Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752738AbdI3DOj (ORCPT ); Fri, 29 Sep 2017 23:14:39 -0400 Received: from mail-pg0-f50.google.com ([74.125.83.50]:49462 "EHLO mail-pg0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752653AbdI3DOi (ORCPT ); Fri, 29 Sep 2017 23:14:38 -0400 X-Google-Smtp-Source: AOwi7QDS3VWePt45q0fCiHfVhI0F4V55mtSkOLlJanaLHWbwxcWOir2xBF5u/1WyUM+oEyVnyo8DuA== Date: Sat, 30 Sep 2017 12:14:34 +0900 From: Sergey Senozhatsky To: pierre kuo Cc: Sergey Senozhatsky , Petr Mladek , Sergey Senozhatsky , rostedt@goodmis.org, linux-kernel@vger.kernel.org Subject: Re: [RFC V2] printk: add warning while drop partial text in msg Message-ID: <20170930031434.GA490@tigerII.localdomain> References: <1501421870-12042-1-git-send-email-vichy.kuo@gmail.com> <20170801024303.GA469@jagdpanzerIV.localdomain> <20170817010541.GA20907@jagdpanzerIV.localdomain> <20170918093905.GB1514@jagdpanzerIV.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 549 Lines: 14 On (09/27/17 21:59), pierre kuo wrote: [..] > We use the example in this mail since we try to collect the message at > different places in our driver. > And batch to printk for saving individual output time and group > message together. I see. well, printk batching (buffered mode) is a bit tricky and we don't have it, nor we recommend it. the main problem - you lose your data on panic. it seems to me, that the only way to do it is to re-use printk-safe buffer on that particular CPU. but it comes at a price and in general is a bit ugly. -ss