Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1766974AbXEBRxX (ORCPT ); Wed, 2 May 2007 13:53:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1766976AbXEBRxX (ORCPT ); Wed, 2 May 2007 13:53:23 -0400 Received: from agminet01.oracle.com ([141.146.126.228]:59459 "EHLO agminet01.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1766974AbXEBRxW (ORCPT ); Wed, 2 May 2007 13:53:22 -0400 Date: Wed, 2 May 2007 10:52:20 -0700 From: Bill Irwin To: "Eric W. Biederman" Cc: Bill Irwin , Jeremy Fitzhardinge , Andrew Morton , Dan Kruchinin , linux-kernel@vger.kernel.org, Jeremy Fitzhardinge , Andi Kleen , Ingo Molnar , wli@holomorphy.com Subject: Re: [RFC BUG?] dereference PAGE_OFFSET address (rc7-mm2) Message-ID: <20070502175220.GB26598@holomorphy.com> Mail-Followup-To: Bill Irwin , "Eric W. Biederman" , Jeremy Fitzhardinge , Andrew Morton , Dan Kruchinin , linux-kernel@vger.kernel.org, Jeremy Fitzhardinge , Andi Kleen , Ingo Molnar References: <20070502005140.b94500ff.akpm@linux-foundation.org> <20070502084617.GY26598@holomorphy.com> <20070502100600.GZ26598@holomorphy.com> <4638BC3E.9080708@goop.org> <20070502163244.GA26598@holomorphy.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.11 X-Brightmail-Tracker: AAAAAQAAAAI= X-Brightmail-Tracker: AAAAAQAAAAI= X-Whitelist: TRUE X-Whitelist: TRUE Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1676 Lines: 38 On Wed, May 02, 2007 at 09:28:46AM -0700, Jeremy Fitzhardinge wrote: >>> I think this should be fixed now. Eric made all those writes >>> unconditional (to fix a problem with PSE superpages not being created). >>> The patch is in Andi's queue. Bill Irwin writes: >> It needs verification with the testcase from this thread. On Wed, May 02, 2007 at 11:16:27AM -0600, Eric W. Biederman wrote: > Sounds reasonable. > However there is no reason to suspect it won't fix this case because > unconditional writes are what we have always done, and we have always > kept swapper_pg_dir from early boot as well. > In essence my patch I sent out to Andi was a partial revert. It would not be so far out to be aware of what pagetable entries were carried over from the initial swapper_pg_dir and explicitly clobber them (for instance, modifying their protection bits while otherwise retaining them). On Wed, May 02, 2007 at 11:16:27AM -0600, Eric W. Biederman wrote: > It isn't slated to go in until nextround but I also rewrote the early > page table setup in C. Allowing set_fixmap to work in the early > kernel, and fix problems of not having enough memory mapped to build > the identity mappings, because we are then updating the page table > we have also in the PAE case. I'm not sure when we run into those problems, though I understand what they are. I suppose it would be good to resolve them. -- wli - 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/