From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757351Ab0GNSVZ (ORCPT ); Wed, 14 Jul 2010 14:21:25 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:57485 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754886Ab0GNSVW (ORCPT ); Wed, 14 Jul 2010 14:21:22 -0400 X-Authority-Analysis: v=1.1 cv=FmZLatDjtfD3C7oE6GdrxaCbsxiNBR9ZXBX9JZchN1o= c=1 sm=0 a=0EwOLGvg4BAA:10 a=ood2b7iyd8MA:10 a=IkcTkHD0fZMA:10 a=gMqfjgEr1zLu/65IO0LwxA==:17 a=47zC1ddeBiJHrmnMto8A:9 a=BzU03m1SYNvabAPv13GgVyFC-3gA:4 a=QEXdDO2ut3YA:10 a=gMqfjgEr1zLu/65IO0LwxA==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.89.75 Subject: Re: [tip:x86/irq] x86: Always use irq stacks From: Steven Rostedt To: Christoph Hellwig Cc: Thomas Gleixner , Ingo Molnar , mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org In-Reply-To: <20100714154746.GA2074@lst.de> References: <20100628121554.GA6605@lst.de> <20100630074434.GA25509@elte.hu> <20100630075212.GA24658@lst.de> <20100630075818.GB25509@elte.hu> <20100630080453.GA14371@elte.hu> <20100708204251.GA13569@elte.hu> <20100708205302.GA23961@lst.de> <20100714151215.GA31825@lst.de> <20100714154746.GA2074@lst.de> Content-Type: text/plain; charset="UTF-8" Date: Wed, 14 Jul 2010 14:21:12 -0400 Message-ID: <1279131672.4190.18.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 (2.28.3-1.fc12) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2010-07-14 at 17:47 +0200, Christoph Hellwig wrote: > On Wed, Jul 14, 2010 at 05:27:01PM +0200, Thomas Gleixner wrote: > > On Wed, 14 Jul 2010, Christoph Hellwig wrote: > > > > > Turns out this wasn't a regression introduced by a commit, but it > > > happens when CONFIG_FUNCTION_GRAPH_TRACER is enabled. From a quick > > > look I have no idea why these would interact badly, especially as > > > CONFIG_FUNCTION_GRAPH_TRACER works fine with irq stacks if the > > > CONFIG_4KSTACKS options is set. > > > > So you're saying, that the problem appears when > > CONFIG_FUNCTION_GRAPH_TRACER is enabled w/o being used and that it > > exists prior to your patches with irq stacks and 8k stack size, but > > works with 4k stacks. That's definitely more than odd. > > No, the problem does not show up with 8k stack size without irqstacks, > and does not show up with 4k stacks with irq stacks, but does show up > with 8k stacks with irqstacks as long as CONFIG_FUNCTION_GRAPH_TRACER is > enabled. Just disabling it in Ingo's example config makes it work, > and enabling it in my usual test configs makes the boot fail with > similar messages to the one Ingo sees. I'm currently at OLS, but I can take a look at this in more detail when I get back on Monday. -- Steve