From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754052Ab1LVBAB (ORCPT ); Wed, 21 Dec 2011 20:00:01 -0500 Received: from wolverine02.qualcomm.com ([199.106.114.251]:44044 "EHLO wolverine02.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752149Ab1LVA76 (ORCPT ); Wed, 21 Dec 2011 19:59:58 -0500 X-IronPort-AV: E=McAfee;i="5400,1158,6567"; a="146755371" Date: Wed, 21 Dec 2011 16:59:56 -0800 From: David Brown To: Tim Bird Cc: linux-embedded , linux kernel , Arnd Bergmann , john stultz , Greg KH , Brian Swetland Subject: Re: RFC: android logger feedback request Message-ID: <20111222005956.GA4862@codeaurora.org> References: <4EF264C3.6000104@am.sony.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4EF264C3.6000104@am.sony.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 21, 2011 at 02:59:15PM -0800, Tim Bird wrote: > In Android, this system uses a fixed set of device nodes with > well-known names: /dev/log/main, /dev/log/events, /dev/log/radio > and /dev/log/system. These names seem very specific to Android's use case. Would we want the mechanism to be more general, or configurable, so that another embedded-type system would be able to have their own log types. But, the biggest question I have is to understand why this is a kernel driver. In essence, it is just shuttling data from various processes to something that eventually needs to read that data. In other words, it is doing a subset of what syslog does. If the concern is about a userspace program crashing, wouldn't the userspace tool that reads this data also be able to crash? The driver clearly has no kernel API, since it exports no symbols. I could see more of an argument for it if certain kernel things were able to write to the log, but then we are also duplicating other functionality. David -- Sent by an employee of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.