Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932603AbWEXOEY (ORCPT ); Wed, 24 May 2006 10:04:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932630AbWEXOEX (ORCPT ); Wed, 24 May 2006 10:04:23 -0400 Received: from wmp-pc40.wavecom.fr ([81.80.89.162]:32007 "EHLO domino.wavecom.fr") by vger.kernel.org with ESMTP id S932603AbWEXOEX (ORCPT ); Wed, 24 May 2006 10:04:23 -0400 In-Reply-To: <1148475334.24623.45.camel@localhost.localdomain> Subject: Re: Ingo's realtime_preempt patch causes kernel oops To: Steven Rostedt Cc: Daniel Walker , linux-kernel@vger.kernel.org, linux-kernel-owner@vger.kernel.org, Ingo Molnar , Thomas Gleixner X-Mailer: Lotus Notes Release 6.5.1 January 21, 2004 Message-ID: From: Yann.LEPROVOST@wavecom.fr Date: Wed, 24 May 2006 15:58:18 +0200 X-MIMETrack: Serialize by Router on domino/wavecom(Release 6.5.4|March 27, 2005) at 05/24/2006 03:58:20 PM MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3011 Lines: 71 Yeah, I'm using minicom to log in through the serial debug unit, meaning that there are probably many incoming intterrupts corresponding to input characters... Yann Steven Rostedt To Yann.LEPROVOST@wavecom.fr 24/05/2006 14:55 cc Daniel Walker , linux-kernel@vger.kernel.org, linux-kernel-owner@vger.kernel.org, Ingo Molnar , Thomas Gleixner Subject Re: Ingo's realtime_preempt patch causes kernel oops On Wed, 2006-05-24 at 10:06 +0200, Yann.LEPROVOST@wavecom.fr wrote: > The debug serial unit is part of the mainline kernel, this is the common > link to work with the CSB637 Cogent board. > I don't know about others AT91RM9200 based board. > > AT91RM9200 also have others USART, but there are no available output > connectors on the CSB637 board. > Hi Yann, OK, do you only get the prints from the serial? If so than that is OK, but if you also log in through the serial, then that is a problem. In other words, do you have something like mgetty running to log in through the serial? Looking at the at91_interrupt it can call mutex spin_locks if receiving data. So this needs care. Thomas or Ingo, Maybe the handling of IRQs needs to handle the case that shared irq can have both a NODELAY and a thread. The irq descriptor could have a NODELAY set if any of the actions are NODELAY, but before calling the interrupt handler (in interrupt context), check if the action is NODELAY or not, and if not, wake up the thread if not done so already. thoughts? -- Steve - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/