From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764088AbXGFU20 (ORCPT ); Fri, 6 Jul 2007 16:28:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762333AbXGFU2S (ORCPT ); Fri, 6 Jul 2007 16:28:18 -0400 Received: from gw.goop.org ([64.81.55.164]:56043 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761037AbXGFU2S (ORCPT ); Fri, 6 Jul 2007 16:28:18 -0400 Message-ID: <468EA5E0.4070501@goop.org> Date: Fri, 06 Jul 2007 13:28:16 -0700 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.4 (X11/20070615) MIME-Version: 1.0 To: Zachary Amsden CC: Chris Wright , Andrew Morton , Linux Kernel Mailing List , virtualization@lists.osdl.org, Stefan Richter , "Robert P. J. Day" Subject: Re: [PATCH] VMI: remove CONFIG_DEBUG_PAGE_TYPE and associated bitrotted code References: <468E890A.1070504@s5r6.in-berlin.de> <20070706201625.GT4306@sequoia.sous-sol.org> <468EA27C.9060401@vmware.com> In-Reply-To: <468EA27C.9060401@vmware.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Zachary Amsden wrote: > I'd rather keep it, even with bitrot - it was non-trivial to get > correct, and found many surprises in the code; most notably, it can > detect > > 1) PTE writes to pages not declared as page tables > 2) Failure to allocate or de-allocate page tables using the > paravirt-ops API > 3) PTE writes using the wrong level operations > > These are most useful properties; in fact, I would like to extend the > code for 64-bit paravirt-ops and 4-level paging, so rather not kill it > until then. > > I never merged the whole bit upstream because it added a field to > struct page. Hm, is that a big problem? It would be OK for a debug config option, wouldn't it? Also, it doesn't seem particularly vmi-specific. Could it be made part of the pvops infrastructure? J