From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933490Ab3JORbl (ORCPT ); Tue, 15 Oct 2013 13:31:41 -0400 Received: from terminus.zytor.com ([198.137.202.10]:40240 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932950Ab3JORbk (ORCPT ); Tue, 15 Oct 2013 13:31:40 -0400 Message-ID: <525D7BDE.4070400@zytor.com> Date: Tue, 15 Oct 2013 10:31:10 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130625 Thunderbird/17.0.7 MIME-Version: 1.0 To: Ingo Molnar CC: Yinghai Lu , Tejun Heo , Zhang Yanfei , Zhang Yanfei , Toshi Kani , Ingo Molnar , Andrew Morton , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH part2 v2 0/8] Arrange hotpluggable memory as ZONE_MOVABLE References: <20131014142719.GI4722@htj.dyndns.org> <525C02DC.4050706@gmail.com> <20131014145131.GJ4722@htj.dyndns.org> <525C0866.2010808@gmail.com> <20131014151902.GL4722@htj.dyndns.org> <525C0EFE.2010409@gmail.com> <20131014200437.GA5720@htj.dyndns.org> <525C5727.7000603@zytor.com> <20131015065040.GB24584@gmail.com> In-Reply-To: <20131015065040.GB24584@gmail.com> X-Enigmail-Version: 1.5.2 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 10/14/2013 11:50 PM, Ingo Molnar wrote: > > So if anyone can implement it using huge pages, with a really fast __va() > and __pa() implementation, then it might be possible. But that's a pretty > major surgery on x86. > Well, we already *have* a way to deal with that for Xen (by inserting an otherwise nonexistent logical level.) I'm wondering if those interfaces could be (ab)used for this as well, or if that is functionally equivalent to saying that this should be done in a hypervisor. -hpa