Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760599AbYFTVog (ORCPT ); Fri, 20 Jun 2008 17:44:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753934AbYFTVo0 (ORCPT ); Fri, 20 Jun 2008 17:44:26 -0400 Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:40128 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752864AbYFTVoZ (ORCPT ); Fri, 20 Jun 2008 17:44:25 -0400 Date: Fri, 20 Jun 2008 14:44:24 -0700 (PDT) Message-Id: <20080620.144424.168785883.davem@davemloft.net> To: mpatocka@redhat.com Cc: sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org, agk@redhat.com Subject: Re: stack overflow on Sparc64 From: David Miller In-Reply-To: References: <20080620.142034.30884440.davem@davemloft.net> X-Mailer: Mew version 5.2 on Emacs 22.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1471 Lines: 39 From: Mikulas Patocka Date: Fri, 20 Jun 2008 17:25:26 -0400 (EDT) > On Fri, 20 Jun 2008, David Miller wrote: > > > From: Mikulas Patocka > > Date: Fri, 20 Jun 2008 17:14:41 -0400 (EDT) > > > > It means i386 and every other platform potentially has the same exact > > problem. > > > > What point wrt. sparc64 are you trying to make here? :-) > > The difference is that i386 takes minimum 4 bytes per stack frame and > sparc64 192 bytes per stack frame. So this problem will kill sparc64 > sooner. > > But yes, it is general problem and should be solved in arch-independent > code. I agree on both counts. Although I'm curious what the average stack frame sizes look like on x86_64 and i386, and also how this area appears on powerpc. One mitigating factor on sparc64 is that typically when there are lots of devices with interrupts there are also lots of cpus, and we evenly distribute the IRQ targetting amongst the available cpus on sparc64. This is probably why, in practice, these problems tend to not surface often. In any event, with the work you've accomplished and my implementation of IRQ stacks for sparc64 we should be able to get things in much better shape. -- 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/