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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 CC5C3C04EB9 for ; Wed, 5 Dec 2018 14:21:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 97D472081C for ; Wed, 5 Dec 2018 14:21:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 97D472081C 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 S1727707AbeLEOVe (ORCPT ); Wed, 5 Dec 2018 09:21:34 -0500 Received: from mx1.redhat.com ([209.132.183.28]:55732 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726918AbeLEOVd (ORCPT ); Wed, 5 Dec 2018 09:21:33 -0500 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6091537E87; Wed, 5 Dec 2018 14:21:33 +0000 (UTC) Received: from localhost.localdomain (ovpn-12-56.pek2.redhat.com [10.72.12.56]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A65F91001F54; Wed, 5 Dec 2018 14:21:17 +0000 (UTC) Subject: Re: [PATCH 1/2 v2] kdump: add the vmcoreinfo documentation To: Borislav Petkov Cc: linux-kernel@vger.kernel.org, kexec@lists.infradead.org, tglx@linutronix.de, mingo@redhat.com, x86@kernel.org, akpm@linux-foundation.org, bhe@redhat.com, dyoung@redhat.com, Jonathan Corbet , linux-doc@vger.kernel.org References: <20181202030839.29945-1-lijiang@redhat.com> <20181202030839.29945-2-lijiang@redhat.com> <20181203150809.GA4794@zn.tnic> <779dbae7-f6e2-e9e4-bdd0-0a9e6ec62487@redhat.com> <20181205113032.GF29510@zn.tnic> From: lijiang Message-ID: <3d1a7e68-34c5-d118-fe09-7c9bc14cce84@redhat.com> Date: Wed, 5 Dec 2018 22:21:12 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20181205113032.GF29510@zn.tnic> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Wed, 05 Dec 2018 14:21:33 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2018年12月05日 19:30, Borislav Petkov 写道: > On Tue, Dec 04, 2018 at 05:35:09PM +0800, lijiang wrote: >> There are more people to review and improve this document together, that would >> be fine. > > That's basically kernel development :) > >> Generating VMCOREINFO is easy in the first kernel, for example: >> # makedumpfile -g VMCOREINFO -x vmlinux > > I get: > > $ makedumpfile -g VMCOREINFO -x vmlinux > The kernel version is not supported. > The makedumpfile operation may be incomplete. > > The vmcoreinfo is saved to VMCOREINFO. > > makedumpfile Completed. > > But the text file looks ok AFAICT. Please add that command to the > documentation file. > Ok, no problem. >> For these two *why*, it should be easy to understand. Because user-space tools >> need to know basic information, such as the symbol values, field offset, structure >> size, etc. Otherwise, these tools won't know how to analyze the memory of the crash >> kernel. > > That's clear. The question is *why* *exactly* is every piece of export > needed. > >> For the second question 'how they are used', we can get the answer >> from user-space tools, such as makedumpfile, crash tools. Therefore, >> it may not need to explain any more in kernel document. On the other >> hand, if we must put these contents into kernel document, i have to >> say, that would be a hard task. > > You can put one or two sentences for each, stating what they're used > for. This way, people can go and look up makedumpfile source code for > further info and people trying to add new items to VMCOREINFO can look > in this documentation here first to figure out whether maybe the info > they need has been exported already. > This is a considerate suggestion. I will try my best to do that. Thanks. Lianbo. > Thx. >