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=-8.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 16E3FC4360C for ; Thu, 26 Sep 2019 15:20:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DAB35222C6 for ; Thu, 26 Sep 2019 15:20:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="QPr6feej" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727263AbfIZPUh (ORCPT ); Thu, 26 Sep 2019 11:20:37 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:54296 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726029AbfIZPUh (ORCPT ); Thu, 26 Sep 2019 11:20:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To: Subject:Sender:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=yLzCCbA1xxgfSSaN55ak3+kri+HafX9octEvTxgZHQ4=; b=QPr6feejBrc5AYDFCfltGGA9g MOBKVaJNT8g359mo5ovvj7SADpWggwaleaynmHTmIYrP0Dvoza9azT1TCvicyZuy9cv5sANCwT5W3 FF2mFDgv3fPhc3hN6hocoT+L4rJuD25u1PZbE61MAfmTXHNk8R0mjCVermC1hgulxsQNBhNEldsMD gh4TwP/rzW80LblNU6jyYPgNR+2MnxFo+EM6EDSKKJdOEXsKzFiYZ3MsDbGNPX2nYvsefFcRJhyB3 ZBi7dDMANOsy7GNmE1geqRK3jmUBJTtd4fcii6HYFMX87s2QXBhODXtm8z67ADOVa6PpQGLnU6pDf OrGBGwJzA==; Received: from [2601:1c0:6280:3f0::9a1f] by bombadil.infradead.org with esmtpsa (Exim 4.92.2 #3 (Red Hat Linux)) id 1iDVZF-00039v-NT; Thu, 26 Sep 2019 15:20:29 +0000 Subject: Re: [RFC PATCH] x86/doc/boot_protocol: Correct the description of "reloc" To: hpa@zytor.com, Cao jin , Ingo Molnar Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, corbet@lwn.net References: <20190926042116.17929-1-caoj.fnst@cn.fujitsu.com> <20190926060139.GA100481@gmail.com> <3073CD01-65C5-4BEC-B2FC-F76DD0E70D73@zytor.com> From: Randy Dunlap Message-ID: Date: Thu, 26 Sep 2019 08:20:28 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <3073CD01-65C5-4BEC-B2FC-F76DD0E70D73@zytor.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/26/19 12:58 AM, hpa@zytor.com wrote: > On September 26, 2019 12:55:51 AM PDT, Cao jin wrote: >> On 9/26/19 2:01 PM, Ingo Molnar wrote: >>> * Cao jin wrote: >>> >>>> The fields marked with (reloc) actually are not dedicated for >> writing, >>>> but communicating info for relocatable kernel with boot loaders. For >>>> example: >>>> >>>> ============ ============ >>>> Field name: pref_address >>>> Type: read (reloc) >>>> Offset/size: 0x258/8 >>>> Protocol: 2.10+ >>>> ============ ============ >>>> >>>> ============ ======================== >>>> Field name: code32_start >>>> Type: modify (optional, reloc) >>>> Offset/size: 0x214/4 >>>> Protocol: 2.00+ >>>> ============ ======================== >>>> >>>> Signed-off-by: Cao jin >>>> --- >>>> Unless I have incorrect non-native understanding for "fill in", I >> think >>>> this is inaccurate. >>>> >>>> Documentation/x86/boot.rst | 2 +- >>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>> >>>> diff --git a/Documentation/x86/boot.rst b/Documentation/x86/boot.rst >>>> index 08a2f100c0e6..a611bf04492d 100644 >>>> --- a/Documentation/x86/boot.rst >>>> +++ b/Documentation/x86/boot.rst >>>> @@ -243,7 +243,7 @@ bootloader ("modify"). >>>> >>>> All general purpose boot loaders should write the fields marked >>>> (obligatory). Boot loaders who want to load the kernel at a >>>> -nonstandard address should fill in the fields marked (reloc); other >>>> +nonstandard address should consult with the fields marked (reloc); >> other >>>> boot loaders can ignore those fields. >>>> >>>> The byte order of all fields is littleendian (this is x86, after >> all.) >>> >>> Well, this documentation is written from the point of view of a >>> *bootloader*, not the kernel. So the 'fill in' says that the >> bootloader >>> should write those fields - which is correct, right? >>> >> >> Take pref_address or relocatable_kernel for example, they have type: >> read (reloc), does boot loader need to write them? I don't see grub >> does >> this at least. > > Read means the boot later reads them. is that boot loader ?? -- ~Randy