From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754488Ab0JTRFd (ORCPT ); Wed, 20 Oct 2010 13:05:33 -0400 Received: from claw.goop.org ([74.207.240.146]:51975 "EHLO claw.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753036Ab0JTRFc (ORCPT ); Wed, 20 Oct 2010 13:05:32 -0400 Message-ID: <4CBF2158.7060600@goop.org> Date: Wed, 20 Oct 2010 10:05:28 -0700 From: Jeremy Fitzhardinge User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.9) Gecko/20100921 Fedora/3.1.4-1.fc13 Lightning/1.0b3pre Thunderbird/3.1.4 MIME-Version: 1.0 To: Stefano Stabellini CC: Konrad Rzeszutek Wilk , Jeremy Fitzhardinge , "linux-kernel@vger.kernel.org" , Ian Campbell , "xen-devel@lists.xensource.com" Subject: Re: [Xen-devel] Re: [PATCH v3 08/10] xen: use host E820 map for dom0 References: <1286901770-8612-8-git-send-email-Stefano.Stabellini@eu.citrix.com> <20101018155412.GD27373@dumpdata.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/19/2010 03:49 AM, Stefano Stabellini wrote: >>> - e820_add_region(0, PFN_PHYS((u64)max_pfn), E820_RAM); >>> - >>> + for (i = 0; i < memmap.nr_entries; i++) { >>> + unsigned long long end = map[i].addr + map[i].size; >>> + if (map[i].type == E820_RAM) { >>> + if (map[i].addr > mem_end) >>> + continue; >> Would it make sense to print out a message saying something to the >> effect of: "You need to increase the CONFIG_XEN_MAX_DOMAIN_MEMORY value to >> take advantage of the extra %d gobs of memory!\n", map[i].size >> >> Or will this be unneccessary with the later changes that Jeremy has >> for the balloon work? >> > I think it still makes a lot of sense to print that message because > ballooning might be disabled. CONFIG_XEN_MAX_DOMAIN_MEMORY scales the max pfn in the p2m table, and it independent of whether ballooning is enabled. The presence or absence of ballooning will only affect whether memory between memory and maxmem can be made available. And it defaults 128G now anyway, so its very unlikely people will hit it by accident. Aside from that, I'm thinking of making ballooning mandatory (perhaps just a config option on the usermode-visible parts), since it seems so core (its mandatory for all the dom0/passthrough stuff anyway). J