From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from pentafluge.infradead.org (pentafluge.infradead.org [213.146.154.40]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id 6B5A568175 for ; Wed, 24 Aug 2005 03:00:47 +1000 (EST) From: David Woodhouse To: Marcelo Tosatti In-Reply-To: <20050823025645.GG9667@dmt.cnet> References: <1124317852.24373.13.camel@localhost.localdomain> <8DC63AB4-C547-4023-BE7F-46176BC71535@freescale.com> <20050823025645.GG9667@dmt.cnet> Content-Type: text/plain Date: Tue, 23 Aug 2005 17:43:14 +0100 Message-Id: <1124815395.29448.26.camel@hades.cambridge.redhat.com> Mime-Version: 1.0 Cc: linuxppc-dev list Subject: Re: When are machine checks suppose to be recoverable? List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, 2005-08-22 at 23:56 -0300, Marcelo Tosatti wrote: > "My dual G4 PowerMac crashes sometimes when it probes for the (absent) > serial ports. Theoretically it's supposed to take a machine check and > recover -- but it doesn't always work like that." > > Maybe you just need the proper entry in the exception table for IO > inb/outb? > > Is there a stacktrace, David? No, just a silent death when probing for one of the serial ports; usually not the first. It doesn't seem to even make it into the machine check handler. Adding printks into serial_inb and serial_outb makes it much less likely to happen -- could be something bizarre about alignment of the instructions which cause the machine check, or time elapsed from one machine check to the next. -- dwmw2