From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964908AbWFHSee (ORCPT ); Thu, 8 Jun 2006 14:34:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964929AbWFHSee (ORCPT ); Thu, 8 Jun 2006 14:34:34 -0400 Received: from news.cistron.nl ([62.216.30.38]:29406 "EHLO ncc1701.cistron.net") by vger.kernel.org with ESMTP id S964908AbWFHSee (ORCPT ); Thu, 8 Jun 2006 14:34:34 -0400 From: "Miquel van Smoorenburg" Subject: Re: Interrupts disabled for too long in printk Date: Thu, 8 Jun 2006 18:34:32 +0000 (UTC) Organization: Cistron Message-ID: References: <20060603111934.GA14581@Krystal> <9e4733910606080738xd44aab3o5ac0d4bda920575d@mail.gmail.com> <9e4733910606080845y48dabed1o333b82eeb1a57381@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-Trace: ncc1701.cistron.net 1149791672 14989 194.109.0.112 (8 Jun 2006 18:34:32 GMT) X-Complaints-To: abuse@cistron.nl X-Newsreader: trn 4.0-test76 (Apr 2, 2001) Originator: mikevs@n2o.xs4all.nl (Miquel van Smoorenburg) To: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org In article <9e4733910606080845y48dabed1o333b82eeb1a57381@mail.gmail.com>, Jon Smirl wrote: >This just seems to be an issue with the serial console implementation >which is much slower. So the answer looks to be that if the serial >console buffer is full, and it is being called with interrupts off, it >should just toss the printk. Read the serial console code. It is a standalone implementation completely seperate from the standard drivers, which deliberately turns off the interrupts and reverts to polling. This because there is no guarantee the whole irq handling stuff still works at the moment you're printk'ing a panic. Also the current standard serial drivers only work if the tty has been opened by a userspace process. If you want to change this, first fix the latter problem, then change the serial console output driver so that it uses the standard serial driver for lower priority messages and only uses the polling code for panics. Mike.