From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757327AbZKBXf4 (ORCPT ); Mon, 2 Nov 2009 18:35:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757208AbZKBXf4 (ORCPT ); Mon, 2 Nov 2009 18:35:56 -0500 Received: from mx1.redhat.com ([209.132.183.28]:41130 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757186AbZKBXfz (ORCPT ); Mon, 2 Nov 2009 18:35:55 -0500 Message-ID: <4AEF6CC3.4000508@redhat.com> Date: Mon, 02 Nov 2009 18:35:31 -0500 From: Rik van Riel Organization: Red Hat, Inc User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.4pre) Gecko/20090922 Fedora/3.0-3.9.b4.fc12 Lightning/1.0pre Thunderbird/3.0b4 MIME-Version: 1.0 To: Avi Kivity CC: Ingo Molnar , Gleb Natapov , kvm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, "H. Peter Anvin" , Thomas Gleixner Subject: Re: [PATCH 02/11] Add "handle page fault" PV helper. References: <1257076590-29559-1-git-send-email-gleb@redhat.com> <1257076590-29559-3-git-send-email-gleb@redhat.com> <20091102092214.GB8933@elte.hu> <4AEF2D0A.4070807@redhat.com> <4AEF3419.1050200@redhat.com> In-Reply-To: <4AEF3419.1050200@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/02/2009 02:33 PM, Avi Kivity wrote: > On 11/02/2009 09:03 PM, Rik van Riel wrote: >>> This patch is not acceptable unless it's done cleaner. Currently we >>> already have 3 callbacks in do_page_fault() (kmemcheck, mmiotrace, >>> notifier), and this adds a fourth one. >> >> >> There's another alternative - add our own exception vector >> for async page faults. Not sure if that is warranted though, >> especially if we already have other callbacks in do_page_fault() >> and we can consolidate them. >> > > We can't add an exception vector since all the existing ones are either > taken or reserved. I believe some are reserved for operating system use. That means the guest can pick one and tell the host to use that one to notify it. -- All rights reversed.