From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D70CC43334 for ; Tue, 4 Sep 2018 07:16:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 41AA320869 for ; Tue, 4 Sep 2018 07:16:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 41AA320869 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727196AbeIDLkO (ORCPT ); Tue, 4 Sep 2018 07:40:14 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:37470 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726205AbeIDLkN (ORCPT ); Tue, 4 Sep 2018 07:40:13 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id F327087927; Tue, 4 Sep 2018 07:16:24 +0000 (UTC) Received: from localhost (ovpn-8-22.pek2.redhat.com [10.72.8.22]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 323962023416; Tue, 4 Sep 2018 07:16:23 +0000 (UTC) Date: Tue, 4 Sep 2018 15:16:20 +0800 From: Baoquan He To: "H. Peter Anvin" Cc: kirill.shutemov@linux.intel.com, x86@kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@kernel.org Subject: Re: [PATCH 1/3] x86/boot: Add bit fields into xloadflags for 5-level kernel checking Message-ID: <20180904071620.GL1740@192.168.1.3> References: <20180829141624.13985-1-bhe@redhat.com> <20180829141624.13985-2-bhe@redhat.com> <6ea94875-ae07-6220-eb3e-d3f830cdac03@zytor.com> <20180904034414.GI1740@192.168.1.3> <4546fc39-4982-4c91-c812-0df1e9bc9e20@zytor.com> <20180904052036.GJ1740@192.168.1.3> <20180904060649.GK1740@192.168.1.3> <44fc1530-eb88-d8c5-7465-e48c91799a98@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <44fc1530-eb88-d8c5-7465-e48c91799a98@zytor.com> User-Agent: Mutt/1.9.1 (2017-09-22) X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Tue, 04 Sep 2018 07:16:25 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Tue, 04 Sep 2018 07:16:25 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'bhe@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/03/18 at 11:36pm, H. Peter Anvin wrote: > On 09/03/18 23:06, Baoquan He wrote: > >> > >> That makes no sense. I'm talking about *entering* the kernel; the second > >> kernel should switch to 5-level mode as necessary. > > > > OK, I didn't get your point. I forget what difficulty was met so that > > Kirill need to take this way. In that way, we will never have chance to > > put kernel above 64TB even from 5-level kernel to jump to 5-level > > kernel. > > > > It sounds like you have no intent of doing that anyway? Now, that is > something one could use an xloadflag for, as I previously stated: "this kernel > supports being entered in 5-level mode." I am willing to take any better way to improve. May need to make clear why that was not taken. Not sure if Kirill still has the details. Thanks Baoquan