Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262443AbUCaUSt (ORCPT ); Wed, 31 Mar 2004 15:18:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262448AbUCaUSt (ORCPT ); Wed, 31 Mar 2004 15:18:49 -0500 Received: from chaos.analogic.com ([204.178.40.224]:3973 "EHLO chaos.analogic.com") by vger.kernel.org with ESMTP id S262443AbUCaUSo (ORCPT ); Wed, 31 Mar 2004 15:18:44 -0500 Date: Wed, 31 Mar 2004 15:13:31 -0500 (EST) From: "Richard B. Johnson" X-X-Sender: root@chaos Reply-To: root@chaos.analogic.com To: davidm@hpl.hp.com cc: Alex Williamson , Denis Vlasenko , ulrich.windl@rz.uni-regensburg.de, linux-kernel Subject: Re: 2.4.21 on Itanium2: floating-point assist fault at ip 400000000062ada1, isr 0000020000000008 In-Reply-To: <16491.6076.504437.267920@napali.hpl.hp.com> Message-ID: References: <406AE0D5.10359.1930261@localhost> <200403311900.17293.vda@port.imtp.ilyichevsk.odessa.ua> <16491.2184.253165.545651@napali.hpl.hp.com> <1080757433.2326.32.camel@patsy.fc.hp.com> <16491.6076.504437.267920@napali.hpl.hp.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1428 Lines: 40 On Wed, 31 Mar 2004, David Mosberger wrote: > >>>>> On Wed, 31 Mar 2004 13:53:13 -0500 (EST), "Richard B. Johnson" said: > > Richard> The power-on or hardware-reset default for the ix86 FPU > Richard> is to attempt to handle div 0 errors transparently. > > I must be missing something. So far I haven't seen anything that > would suggest the FPSWA faults were due to infinities. I'd guess that > it's much more likely that they're due to denormals. > > --david ftp://download.intel.com/design/Itanium/Downloads/24541401.pfd "Itanium Processor Floating-point Software Assistance and Floating-Point Exception Handling" Any FPU fault gets trapped to this code. Nans, Denormals, Overflow, Inexact, etc., everything.... The reading of 2.2 may not be clear, but further reading will show that anything that didn't go according to plan gets trapped to the "Software Assistance" Handler. Writing a message about the trap to a log-file is a BUG! The handler should just do whatever it's supposed to do! Cheers, Dick Johnson Penguin : Linux version 2.4.24 on an i686 machine (797.90 BogoMips). Note 96.31% of all statistics are fiction. - 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/