Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261307AbVEIMNi (ORCPT ); Mon, 9 May 2005 08:13:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261311AbVEIMNi (ORCPT ); Mon, 9 May 2005 08:13:38 -0400 Received: from mx2.elte.hu ([157.181.151.9]:10458 "EHLO mx2.elte.hu") by vger.kernel.org with ESMTP id S261307AbVEIMNg (ORCPT ); Mon, 9 May 2005 08:13:36 -0400 Date: Mon, 9 May 2005 14:13:24 +0200 From: Ingo Molnar To: kus Kusche Klaus Cc: linux-kernel@vger.kernel.org, dwalker@mvista.com Subject: Re: Real-Time Preemption: Magic Sysrq p doesn't work Message-ID: <20050509121324.GA20941@elte.hu> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.1i X-ELTE-SpamVersion: MailScanner 4.31.6-itk1 (ELTE 1.2) SpamAssassin 2.63 ClamAV 0.73 X-ELTE-VirusStatus: clean X-ELTE-SpamCheck: no X-ELTE-SpamCheck-Details: score=-4.9, required 5.9, autolearn=not spam, BAYES_00 -4.90 X-ELTE-SpamLevel: X-ELTE-SpamScore: -4 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 763 Lines: 20 * kus Kusche Klaus wrote: > While testing, I noticed that Sysrq p is silently ignored on current > RT kernels with RT preemption: The syslog contains a message that > Sysrq p was pressed, but no registers are printed. yes, that's because the keyboard interrupt is 'threaded' - hence there's no 'interrupted stack' to print a backtrace of. You should be able to see all (including currently running) task's backtraces in SysRq-T output. are you trying to use it to debug a particular bug? Ingo - 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/