Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758549AbYAQWH0 (ORCPT ); Thu, 17 Jan 2008 17:07:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757986AbYAQWG4 (ORCPT ); Thu, 17 Jan 2008 17:06:56 -0500 Received: from outbound-va3.frontbridge.com ([216.32.180.16]:43369 "EHLO outbound5-va3-R.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757876AbYAQWGy (ORCPT ); Thu, 17 Jan 2008 17:06:54 -0500 X-BigFish: VP X-MS-Exchange-Organization-Antispam-Report: OrigIP: 163.181.251.8;Service: EHS X-Server-Uuid: DF9F24A0-1A5C-40A5-8B0A-DEB676E72ECF Date: Thu, 17 Jan 2008 23:06:50 +0100 From: "Andreas Herrmann3" To: "Ingo Molnar" cc: "Siddha, Suresh B" , "Venki Pallipadi" , ak@muc.de, ebiederm@xmission.com, rdreier@cisco.com, torvalds@linux-foundation.org, gregkh@suse.de, airlied@skynet.ie, davej@redhat.com, tglx@linutronix.de, hpa@zytor.com, akpm@linux-foundation.org, arjan@infradead.org, jesse.barnes@intel.com, davem@davemloft.net, linux-kernel@vger.kernel.org Subject: Re: [patch 0/4] x86: PAT followup - Incremental changes and bug fixes Message-ID: <20080117220650.GE12631@alberich.amd.com> References: <20080116023955.597433000@intel.com> <20080116185748.GA11244@alberich.amd.com> <20080116203328.GA17869@linux-os.sc.intel.com> <20080117191211.GA12631@alberich.amd.com> <20080117203600.GB27778@elte.hu> <20080117210301.GC12631@alberich.amd.com> <20080117211308.GA7858@elte.hu> <20080117213131.GA25389@linux-os.sc.intel.com> <20080117214209.GA12811@elte.hu> MIME-Version: 1.0 In-Reply-To: <20080117214209.GA12811@elte.hu> User-Agent: Mutt/1.5.16 (2007-06-09) X-OriginalArrivalTime: 17 Jan 2008 22:06:34.0614 (UTC) FILETIME=[39290160:01C85955] X-WSS-ID: 6B910EE707S8365221-01-01 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1070 Lines: 29 On Thu, Jan 17, 2008 at 10:42:09PM +0100, Ingo Molnar wrote: > > * Siddha, Suresh B wrote: > > > On Thu, Jan 17, 2008 at 10:13:08PM +0100, Ingo Molnar wrote: > > > but in general we must be robust enough in this case and just degrade > > > any overlapping page to UC (and emit a warning perhaps) - instead of > > > failing the ioremap and thus failing the driver (and the bootup). > > > > But then, this will cause an attribute conflicit. Old one was > > specifying WB in PAT (ioremap with noflags) and the new ioremap > > specifies UC. > > we could fix up all aliases of that page as well and degrade them to UC? Yes, we must fix all aliases or reject the conflicting mapping. But fixing all aliases might not be that easy. (I've just seen a panic when using your patch ;-( Andreas -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/