From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754833AbbDQRRU (ORCPT ); Fri, 17 Apr 2015 13:17:20 -0400 Received: from shards.monkeyblade.net ([149.20.54.216]:45202 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752449AbbDQRRT (ORCPT ); Fri, 17 Apr 2015 13:17:19 -0400 Date: Fri, 17 Apr 2015 13:17:12 -0400 (EDT) Message-Id: <20150417.131712.1245246947203158168.davem@davemloft.net> To: tj@kernel.org Cc: penguin-kernel@I-love.SAKURA.ne.jp, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCHSET] printk, netconsole: implement reliable netconsole From: David Miller In-Reply-To: <20150417162826.GB16743@htj.duckdns.org> References: <1429225433-11946-1-git-send-email-tj@kernel.org> <201504180035.AIJ09349.SOFFHFtLOOQVMJ@I-love.SAKURA.ne.jp> <20150417162826.GB16743@htj.duckdns.org> X-Mailer: Mew version 6.6 on Emacs 24.5 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Fri, 17 Apr 2015 10:17:17 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tejun Heo Date: Fri, 17 Apr 2015 12:28:26 -0400 > On Sat, Apr 18, 2015 at 12:35:06AM +0900, Tetsuo Handa wrote: >> If the sender side can wait for retransmission, why can't we use >> userspace programs (e.g. rsyslogd)? > > Because the system may be oopsing, ooming or threshing excessively > rendering the userland inoperable and that's exactly when we want > those log messages to be transmitted out of the system. If userland cannot run properly, it is almost certain that neither will your complex reliability layer logic. I tend to agree with Tetsuo, that in-kernel netconsole should remain as simple as possible and once it starts to have any smarts and less trivial logic the job belongs in userspace.