From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id C51BB68630 for ; Mon, 31 Oct 2005 13:19:26 +1100 (EST) From: Benjamin Herrenschmidt To: Ingmar In-Reply-To: <20051031002926.M71008@quicknet.nl> References: <1130645036.29054.229.camel@gaston> <20051031002926.M71008@quicknet.nl> Content-Type: text/plain; charset=utf-8 Date: Mon, 31 Oct 2005 13:17:58 +1100 Message-Id: <1130725079.29054.320.camel@gaston> Mime-Version: 1.0 Cc: linuxppc-dev list Subject: Re: exception vectors List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, 2005-10-31 at 01:35 +0100, Ingmar wrote: > Hi all, > > I am trying to overwrite the exception vector space of an ibook G4 :). > > I have set up (for every exception) a small piece of code, that's a prefix of a > handler to be called. My problem is, that writing the “small” chunks of code to > the exception vector space gives no problem(so it seams) but writing all the > pieces of code as one chunk gives a exception [dsi, dsisr 0x42000000], this > indicates a store problem. > > I have tried different modes of copying, mmu on/off, also chanced the WING bit, > switched the exception prefix on. > > I don't believe putting the exception vectors to there “place” one by one is the > right way, in the Linux kernel the kernel get relocated and the code comes into > place. I have taken this as an example, unfortunately to to result :(.. > > - Am I overlooking something? > - Is the a “standard way” to overwrite the exception vector space of a powerpc? Well, you typically do this with the MMU disabled and making sure you don't take an exception while copying over them... Ben.