Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932321AbWEXQGJ (ORCPT ); Wed, 24 May 2006 12:06:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932736AbWEXQGJ (ORCPT ); Wed, 24 May 2006 12:06:09 -0400 Received: from gateway-1237.mvista.com ([63.81.120.158]:56535 "EHLO gateway-1237.mvista.com") by vger.kernel.org with ESMTP id S932321AbWEXQGI (ORCPT ); Wed, 24 May 2006 12:06:08 -0400 Subject: Re: Ingo's realtime_preempt patch causes kernel oops From: Daniel Walker To: Steven Rostedt Cc: Sven-Thorsten Dietrich , tglx@linutronix.de, Yann.LEPROVOST@wavecom.fr, linux-kernel@vger.kernel.org, linux-kernel-owner@vger.kernel.org, Ingo Molnar In-Reply-To: <1148485943.24623.54.camel@localhost.localdomain> References: <1148475334.24623.45.camel@localhost.localdomain> <1148476383.5239.54.camel@localhost.localdomain> <1148484729.14683.5.camel@localhost.localdomain> <1148485943.24623.54.camel@localhost.localdomain> Content-Type: text/plain Date: Wed, 24 May 2006 09:06:03 -0700 Message-Id: <1148486764.3535.145.camel@c-67-180-134-207.hsd1.ca.comcast.net> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 958 Lines: 22 > Would IRQs stay masked until the thread has finished running? > > I would say yes. But the system is basically broken if you have the > same interrupt line that needs both to be threaded and NODELAY. It's certainly less than and ideal situation .. If set an interrupt as SA_NODELAY you'd think that it's suppose to be high priority , but then you share it with something that's not high high priority which doesn't make a lot of sense .. However, the PCI bus doesn't (as far as I know) allow for interrupts to easily be isolated .. So, with PCI, you may end up with potentially high priority interrupts shared with some other interrupt .. So it is a situation that could happen, maybe even often . Daniel - 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/