From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Vrable Subject: Re: Re: [PATCH] Xen Guest Kexec Date: Mon, 6 Mar 2006 08:04:19 -0800 Message-ID: <20060306160419.GA4015@vrable.net> References: <4406B7FB.6030207@suse.de> <4406D83F.3080709@suse.de> <4b02cf0aeca2fb5aa2cfadb0833ec1cc@cl.cam.ac.uk> <44071EFC.6010307@suse.de> <50867f02a9164fec709c96927802dc45@cl.cam.ac.uk> <440800D9.4030803@suse.de> <12462cbf1e480de2105fa4627592b3bf@cl.cam.ac.uk> <440C43E4.1050204@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <440C43E4.1050204@suse.de> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On Mon, Mar 06, 2006 at 03:15:00PM +0100, Gerd Hoffmann wrote: > * Which events can change the p2m map? I think for domU that is only > ballooning, right? For dom0 additionally the backend drivers (when > mapping foreign pages). Anything else? Networking as well, since network packet reception involves flipping pages between domains. > * Is there some way to rebuild the p2m map from scratch using > hypercalls? As far as I know not completely reliably, since the P2M map is maintained by the guest and Xen is almost entirely uninvolved. You could probably get most of the way there by retrieving a list of pages belonging to the guest (not sure if this can be done from within an unprivileged guest though, or only in Domain-0), then building a reverse map of entries in the M2P table. This will only work if all pages have accurate M2P entries (certainly won't work for domain-0, since it maps foreign pages, but might work for unprivileged domains). --Michael Vrable