From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ovro.ovro.caltech.edu (ovro.ovro.caltech.edu [192.100.16.2]) by ozlabs.org (Postfix) with ESMTP id 78DDBB6EEF for ; Thu, 9 Sep 2010 12:52:17 +1000 (EST) Date: Wed, 8 Sep 2010 19:52:14 -0700 From: "Ira W. Snyder" To: Benjamin Herrenschmidt Subject: Re: CONFIG_PROVE_LOCKING broken on 83xx (and all of powerpc?) Message-ID: <20100909025214.GA21846@ovro.caltech.edu> References: <20100908232124.GB30291@ovro.caltech.edu> <1283994156.6515.6.camel@pasglop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1283994156.6515.6.camel@pasglop> Cc: peterz@infradead.org, mingo@redhat.com, linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, Sep 09, 2010 at 11:02:36AM +1000, Benjamin Herrenschmidt wrote: > On Wed, 2010-09-08 at 16:21 -0700, Ira W. Snyder wrote: > > > > > > I am happy to provide more information if it will help. I'm not > > especially > > good at working the debugger. I can't get it to stop at machine_init() > > and let > > me step through the code. > > > > I tried this feature when it first became available on powerpc, and it > > did not work then. At that time, I didn't have the resources to > > investigate further. I don't think a git bisect will help in this > > case. > > That's a concern... lockdep_init() is expected to only perform static > initializations... > Yes, I looked over the function, and I don't understand where it goes wrong. > Any chance you can stick a data breakpoint early on to catch when the > corruption happens ? > I will attempt to get the debugger to stop at start_kernel. I'm having trouble driving the JTAG debugger (a BDI2000). I have used Denx's guide [1] in the past, but the section on debugging the kernel itself is now missing. [1] http://www.denx.de/wiki/view/DULG/DebuggingLinuxKernel I'll keep trying. Thanks for the reply, Ira