From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755947Ab3AJUCa (ORCPT ); Thu, 10 Jan 2013 15:02:30 -0500 Received: from one.firstfloor.org ([213.235.205.2]:37853 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754598Ab3AJUC2 (ORCPT ); Thu, 10 Jan 2013 15:02:28 -0500 Date: Thu, 10 Jan 2013 21:02:23 +0100 From: Andi Kleen To: Davidlohr Bueso Cc: linux-acpi@vger.kernel.org, Andi Kleen , zeus@gnu.org, linux-kernel@vger.kernel.org Subject: Re: srat: harsh hot-pluggable memory check? Message-ID: <20130110200223.GH30577@one.firstfloor.org> References: <1357846907.7523.17.camel@buesod1.americas.hpqcorp.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1357846907.7523.17.camel@buesod1.americas.hpqcorp.net> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > This only mentions that the system supports hot-plugging, and IMHO if the > user decides not to use CONFIG_MEMORY_HOTPLUG, it shouldn't be considered an error. > Therefore would it be ok to drop the check? Or am I missing something? The very strict checks were originally implemented because various early BIOS had largely fictional SRATs, and trusting them blindly caused boot failures or a lot of wasted memory for unnecessary hotplug zones. The wasted memory was mainly a problem with the old memory hotplug implementation that pre-allocated memmaps, that's not a problem anymore. However there may be still some other failure cases. -Andi -- ak@linux.intel.com -- Speaking for myself only.