From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 4779 invoked by alias); 22 Nov 2005 01:25:01 -0000 Received: (qmail 4743 invoked by uid 22791); 22 Nov 2005 01:25:01 -0000 X-Spam-Status: No, hits=-2.5 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from gateway.sf.frob.com (HELO gateway.sf.frob.com) (64.81.54.130) by sourceware.org (qpsmtpd/0.31) with ESMTP; Tue, 22 Nov 2005 01:25:00 +0000 Received: from magilla.sf.frob.com (magilla.sf.frob.com [198.49.250.228]) by gateway.sf.frob.com (Postfix) with ESMTP id BF635357B; Mon, 21 Nov 2005 17:24:57 -0800 (PST) Received: by magilla.sf.frob.com (Postfix, from userid 5281) id 76E061809B9; Mon, 21 Nov 2005 17:24:57 -0800 (PST) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Roland McGrath To: "Stone, Joshua I" Cc: Subject: Re: double fault In-Reply-To: Stone, Joshua I's message of Monday, 21 November 2005 17:12:14 -0800 X-Antipastobozoticataclysm: When George Bush projectile vomits antipasto on the Japanese. Message-Id: <20051122012457.76E061809B9@magilla.sf.frob.com> Date: Tue, 22 Nov 2005 01:25:00 -0000 X-IsSubscribed: yes Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2005-q4/txt/msg00226.txt.bz2 The stack overflow notion sounds plausible. To investigate that angle, one thing to try comes to mind off hand. In each probe that might be hitting, stick some %{ ... %} code to do a "stack getting small" check. It can do something like: unsigned left = (unsigned)regs & 0xfff; if (left < 256) panic("stack getting close"); That might manage to print out a full oops with backtrace details that show the cascade of page fault frames or whatever the situation actually is. Thanks, Roland