Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757966Ab1F2VYp (ORCPT ); Wed, 29 Jun 2011 17:24:45 -0400 Received: from mail-vx0-f174.google.com ([209.85.220.174]:52185 "EHLO mail-vx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752263Ab1F2VYn (ORCPT ); Wed, 29 Jun 2011 17:24:43 -0400 MIME-Version: 1.0 In-Reply-To: References: <532cc290-4b9c-4eb2-91d4-aa66c01bb3a0@glegroupsg2000goo.googlegroups.com> <20110629080827.GA975@phantom.vanrein.org> Date: Wed, 29 Jun 2011 14:24:41 -0700 X-Google-Sender-Auth: 7zJLqAvrzV3j-Jv4nSjGZ8w26Go Message-ID: Subject: Re: [PATCH v2 0/3] support for broken memory modules (BadRAM) From: Tony Luck To: Craig Bergstrom Cc: linux-kernel@vger.kernel.org, fa.linux.kernel@googlegroups.com, Rick van Rein , "H. Peter Anvin" , Stefan Assmann , "linux-mm@kvack.org" , "akpm@linux-foundation.org" , Andi Kleen , "mingo@elte.hu" , "rdunlap@xenotime.net" , Nancy Yuen , Michael Ditto Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1056 Lines: 25 One extra consideration for this whole proposal ... Is the "physical address" a stable enough representation of the location of the faulty memory cells? On high end systems I can see a number of ways where the mapping from cells to physical address may change across reboot: 1) System support redundant memory (rank sparing or mirroring) 2) BIOS self test removes some memory from use 3) A multi-node system elects a different node to be boot-meister, which results in reshuffling of the address map. If any of these can happen: then it doesn't matter whether we have a list of addresses, or a pattern that expands to a list of addresses. We'll still mark some innocent memory as bad, and allow some known bad memory to be used - because our "addresses" no longer correspond to the bad memory cells. -Tony -- 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/