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=-7.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,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 2EFFFC433DF for ; Wed, 8 Jul 2020 05:51:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 02764206E2 for ; Wed, 8 Jul 2020 05:51:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Mr1ShgOn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729698AbgGHFvI (ORCPT ); Wed, 8 Jul 2020 01:51:08 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:25445 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726278AbgGHFvH (ORCPT ); Wed, 8 Jul 2020 01:51:07 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594187466; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=d0KhoKnMNC3+EgedwCLIMtHsloIf+grtGbdl24ZJeSg=; b=Mr1ShgOnppbnpJ4jjb2MtS2bHvPMmQc019agyCMCB0FkZFprjZ3iG82r8V3BvSADllM9b+ ZL0dzus9/f9D0DxMAuGzu9Q0Bjd0i0MXqNxSDcJ3JUKxCbjImLuyDjcgFTDaf2BHlGoM5p 7rOcR/tABM9L6V6kYttFfxuic7yv8+8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-307-YK-WKQQfNGC_uf2jsFPfDg-1; Wed, 08 Jul 2020 01:51:02 -0400 X-MC-Unique: YK-WKQQfNGC_uf2jsFPfDg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id BF83E87950F; Wed, 8 Jul 2020 05:51:00 +0000 (UTC) Received: from localhost.localdomain (ovpn-13-13.pek2.redhat.com [10.72.13.13]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7F02660CD1; Wed, 8 Jul 2020 05:50:55 +0000 (UTC) Subject: Re: [PATCH v3 3/3] printk: use the lockless ringbuffer To: John Ogness , Petr Mladek Cc: Peter Zijlstra , Sergey Senozhatsky , Sergey Senozhatsky , Steven Rostedt , Linus Torvalds , Greg Kroah-Hartman , Andrea Parri , Thomas Gleixner , Paul McKenney , kexec@lists.infradead.org, linux-kernel@vger.kernel.org References: <20200618144919.9806-1-john.ogness@linutronix.de> <20200618144919.9806-4-john.ogness@linutronix.de> <87zh8imgs5.fsf@jogness.linutronix.de> <585a6a1b-931c-1034-e2cc-da2c4381751e@redhat.com> <87lfk0stiw.fsf@jogness.linutronix.de> From: lijiang Message-ID: <0733578f-1f9d-bbd4-0c30-a8a124f5ffa8@redhat.com> Date: Wed, 8 Jul 2020 13:50:51 +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: <87lfk0stiw.fsf@jogness.linutronix.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2020年07月03日 19:54, John Ogness 写道: > On 2020-07-02, lijiang wrote: >> About the VMCOREINFO part, I made some tests based on the kernel patch >> v3, the makedumpfile and crash-utility can work as expected with your >> patch(userspace patch), but, unfortunately, the >> vmcore-dmesg(kexec-tools) can't correctly read the printk ring buffer >> information, and get the following error: >> >> "Missing the log_buf symbol" >> >> The kexec-tools(vmcore-dmesg) should also have a similar patch, just like >> in the makedumpfile and crash-utility. > > A patched kexec-tools is available here [0]. > > I did not test using 32-bit dumps on 64-bit machines and vice versa. But > it should work. > > John Ogness > > [0] https://github.com/Linutronix/kexec-tools.git (printk branch) > After applying this patch, the vmcore-dmesg can work. Thank you, John Ogness.