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=-0.4 required=3.0 tests=BUG6152_INVALID_DATE_TZ_ABSURD,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS,INVALID_DATE_TZ_ABSURD,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 30593C433E0 for ; Thu, 2 Jul 2020 09:02:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 024FD2088E for ; Thu, 2 Jul 2020 09:02:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Dm6t6Oj3"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Jzif+nd6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726819AbgGBJCF (ORCPT ); Thu, 2 Jul 2020 05:02:05 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:47408 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725774AbgGBJCF (ORCPT ); Thu, 2 Jul 2020 05:02:05 -0400 From: John Ogness DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1593680523; 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: in-reply-to:in-reply-to:references:references; bh=iSHp+qL8jlCnfx+lpGtQHzsTwnPkgJZ+hzplODbpLis=; b=Dm6t6Oj3BbIVrKAKyTPjW9LF/T6t9Bdmutb1cDd//FSn6oQed1lqlut+QZ/bL6vcaNKAmJ z0JGzBsNfDxwFugQRGwERqzKuxAK3zrNqmSLEQ2pdwKWeClLJCsnQZKmxgOiIdd1ftbaQW WlKM7WI3QfY26qqotnC2lsXHy7rhQRghAbA+3li6yeObek2Ek+dXKjK4UXsZAfoOhfnKVK 1r8SBDbFHUYJBrENZduuXCsHqzEGTfM+oDtvoSQ3nqff6jUoPfhcM++KrFwNh8q7bMYXfq /4I3bzmlge/U+LaUPvcl+ROpiqtDlKixRwaTPUM4finRSAVGrP6/1W4U8DfulQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1593680523; 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: in-reply-to:in-reply-to:references:references; bh=iSHp+qL8jlCnfx+lpGtQHzsTwnPkgJZ+hzplODbpLis=; b=Jzif+nd6FqtafDb6f+2yMZZidwaOxAfVki88jUDsJxCrf3uwlXuFSQCViQifPGUGQtg947 TVMYm9euQgiGUHCA== To: lijiang , 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 Subject: Re: [PATCH v3 3/3] printk: use the lockless ringbuffer In-Reply-To: References: <20200618144919.9806-1-john.ogness@linutronix.de> <20200618144919.9806-4-john.ogness@linutronix.de> Date: Thu, 02 Jul 2020 11:08:02 +0206 Message-ID: <87zh8imgs5.fsf@jogness.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Yes, a patch for this is needed (as well as for any other related software floating around the internet). I have no RFC patches for vmcore-dmesg. Looking at the code, I think it would be quite straight forward to port the makedumpfile patch. I will try to make some time for this. I do not want to patch any other software for this. I think with 3 examples (crash, makedumpfile, vmcore-dmesg), others should be able to implement the changes to their software without needing my help. John Ogness