From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755787Ab2LMXss (ORCPT ); Thu, 13 Dec 2012 18:48:48 -0500 Received: from terminus.zytor.com ([198.137.202.10]:40744 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754660Ab2LMXsr (ORCPT ); Thu, 13 Dec 2012 18:48:47 -0500 Message-ID: <50CA6918.5060806@zytor.com> Date: Thu, 13 Dec 2012 15:47:36 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Yinghai Lu CC: Thomas Gleixner , Ingo Molnar , "Eric W. Biederman" , Andrew Morton , linux-kernel@vger.kernel.org, Konrad Rzeszutek Wilk , Stefano Stabellini Subject: Re: [PATCH v6 00/27] x86, boot, 64bit: Add support for loading ramdisk and bzImage above 4G References: <1355436141-8668-1-git-send-email-yinghai@kernel.org> In-Reply-To: <1355436141-8668-1-git-send-email-yinghai@kernel.org> 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 There are obviously good bits to this patchset, but I'm really starting to think the "pseudo-linear mode" via a trap handler -- meaning we can access all of memory without any extra effort -- makes more sense. In fact, that way we could just build the full page tables without worrying about incremental bootstrap, depending on if that is a complexity win or not. Either way, this is for native only: the Xen domain builder or other similar entry paths should be setting up page tables that cover all of memory; I'm hoping Konrad and Stefano can confirm this. The only reason to go with another approach I can think of is if it makes 32/64-bit unification cleaner. -hpa