From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: [discuss] Re: [RFC:PATCH(003/003)] Memory add to onlined node. (ver. 2) (For x86_64) Date: Thu, 9 Feb 2006 11:41:43 +0100 Message-ID: <200602091141.44456.ak@suse.de> References: <20060209153803.6CF4.Y-GOTO@jp.fujitsu.com> <20060209164036.6CFC.Y-GOTO@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from ns2.suse.de ([195.135.220.15]:47291 "EHLO mx2.suse.de") by vger.kernel.org with ESMTP id S1030627AbWBIKmL (ORCPT ); Thu, 9 Feb 2006 05:42:11 -0500 In-Reply-To: <20060209164036.6CFC.Y-GOTO@jp.fujitsu.com> Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: discuss@x86-64.org Cc: Yasunori Goto , "Tolentino, Matthew E" , "Brown, Len" , naveen.b.s@intel.com, Bjorn Helgaas , Linux Kernel ML , ACPI-ML , Linux Hotplug Memory Support On Thursday 09 February 2006 10:50, Yasunori Goto wrote: > Current code adds memory to ZONE_NORMAL like this. > But, ZONE_DMA32 is available on 2.6.15. So, I'm afraid there are > 2 types trouble. > > a) When new memory is added to < 4GB, this should be added to > Zone_DMA32. > Are there any real machine which allow to add memory under > 4GB? x86-64 machines usually use a continuous memory map because Windows gets unhappy with too big memory holes (and even Linux is not completely troublefree for UP install kernels) And for a small system this implies memory < 4GB. > b) If machine boots up with under 4GB memory, and new memory > is added to over 4GB, then kernel might panic due to Zone Normal's > initialization is imcomplete. > > Q2) > Are there any real machine which can add memory with NUMA feature? There are and will be. -Andi