From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: Balloon device in qemu? Date: Mon, 18 Aug 2008 17:00:09 +0300 Message-ID: <48A98069.7020104@qumranet.com> References: <4891B7C2.70800@qumranet.com> <20080801190654.GA24342@dmt.cnet> <4893685B.1080409@us.ibm.com> <20080802130123.GK27246@duo.random> <489655E8.4070401@us.ibm.com> <4896BEBA.4020209@redhat.com> <20080804115649.GF11476@duo.random> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Gerd Hoffmann , Anthony Liguori , Marcelo Tosatti , KVM list To: Andrea Arcangeli Return-path: Received: from il.qumranet.com ([212.179.150.194]:40768 "EHLO il.qumranet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752367AbYHROAK (ORCPT ); Mon, 18 Aug 2008 10:00:10 -0400 In-Reply-To: <20080804115649.GF11476@duo.random> Sender: kvm-owner@vger.kernel.org List-ID: Andrea Arcangeli wrote: > On Mon, Aug 04, 2008 at 10:32:58AM +0200, Gerd Hoffmann wrote: > >> #define KVM_CAP_SYNC_MMU 16 /* Changes to host mmap are reflected in >> guest */ >> >> This one I guess ... >> > > That doesn't currently tell if kvm is using mmu notifiers though, > because it's set unconditionally. If we want to use it to tell if kvm > is using mmu notifiers we've to wrap it around an #ifdef or to use the > awk hack, which is trivial to add. > > I'm more worried about the fact that with Anthony's plan ballooning > will be unusable for a long while on enterprise distros, as it will > take a while before they run on a >=2.6.27 kernel. So I wonder if a > compact layer is worth it. But surely initially we can modify > KVM_CAP_SYNC_MMU to not be set if kernel isn't compiled with > CONFIG_MMU_NOTIFIER=y and we can add the compact layer later if needed. > I added something to hack-module.awk, so KVM_CAP_SYNC_MMU is now reliable. -- error compiling committee.c: too many arguments to function