.com, bp@alien8.de, tglx@linutronix.de, hpa@zytor.com, toshi.kani@hp.com, airlied@redhat.com, benh@kernel.crashing.org, mst@redhat.com, vinod.koul@intel.com, jgross@suse.com, daniel.vetter@ffwll.ch, luto@amacapital.net, davem@davemloft.net, ben@decadent.org.uk, benjamin.poirier@gmail.com, linux-fbdev@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, linux-doc@vger.kernel.org, corbet@lwn.net Subject: Re: [PATCH v2] x86: PAT: Documentation: rewrite "MTRR effects on PAT / non-PAT systems" Message-ID: <20160305115255.GA11846@gmail.com> References: <20160304210900.GT3577@linux.vnet.ibm.com> <1457131501-14855-1-git-send-email-mcgrof@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1457131501-14855-1-git-send-email-mcgrof@kernel.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 623 Lines: 17 * Luis R. Rodriguez wrote: > The current documentation refers to using set_memory_wc() as a > possible hole strategy when you have overlapping ioremap() regions, The whole explanation should talk about virtual aliases over the same physical address, not some 'overlapping regions'. I see where this talk about 'overlap' comes: the memtype rbtree in arch/x86/mm/pat_rbtree.c indeed has memtype ranges that may overlap on the physical side. But it is highly confusing to call this 'overlapping' on the driver API documentation level without making it really clear what it's about. Thanks, Ingo