From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from pythia.bakeyournoodle.com (pythia.bakeyournoodle.com [203.82.209.197]) by ozlabs.org (Postfix) with ESMTP id D8289DDE26 for ; Fri, 4 Jul 2008 13:14:50 +1000 (EST) Date: Fri, 4 Jul 2008 13:14:49 +1000 From: Tony Breeds To: Olaf Hering Subject: Re: [PATCH v2] Change the default link address for pSeries zImage kernels. Message-ID: <20080704031449.GW20457@bakeyournoodle.com> References: <1a551391a3c4925271cc86cb2e957aaccb0b599c.1214208801.git.tony@bakeyournoodle.com> <4ca08ab3df251d90440c962ef15ead1a72d75f05.1214276944.git.tony@bakeyournoodle.com> <20080702150432.GA5910@aepfle.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 In-Reply-To: <20080702150432.GA5910@aepfle.de> Cc: linuxppc-dev@ozlabs.org, Paul Mackerras List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, Jul 02, 2008 at 05:04:32PM +0200, Olaf Hering wrote: > Setting real-base to what? 32Mb, or any other value big enough to allow the tftp to fit in ${real-base} - ${load-base}. I admitt it's far from ideal. > What currently happens with a large boot file is: > Firmware loads the zImage at load-base, finds that the ELF file is too > large to fit into the memory window and stops. > > With your patch, firmware loads 12566528 bytes, and starts the zImage. > The result is a truncated file, the initrd will be corrupted, kernel > panic in populate_rootfs(). Okay that's not the behaviour I see here on the POWER4 machines, they grab the firt n bytes (probabbly 12566528), and then abort with a message about image being too large and it cannot be split. (something akin to https://bugzilla.novell.com/show_bug.cgi?id=350212 ) > The only system where firmware relocates itself from 12MB to 32MB is a > p640 with firmware version NAN04194. > All other systems seem to ignore the NOTE section, real-base remains at > 0xc00000 Add I thought /all/ POWER4 systems were unable to relocate OF (regardless of whether the request is from the NOTE or from set-env real-base). > So I do not think your patch is a real improvement, > clear error vs. silent corruption. > > Do you happen to know how to automate the changing the value of > real-base? The addnote change has appearently no effect on recent > systems. It's there for POWER5 and on. I was sure that no POWER4 machines could be reloacted, but you say that your p640 can. Yours Tony linux.conf.au http://www.marchsouth.org/ Jan 19 - 24 2009 The Australian Linux Technical Conference!