Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750916AbbFXEBX (ORCPT ); Wed, 24 Jun 2015 00:01:23 -0400 Received: from mail-vn0-f44.google.com ([209.85.216.44]:41711 "EHLO mail-vn0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750704AbbFXEBN (ORCPT ); Wed, 24 Jun 2015 00:01:13 -0400 MIME-Version: 1.0 In-Reply-To: References: Date: Wed, 24 Jun 2015 09:31:12 +0530 Message-ID: Subject: Re: powerpc,numa: Memory hotplug to memory-less nodes ? From: Bharata B Rao To: linuxppc-dev , "linux-kernel@vger.kernel.org" Cc: Nathan Fontenot , Paul Mackerras , Anton Blanchard Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1066 Lines: 32 So will it be correct to say that memory hotplug to memory-less node isn't supported by PowerPC kernel ? Should I enforce the same in QEMU for PowerKVM ? On Mon, Jun 22, 2015 at 10:18 AM, Bharata B Rao wrote: > Hi, > > While developing memory hotplug support in QEMU for PoweKVM, I > realized that guest kernel has specific checks to prevent hot addition > of memory to a memory-less node. > > I am referring to arch/powerpc/mm/numa.c:hot_add_scn_to_nid() which > has explicit checks to ensure that it returns a nid that has some some > memory (NODE_DATA(nid)->node_spanned_pages) even when user wants to > hotplug to a node that currently has zero memory. > > Is this limitation by design ? > > Regards, > Bharata. > -- > http://raobharata.wordpress.com/ -- http://raobharata.wordpress.com/ -- 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/