From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 4/6] kvm-userland.git mmu notifier compat Date: Tue, 29 Jul 2008 16:30:42 +0300 Message-ID: <488F1B82.2080405@qumranet.com> References: <20080725142452.GA8217@duo.random> <20080725142639.GB8217@duo.random> <20080725143203.GC8217@duo.random> <20080725143834.GD8217@duo.random> <488F11C4.5050109@qumranet.com> <20080729130335.GM11494@duo.random> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , kvm@vger.kernel.org To: Andrea Arcangeli Return-path: Received: from il.qumranet.com ([212.179.150.194]:23501 "EHLO il.qumranet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753116AbYG2Nao (ORCPT ); Tue, 29 Jul 2008 09:30:44 -0400 In-Reply-To: <20080729130335.GM11494@duo.random> Sender: kvm-owner@vger.kernel.org List-ID: Andrea Arcangeli wrote: > On Tue, Jul 29, 2008 at 03:49:08PM +0300, Avi Kivity wrote: > >> Applied; thanks. I think page pinning can be worked around by pinning all >> pages on memslot registration (and unpinning on memslot removal); this will >> slow down virtual machine startup, but is at least simple. >> > > This has the benefit that will also fix the tlb issues, but if we go > this way if a sles/rhel user takes the next kvm release, all ram will > be pinned and it won't swap anything for him, like with my patch that > added VM_LOCKED. Said that swap wasn't a reliable feature before so > nobody should have depended on that. > A 64-bit guest would pin all pages anyway as soon as it touched them the first time, through the direct map. > If we really go this memslot-wide-pinning way I could submit to rhel > and sles a mmu notifier backport so the rhel/sles users won't have to > wait to get their kernel upgraded to 2.6.27 to get full kvm-paging. > I really doubt they would take it; Red Hat will want to point people at ovirt and Novel at Xen. It's not a simple patch. -- error compiling committee.c: too many arguments to function