From owner-freebsd-xen@FreeBSD.ORG Thu Nov 18 19:10:44 2010 Return-Path: Delivered-To: freebsd-xen@freebsd.org Received: from mx2.freebsd.org (mx2.freebsd.org [IPv6:2001:4f8:fff6::35]) by hub.freebsd.org (Postfix) with ESMTP id E907810656A4 for ; Thu, 18 Nov 2010 19:10:44 +0000 (UTC) (envelope-from cperciva@freebsd.org) Received: from xps.daemonology.net (freefall.freebsd.org [IPv6:2001:4f8:fff6::28]) by mx2.freebsd.org (Postfix) with SMTP id 984E31A499F for ; Thu, 18 Nov 2010 19:10:44 +0000 (UTC) Received: (qmail 6184 invoked from network); 18 Nov 2010 19:10:44 -0000 Received: from unknown (HELO xps.daemonology.net) (127.0.0.1) by localhost with SMTP; 18 Nov 2010 19:10:44 -0000 Message-ID: <4CE57A34.5040105@freebsd.org> Date: Thu, 18 Nov 2010 11:10:44 -0800 From: Colin Percival User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.1.11) Gecko/20100803 Thunderbird/3.0.6 MIME-Version: 1.0 To: "freebsd-xen@freebsd.org" X-Enigmail-Version: 1.0.1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: planning on churning the tree a bit X-BeenThere: freebsd-xen@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion of the freebsd port to xen - implementation and usage List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 18 Nov 2010 19:10:45 -0000 Hi guys, I'm trying to get FreeBSD Xen/PAE working so that FreeBSD can run on a *cough* large cloud computing system, and I'm finding a bunch of breakage. Some obvious breakage: 1. We don't check that the individual hypercalls in a multicall succeeded. 2. In the XEN && PAE case, pmap_release KASSERTs one page mapping too many. 3. In the XEN && PAE case, pmap_pinit calls pmap_qenter on NPGPTD + 1 pages, but pmap_release only calls pmap_qremove on NPGPTD of them. Some brain damage: 1. We have a VM_PAGE_TO_MACH() macro defined, but we're not using it in all the places where it should be used. 2. xen/pmap.c is full of #ifdef XEN, even though the file is not compiled in the !XEN case. I'm going to fix the obvious breakage (and more as I encounter it) and I'd also like to fix the brain damage since that will hopefully make it much easier for me to understand the code. Any objections? -- Colin Percival Security Officer, FreeBSD | freebsd.org | The power to serve Founder / author, Tarsnap | tarsnap.com | Online backups for the truly paranoid