Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751304AbWAEOaq (ORCPT ); Thu, 5 Jan 2006 09:30:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751323AbWAEOaq (ORCPT ); Thu, 5 Jan 2006 09:30:46 -0500 Received: from gateway-1237.mvista.com ([12.44.186.158]:28405 "EHLO hermes.mvista.com") by vger.kernel.org with ESMTP id S1751304AbWAEOap (ORCPT ); Thu, 5 Jan 2006 09:30:45 -0500 Subject: RE: Latency traces I cannot interpret (sa1100, 2.6.15-rc7-rt1) From: Daniel Walker To: kus Kusche Klaus Cc: Ingo Molnar , Lee Revell , linux-kernel In-Reply-To: References: Content-Type: text/plain Date: Thu, 05 Jan 2006 06:30:42 -0800 Message-Id: <1136471443.31011.1.camel@localhost.localdomain> 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: 1092 Lines: 32 On Wed, 2006-01-04 at 10:28 +0100, kus Kusche Klaus wrote: > > From: Daniel Walker > > Ok, yet another patch. This one uses the correct lowlevel calls, and I > > fixed the call ordering. > > Hmm, I have no deep knowledge of ARM assembler programming, > but your patch branches to a C subroutine without setting up a > return address in the lr register. > > Hence, the return in trace_irqs_... jumps to god-knows-where, > but not back to the next instruction. > > As a wild guess, I replaced the "b trace_irqs_..." with > "bl trace_irqs_...". Ok . > With this change, the kernel boots fine, but the system seems to go > into an infinite loop as soon as the first usermode processes start. > Most likely, my change messes up the lr register of some surrounding > context. That's odd. Do you have an OOPS, or is it just a silent hang? 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/