From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ingo Molnar Subject: Re: [patch] kvm: make cr3 loading more robust Date: Wed, 3 Jan 2007 14:44:17 +0100 Message-ID: <20070103134417.GA22055@elte.hu> References: <20070103021057.GA11316@elte.hu> <459B695C.5090004@qumranet.com> <20070103115911.GA2786@elte.hu> <459B9C5C.9060008@qumranet.com> <20070103122114.GD2786@elte.hu> <459BA194.8070305@qumranet.com> <20070103123253.GA8822@elte.hu> <20070103133714.GA20638@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel Return-path: To: Avi Kivity Content-Disposition: inline In-Reply-To: <20070103133714.GA20638-X9Un+BFzKDI@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org * Ingo Molnar wrote: > instead of a host crash. Note that i chose to put this into the > generic cr3 loading function, so that it covers real-mode too. I think > we can safely ignore a BIOS loading crap into cr3 and after that > loading the right value into it. (if that ever happens we 1) want to > know about it 2) can push the test down into paging_new_cr3()) Agreed? another small detail is that currently KVM_SET_MEMORY_REGION appears to be an add-only interface - it is not possible to 'unregister' RAM from a VM. That keeps things easy for now, but if it's ever implemented then the current cr3 of all vcpus of the VM needs to be validated against the reduced memory slot map. (besides migrating all existing mappings from the removed memory slot to other memory slots and redirecting all in-flight DMA transactions, etc., etc. Which all needs heavy guest-OS awareness as well.) Ingo ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV